LM22670_17 TI1 | Alldatasheet
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Sample & Buy T echnical Documents Tools & Software Support & Community LM22670,LM22670-Q1 SNVS584P –SEPTEMBER 2008–REVISED NOVEMBER 2014 LM22670/-Q142-V,3-ASIMPLESWITCHER®,Step-DownVoltageRegulator WithFeatures
1 Features 3 Description
The LM22670 switching regulator provides all of the 1• Wide Input Voltage Range: 4.5 V to 42 V functions necessary to implement an efficient high-• Internally Compensated Voltage Mode Control voltage step-down (buck) regulator using a minimum
- Stable With Low ESR Ceramic Capacitors of external components. This easy-to-use regulator incorporates a 42-V N-channel MOSFET switch that• 120-mΩ N-channel MOSFET PFM Package can provide up to 3 A of load current. Excellent line• 100-mΩ N-channel MOSFET SO PowerPAD™ -8 and load regulation along with high efficiency (> 90%)Package are featured. Voltage mode control offers short
- Output Voltage Options: minimum on-time, allowing the widest ratio between -ADJ (Outputs as Low as 1.285 V) input and output voltages. Internal loop compensation -5.0 (Output Fixed to 5 V) means that the user is free from the tedious task of calculating the loop compensation components. Fixed• ±1.5% Feedback Reference Accuracy 5-V output and adjustable output voltage options are• 500-kHz Default Switching Frequency available. The default switching frequency is set at
- Adjustable Switching Frequency and 500 kHz, thus allowing for small external components Synchronization and good transient response. In addition, the frequency can be adjusted over a range of 200 kHz• –40°C to 125°C Operating Junction Temperature to 1 MHz with a single external resistor. The internalRange oscillator can be synchronized to a system clock or to• Precision Enable Pin the oscillator of another regulator. A precision enable
- Integrated Boot-Strap Diode input allows simplification of regulator control and system power sequencing. In shutdown mode the• Integrated Soft-Start regulator draws only 25 µA (typical). Built in soft-start• Fully WEBENCH® Enabled (500 µs, typical) saves external components. The
- LM22670-Q1 is an Automotive-Grade Product LM22670 device also has built-in thermal shutdown, that is AEC-Q100 Grade 1 Qualified (–40°C to and current limiting to protect against accidental +125°C Operating Junction Temperature) overloads. The LM22670 device is a member of Texas2 Applications Instruments' SIMPLE SWITCHER® family. The SIMPLE SWITCHER® concept provides for an easy-• Industrial Control to-use complete design using a minimum number of• Telecom and Datacom Systems external components and the TI WEBENCH design• Embedded Systems tool. TI's WEBENCH tool includes features such as
- Conversions from Standard 24-V, 12-V and 5-V external component calculation, electrical simulation, thermal simulation, and Build-It boards for easyInput Rails design-in. Simplified Application Schematic Device Information(1) PART NUMBER PACKAGE BODY SIZE (NOM) HSOP (8) 4.89 mm x 3.90 mmLM22670 LM22670-Q1 TO-263 (7) 10.16 mm x 9.85 mm (1) For all available packages, see the orderable addendum at the end of the data sheet. An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications, intellectual property matters and other important disclaimers. PRODUCTION DATA.
LM22670,LM22670-Q1 SNVS584P –SEPTEMBER 2008–REVISED NOVEMBER 2014 www.ti.com Table of Contents
4 Revision History
Changes from Revision O (March 2013) to Revision P Page
- Added Pin Configuration and Functions section, Handling Rating table, Thermal Information table, Feature Description section, Device Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical,
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Product Folder Links: LM22670 LM22670-Q1
5 RT/SYNC
3 BOOT
2 VIN
4 GND
7 VIN
6 GND
LM22670,LM22670-Q1 www.ti.com SNVS584P –SEPTEMBER 2008–REVISED NOVEMBER 2014
5 Pin Configuration and Functions
SO TYPE DESCRIPTION APPLICATION INFORMATIONPFMNAME PowerPAD-8 PackagePackage BOOT 1 3 I Bootstrap input Provides the gate voltage for the high side NFET. Pin is not electrically connected inside the chip. PinNC 2 — — Not Connected does function as thermal conductor. Used to control oscillator mode of regulator. SeeOscillator mode controlRT/SYNC 3 5 I Switching Frequency Adjustment and Synchronizationinput and Self-Synchronization of data sheet. FB 4 6 I Feedback input Feedback input to regulator. Used to control regulator start-up and shut-down. SeeEN 5 7 I Enable input Precision Enable and UVLO of data sheet. Ground input to GND 6 4 — regulator; System ground pin. system common VIN 7 2 I Input voltage Supply input to the regulator. SW 8 1 O Switch output Switching output of regulator. Connect to ground. Provides thermal connection toEP EP EP — Exposed Pad PCB. See Application and Implementation. Copyright © 2008–2014, Texas Instruments Incorporated Submit Documentation Feedback 3 Product Folder Links: LM22670 LM22670-Q1
LM22670,LM22670-Q1 SNVS584P –SEPTEMBER 2008–REVISED NOVEMBER 2014 www.ti.com
6 Specifications
6.1 Absolute Maximum Ratings(1)(2)
EN Pin Voltage –0.5 6 RT/SYNC Pin Voltage –0.5 7 V SW to GND(3) –5 VIN BOOT Pin Voltage VSW + 7 FB Pin Voltage –0.5 7 Power Dissipation Internally Limited Junction Temperature 150 °C For soldering specifications, refer to Application Report Absolute Maximum Ratings for Soldering (SNOA549). (1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur, including inoperability and degradation of device reliability and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or other conditions beyond those indicated in the Recommended Operating Conditions is not implied. The Recommended Operating Conditions indicate conditions at which the device is functional and should not be operated beyond such conditions. (2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/Distributors for availability and specifications. (3) The absolute maximum specification of the ‘SW to GND’applies to dc voltage. An extended negative voltage limit of –10 V applies to a pulse of up to 50 ns.
6.2 Handling Ratings: LM22670
Tstg Storage temperature range –65 150 °C Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, allV(ESD) Electrostatic discharge –2 2 kVpins(1) (1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
6.3 Handling Ratings: LM22670-Q1
Tstg Storage temperature range –65 150 °C V(ESD) Electrostatic discharge Human body model (HBM), per AEC Q100-002(1) –2 2 kV (1) AEC Q100-002 indicates HBM stressing is done in accordance with the ANSI/ESDA/JEDEC JS-001 specification.
6.4 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted) MIN MAX UNIT VIN Supply Voltage 4.5 42 V Junction Temperature Range –40 125 °C
6.5 Thermal Information
LM22670, LM22670-Q1 THERMAL METRIC(1)(2)(3) UNITDDA NDR
8 PINS 7 PINS
RθJA Junction-to-ambient thermal resistance 60 22 °C/W (1) For more information about traditional and new thermal metrics, see the application report IC Package Thermal Metrics (SPRA953). (2) The value of RθJA for the PFM package of 22°C/W is valid if package is mounted to 1 square inch of copper. The RθJA value can range from 20 to 30 °C/W depending on the amount of PCB copper dedicated to heat transfer. See application note AN-1797 TO-263 THIN (3) The value of RθJA for the SO Power PAD-8 exposed pad package of 60°C/W is valid if package is mounted to 1 square inch of copper. The RθJA value can range from 42 to 115°C/W depending on the amount of PCB copper dedicated to heat transfer.
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Product Folder Links: LM22670 LM22670-Q1
LM22670,LM22670-Q1 www.ti.com SNVS584P –SEPTEMBER 2008–REVISED NOVEMBER 2014
6.6 Electrical Characteristics
Typical values represent the most likely parametric norm at TA = TJ = 25°C, and are provided for reference purposes only. Unless otherwise specified: VIN = 12 V. PARAMETER TEST CONDITIONS MIN(1) TYP(2) MAX(1) UNIT LM22670-5.0 VIN = 8 V to 42 V 4.925 5.0 5.075 VFB Feedback Voltage V VIN = 8 V to 42 V, –40°C ≤ TJ ≤ 125°C 4.9 5.1 LM22670-ADJ VIN = 4.7 V to 42 V 1.266 1.285 1.304 VFB Feedback Voltage V VIN = 4.7 V to 42 V, –40°C ≤ TJ ≤ 125°C 1.259 1.311 ALL OUTPUT VOLTAGE VERSIONS VFB = 5 V 3.4 IQ Quiescent Current mA VFB = 5 V, –40°C ≤ TJ ≤ 125°C 6 ISTDBY Standby Quiescent Current EN Pin = 0 V 25 40 µA 3.4 4.2 5.3 ICL Current Limit A VIN = 42 V, EN Pin = 0 V, VSW = 0 V 0.2 2 µA IL Output Leakage Current VSW = –1 V 0.1 3 µA RDS(ON) Switch On-Resistance Ω SO PowerPAD-8 Package 0.10 0.16 SO PowerPAD-8 Package, –40°C ≤ TJ ≤ 125°C 0.20 500 fO Oscillator Frequency kHz –40°C ≤ TJ ≤ 125°C 400 600 200 TOFFMIN Minimum Off-time ns –40°C ≤ TJ ≤ 125°C 100 300 TONMIN Minimum On-time 100 ns IBIAS Feedback Bias Current VFB = 1.3 V (ADJ Version Only) 230 nA Falling 1.6 VEN Enable Threshold Voltage V Falling, –40°C ≤ TJ ≤ 125°C 1.3 1.9 VENHYST Enable Voltage Hysteresis 0.6 V IEN Enable Input Current EN Input = 0 V 6 µA Maximum SynchronizationFSYNC VSYNC = 3.5 V, 50% duty-cycle 1 MHzFrequency Synchronization ThresholdVSYNC 1.75 VVoltage TSD Thermal Shutdown Threshold 150 °C (1) MIN and MAX limits are 100% production tested at 25°C. Limits over the operating temperature range are ensured through correlation using Statistical Quality Control (SQC) methods. Limits are used to calculate TI's Average Outgoing Quality Level (AOQL). (2) Typical values represent most likely parametric norms at the conditions specified and are not ensured. Copyright © 2008–2014, Texas Instruments Incorporated Submit Documentation Feedback 5 Product Folder Links: LM22670 LM22670-Q1
6.7 Typical Characteristics
Figure 2. Normalized Switching Frequency vs TemperatureFigure 1. Efficiency vs IOUT and VIN, VOUT = 3.3 V Figure 3. Current Limit vs Temperature Figure 4. Normalized RDS(ON) vs Temperature Figure 5. Feedback Bias Current vs Temperature Figure 6. Normalized Enable Threshold Voltage vs
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1.285V Soft-Start INT REG, EN,UVLO GNDRT/SYNC SW BOOT VIN EN FB VIN VOUT Error Amp. PWM Cmp. Vcc ILimit LM22670,LM22670-Q1 SNVS584P –SEPTEMBER 2008–REVISED NOVEMBER 2014 www.ti.com
7 Detailed Description
7.1 Overview
The LM22670 device incorporates a voltage mode constant frequency PWM architecture. In addition, input voltage feedforward is used to stabilize the loop gain against variations in input voltage. This allows the loop compensation to be optimized for transient performance. The power MOSFET, in conjunction with the diode, produce a rectangular waveform at the switch pin, that swings from about zero volts to VIN. The inductor and output capacitor average this waveform to become the regulator output voltage. By adjusting the duty cycle of this waveform, the output voltage can be controlled. The error amplifier compares the output voltage with the internal reference and adjusts the duty cycle to regulate the output at the desired value. The internal loop compensation of the -ADJ option is optimized for outputs of 5 V and below. If an output voltage of 5 V or greater is required, the -5.0 option can be used with an external voltage divider. The minimum output voltage is equal to the reference voltage, that is, 1.285 V (typ).
7.2 Functional Block Diagram
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Product Folder Links: LM22670 LM22670-Q1
7.3 Feature Description
7.3.1 Precision Enable and UVLO
exceed the 6 V absolute maximum specification for this pin. Voff is the input voltage where the regulator shuts off. Von is the voltage where the regulator turns on. the absolute maximum ratings on this pin. Figure 11. External UVLO Connections
7.3.2 Soft-Start
not be changed. Soft-start is reset any time the part is shut down or a thermal overload event occurs.
7.3.3 Switching Frequency Adjustment and Synchronization
voltage at 0.8 V; therefore, the resulting current sets the mode to allow the resistor to control the clock frequency. allow external synchronization. The mode is latched until either the EN or the input supply is cycled. compensation restricts the range of these components. Electrical Characteristics table. is lost during normal operation, the regulator will revert to the 500 kHz (typ) internal clock. Figure 12. Switching Frequency vs RT/SYNC Resistor
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7.3.4 Self-Synchronization
Figure 13. Self-Synchronization Set up
7.3.5 Boot-Strap Supply
be provided by the output voltage divider, if used.
7.3.6 Internal Loop Compensation
external power stage components. 5 V or greater is needed, the -5.0 option with an external resistor divider can be used. spreadsheet can also be downloaded from the online product folder. product of inductance and output capacitance should conform to Equation 3.
Alternatively, this pole should be placed between 1.5 kHz and 15 kHz and is given by Equation 4. components (see Application and Implementation for more details). Figure 14. Compensator Gain design practice dictates that load and line transient testing should be done to verify the stability of the application. measurement with only an oscilloscope and function generator.
7.4 Device Functional Modes
7.4.1 Shutdown Mode
shutdown mode. In this state, the current drain from the input supply is 25 µA (typ) at an input voltage of 12 V. properly bias the internal circuitry. The rising threshold is 4.3 V (typ) while the falling threshold is 3.9 V (typ).
7.4.2 Active Mode
resistor of 470 kΩ will limit the current to a safe value for input voltages as high 42 V.
7.4.3 Current Limit
L is the value of the power inductor.
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LM22670,LM22670-Q1 www.ti.com SNVS584P –SEPTEMBER 2008–REVISED NOVEMBER 2014 Device Functional Modes (continued) When the LM22670 enters current limit, the output voltage will drop and the peak inductor current will be fixed at ICL at the end of each cycle. The switching frequency will remain constant while the duty cycle drops. The load current will not remain constant, but will depend on the severity of the overload and the output voltage. For very severe overloads ("short-circuit"), the regulator changes to a low frequency current foldback mode of operation. The frequency foldback is about 1/5 of the nominal switching frequency. This will occur when the current limit trips before the minimum on-time has elapsed. This mode of operation is used to prevent inductor current "run-away", and is associated with very low output voltages when in overload. Equation 6 can be used to determine what level of output voltage will cause the part to change to low frequency current foldback. (6) Where: Fsw is the normal switching frequency. Vin is the maximum for the application. If the overload drives the output voltage to less than or equal to Vx, the part will enter current foldback mode. If a given application can drive the output voltage to ≤ Vx, during an overload, then a second criterion must be checked. Equation 7 gives the maximum input voltage, when in this mode, before damage occurs. (7) Where: Vsc is the value of output voltage during the overload. fsw is the normal switching frequency. NOTE If the input voltage should exceed this value while in foldback mode, the regulator and/or the diode may be damaged. It is important to note that the voltages in these equations are measured at the inductor. Normal trace and wiring resistance will cause the voltage at the inductor to be higher than that at a remote load. Therefore, even if the load is shorted with zero volts across its terminals, the inductor will still see a finite voltage. It is this value that should be used for Vx and Vsc in the calculations. In order to return from foldback mode, the load must be reduced to a value much lower than that required to initiate foldback. This load "hysteresis" is a normal aspect of any type of current limit foldback associated with voltage regulators. If the frequency synchronization feature is used, the current limit frequency foldback is not operational, and the system may not survive a hard short-circuit at the output. The safe operating areas, when in short circuit mode, are shown in Figure 15 through Figure 17, for different switching frequencies. Operating points below and to the right of the curve represent safe operation. NOTE Figure 15, Figure 16, and Figure 17 curves are not valid when the LM22670 is in frequency synchronization mode. Copyright © 2008–2014, Texas Instruments Incorporated Submit Documentation Feedback 13 Product Folder Links: LM22670 LM22670-Q1
Figure 15. SOA 300 kHz Figure 16. SOA 500 kHz Figure 17. SOA 800 kHz
7.4.4 Thermal Protection
temperature drops below about 135°C.
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LM22670,LM22670-Q1 www.ti.com SNVS584P –SEPTEMBER 2008–REVISED NOVEMBER 2014 Device Functional Modes (continued)
7.4.5 Duty-Cycle Limits
Ideally the regulator would control the duty cycle over the full range of zero to one. However, due to inherent delays in the circuitry, there are limits on both the maximum and minimum duty cycles that can be reliably controlled. This in turn places limits on the maximum and minimum input and output voltages that can be converted by the LM22670 device. A minimum on-time is imposed by the regulator in order to correctly measure the switch current during a current limit event. A minimum off-time is imposed in order the re-charge the bootstrap capacitor. The Equation 8 can be used to determine the approximate maximum input voltage for a given output voltage. (8) Where: Fsw is the switching frequency. TON is the minimum on-time. Both parameters are found in the Electrical Characteristics table. If the frequency adjust feature is used, that value should be used for Fsw. Nominal values should be used. The worst case is lowest output voltage, and highest switching frequency. If this input voltage is exceeded, the regulator will skip cycles, effectively lowering the switching frequency. The consequences of this are higher output voltage ripple and a degradation of the output voltage accuracy. The second limitation is the maximum duty cycle before the output voltage will "dropout" of regulation. Equation 9 can be used to approximate the minimum input voltage before dropout occurs. (9) Where: The values of TOFF and RDS(ON) are found in the Electrical Characteristics table. The worst case here is highest switching frequency and highest load. In Equation 9, RL is the dc inductor resistance. Of course, the lowest input voltage to the regulator must not be less than 4.5 V (typ). Copyright © 2008–2014, Texas Instruments Incorporated Submit Documentation Feedback 15 Product Folder Links: LM22670 LM22670-Q1
8 Application and Implementation
validate and test their design implementation to confirm system functionality.
8.1 Application Information
simplified discussion of the design process.
8.1.1 Output Voltage Divider Selection
divider as shown in Figure 18. Equation 10 can be used to calculate the resistor values of this divider. FB pin to the input of the error amplifier and 2.55 kΩ from there to ground. divider. As mentioned in Internal Loop Compensation, the -5.0 option is optimized for output voltages of 5 V. should be used to determine the resistor values in the output divider. A value of RFBB of about 1 kΩ is a good first choice. Figure 18. Resistive Feedback Divider total internal divider resistance is typically 9.93 kΩ.
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because this is a high impedance input and is susceptible to noise pick-up.
8.1.2 Power Diode
reverse voltage rating of 1.3 times the maximum input voltage.
8.2 Typical Application
8.2.1 Typical Buck Regulator Application
Figure 19 shows an example of converting an input voltage range of 5.5 V to 42 V, to an output of 3.3 V at 3 A. Figure 19. Typical Buck Regulator Application
8.2.1.1 Design Requirements
RFBT Calculated based on RFBB and VREF of 1.285 V.
8.2.1.2 Detailed Design Procedure
8.2.1.2.1 External Components
The following guidelines should be used when designing a step-down (buck) converter with the LM22670.
LM22670,LM22670-Q1 SNVS584P –SEPTEMBER 2008–REVISED NOVEMBER 2014 www.ti.com
8.2.1.2.2 Inductor
The inductor value is determined based on the load current, ripple current, and the minimum and maximum input voltages. To keep the application in continuous conduction mode (CCM), the maximum ripple current, IRIPPLE, should be less than twice the minimum load current. The general rule of keeping the inductor current peak-to- peak ripple around 30% of the nominal output current is a good compromise between excessive output voltage ripple and excessive component size and cost. Using this value of ripple current, the value of inductor, L, is calculated using Equation 12. (12) Where: Fsw is the switching frequency. Vin should be taken at its maximum value, for the given application. The formula in Equation 12 provides a guide to select the value of the inductor L; the nearest standard value will then be used in the circuit. Once the inductor is selected, the actual ripple current can be determined by Equation 13. (13) Increasing the inductance will generally slow down the transient response but reduce the output voltage ripple. Reducing the inductance will generally improve the transient response but increase the output voltage ripple. The inductor must be rated for the peak current, IPK, in a given application, to prevent saturation. During normal loading conditions, the peak current is equal to the load current plus 1/2 of the inductor ripple current. During an overload condition, as well as during certain load transients, the controller may trip current limit. In this case the peak inductor current is given by ICL, found in the Electrical Characteristics table. Good design practice requires that the inductor rating be adequate for this overload condition. NOTE If the inductor is not rated for the maximum expected current, it can saturate resulting in damage to the LM22670 and/or the power diode.
8.2.1.2.3 Input Capacitor
The input capacitor selection is based on both input voltage ripple and RMS current. Good quality input capacitors are necessary to limit the ripple voltage at the VIN pin while supplying most of the regulator current during switch on-time. Low ESR ceramic capacitors are preferred. Larger values of input capacitance are desirable to reduce voltage ripple and noise on the input supply. This noise may find its way into other circuitry, sharing the same input supply, unless adequate bypassing is provided. A very approximate formula for determining the input voltage ripple is shown in Equation 14. (14) Where: Vri is the peak-to-peak ripple voltage at the switching frequency. Another concern is the RMS current passing through this capacitor. Equation 15 determines an approximation to this current. (15) The capacitor must be rated for at least this level of RMS current at the switching frequency.
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Product Folder Links: LM22670 LM22670-Q1
voltage rating of the LM22670. the input supply that may lead to increased EMI.
8.2.1.2.4 Output Capacitor
The output capacitor is responsible for filtering the output voltage and supplying load current during transients. determines an approximation to the output voltage ripple. Typically, a total value of 100 µF or greater is recommended for output capacitance. potential output voltage overshoots as the input voltage falls below the device normal operating range. frequency. See Internal Loop Compensation for more details.
8.2.1.2.5 Boot-Strap Capacitor
it will increase switching losses and, thereby reduce efficiency.
8.2.1.3 Application Curves
Figure 20. Efficiency vs IOUT and VIN, VOUT = 3.3 V Figure 21. Switching Frequency vs RT/SYNC Resistor
9 Power Supply Recommendations
critical, but a 47 μF or 100 μF electrolytic capacitor is a typical choice.
10 Layout
10.1 Layout Guidelines
taken in layout to minimize the effect of this switching noise. switch on-state. The middle schematic shows the current flow during the FET switch off-state. 1229 SIMPLE SWITCHER® PCB Layout Guidelines (SNVA054) for more information. Figure 22. Current Flow in a Buck Application
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10.2 Layout Examples
Figure 23. PCB Layout Example for PFM Package Figure 24. PCB Layout Example for SO PowerPAD-8 Package
LM22670,LM22670-Q1 SNVS584P –SEPTEMBER 2008–REVISED NOVEMBER 2014 www.ti.com
10.3 Thermal Considerations
The components with the highest power dissipation are the power diode and the power MOSFET internal to the LM22670 regulator. The easiest method to determine the power dissipation within the LM22670 is to measure the total conversion losses then subtract the power losses in the diode and inductor. The total conversion loss is the difference between the input power and the output power. An approximation for the power diode loss is shown in Equation 17. (17) Where: VD is the diode voltage drop. An approximation for the inductor power is shown in Equation 18. (18) Where: RL is the dc resistance of the inductor. The 1.1 factor is an approximation for the ac losses. The regulator has an exposed thermal pad to aid power dissipation. Adding multiple vias under the device to the ground plane will greatly reduce the regulator junction temperature. Selecting a diode with an exposed pad will also aid the power dissipation of the diode. The most significant variables that affect the power dissipation of the regulator are output current, input voltage and operating frequency. The power dissipated while operating near the maximum output current and maximum input voltage can be appreciable. The junction-to-ambient thermal resistance of the LM22670 will vary with the application. The most significant variables are the area of copper in the PC board, the number of vias under the IC exposed pad and the amount of forced air cooling provided. A large continuos ground plane on the top or bottom PCB layer will provide the most effective heat dissipation. The integrity of the solder connection from the IC exposed pad to the PC board is critical. Excessive voids will greatly diminish the thermal dissipation capacity. See AN-2020 Thermal Design By Insight, Not Hindsight (SNVA419) for more information.
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Product Folder Links: LM22670 LM22670-Q1
11 Device and Documentation Support
11.1 Documentation Support
11.1.1 Related Documentation
- AN-1889 How to Measure the Loop Transfer Function of Power Supplies (SNVA364)
- AN-1885 LM22670 Evaluation Board (SNVA361)
- AN-1229 SIMPLE SWITCHER® PCB Layout Guidelines (SNVA054)
- AN-2020 Thermal Design By Insight, Not Hindsight (SNVA419)
11.2 Related Links
resources, tools and software, and quick access to sample or buy. Table 1. Related Links
11.3 Trademarks
WEBENCH, SIMPLE SWITCHER are registered trademarks of Texas Instruments Incorporated. All other trademarks are the property of their respective owners.
11.4 Electrostatic Discharge Caution
during storage or handling to prevent electrostatic damage to the MOS gates.
11.5 Glossary
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
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www.ti.com 15-Apr-2017 Addendum-Page 1 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Drawing Pins Package Qty Eco Plan (2) Lead/Ball Finish (6) MSL Peak Temp (3) Op Temp (°C) Device Marking (4/5) Samples 551600236-001/NOPB ACTIVE 0 1 TBD Call TI Call TI LM22670MR-5.0/NOPB ACTIVE SO PowerPAD DDA 8 95 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 L22670 5.0 LM22670MR-ADJ/NOPB ACTIVE SO PowerPAD DDA 8 95 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 L22670 ADJ LM22670MRE-5.0/NOPB ACTIVE SO PowerPAD DDA 8 250 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 L22670 5.0 LM22670MRE-ADJ/NOPB ACTIVE SO PowerPAD DDA 8 250 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 L22670 ADJ LM22670MRX-5.0/NOPB ACTIVE SO PowerPAD DDA 8 2500 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 L22670 5.0 LM22670MRX-ADJ/NOPB ACTIVE SO PowerPAD DDA 8 2500 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 L22670 ADJ LM22670QMR-5.0/NOPB ACTIVE SO PowerPAD DDA 8 95 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 L22670 Q5.0 LM22670QMR-ADJ/NOPB ACTIVE SO PowerPAD DDA 8 95 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 L22670 QADJ LM22670QMRE-5.0/NOPB ACTIVE SO PowerPAD DDA 8 250 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 L22670 Q5.0 LM22670QMRE-ADJ/NOPB ACTIVE SO PowerPAD DDA 8 250 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 L22670 QADJ LM22670QMRX-5.0/NOPB ACTIVE SO PowerPAD DDA 8 2500 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 L22670 Q5.0 LM22670QTJ-5.0/NOPB ACTIVE TO-263 NDR 7 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM22670 QTJ-5.0 LM22670QTJ-ADJ/NOPB ACTIVE TO-263 NDR 7 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM22670 QTJ-ADJ LM22670QTJE-5.0/NOPB ACTIVE TO-263 NDR 7 250 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM22670 QTJ-5.0 LM22670QTJE-ADJ/NOPB ACTIVE TO-263 NDR 7 250 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM22670 QTJ-ADJ LM22670TJ-5.0/NOPB ACTIVE TO-263 NDR 7 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM22670 TJ-5.0
www.ti.com 15-Apr-2017 Addendum-Page 2 Orderable Device Status (1) Package Type Package Drawing Pins Package Qty Eco Plan (2) Lead/Ball Finish (6) MSL Peak Temp (3) Op Temp (°C) Device Marking (4/5) Samples LM22670TJ-ADJ/NOPB ACTIVE TO-263 NDR 7 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM22670 TJ-ADJ LM22670TJE-5.0/NOPB ACTIVE TO-263 NDR 7 250 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM22670 TJ-5.0 LM22670TJE-ADJ/NOPB ACTIVE TO-263 NDR 7 250 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM22670 TJ-ADJ (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability information and additional product content details. TBD: The Pb-Free/Green conversion plan has not been defined. Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes. Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above. Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material) (3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature. (4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device. (5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation of the previous line and the two combined represent the entire Device Marking for that device. (6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish value exceeds the maximum column width. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
www.ti.com 15-Apr-2017 Addendum-Page 3 In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis. OTHER QUALIFIED VERSIONS OF LM22670, LM22670-Q1 :
- Catalog: LM22670
- Automotive: LM22670-Q1 NOTE: Qualified Version Definitions:
- Catalog - TI's standard catalog product
- Automotive - Q100 devices qualified for high-reliability automotive applications targeting zero defects
*All dimensions are nominal Device Package Type Package Drawing Pins SPQ Reel Diameter (mm) Reel Width W1 (mm) (mm) (mm) (mm) (mm) W (mm) Pin1 Quadrant LM22670MRE-5.0/NOPB SO Power PAD LM22670MRE-ADJ/NOPB SO Power PAD LM22670MRX-5.0/NOPB SO Power PAD LM22670MRX-ADJ/NOPB SO Power PAD LM22670QMRE-5.0/NOP B SO Power PAD LM22670QMRE-ADJ/NOP B SO Power PAD LM22670QMRX-5.0/NOP B SO Power PAD PACKAGE MATERIALS INFORMATION www.ti.com 23-Sep-2016 Pack Materials-Page 1
(mm) Reel Width W1 (mm) (mm) (mm) (mm) (mm) W (mm) Pin1 Quadrant LM22670QTJE-ADJ/NOP B *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM22670MRE-5.0/NOPB SO PowerPAD DDA 8 250 210.0 185.0 35.0 LM22670MRE-ADJ/NOPB SO PowerPAD DDA 8 250 210.0 185.0 35.0 LM22670MRX-5.0/NOPB SO PowerPAD DDA 8 2500 367.0 367.0 35.0 LM22670MRX-ADJ/NOPB SO PowerPAD DDA 8 2500 367.0 367.0 35.0 LM22670QMRE-5.0/NOPB SO PowerPAD DDA 8 250 210.0 185.0 35.0 LM22670QMRE-ADJ/NOP B SO PowerPAD DDA 8 250 210.0 185.0 35.0 LM22670QMRX-5.0/NOPB SO PowerPAD DDA 8 2500 367.0 367.0 35.0 LM22670QTJ-5.0/NOPB TO-263 NDR 7 1000 367.0 367.0 35.0 PACKAGE MATERIALS INFORMATION www.ti.com 23-Sep-2016 Pack Materials-Page 2
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM22670QTJ-ADJ/NOPB TO-263 NDR 7 1000 367.0 367.0 35.0 LM22670QTJE-5.0/NOPB TO-263 NDR 7 250 210.0 185.0 35.0 LM22670QTJE-ADJ/NOPB TO-263 NDR 7 250 210.0 185.0 35.0 LM22670TJ-5.0/NOPB TO-263 NDR 7 1000 367.0 367.0 35.0 LM22670TJ-ADJ/NOPB TO-263 NDR 7 1000 367.0 367.0 35.0 LM22670TJE-5.0/NOPB TO-263 NDR 7 250 210.0 185.0 35.0 LM22670TJE-ADJ/NOPB TO-263 NDR 7 250 210.0 185.0 35.0 PACKAGE MATERIALS INFORMATION www.ti.com 23-Sep-2016 Pack Materials-Page 3
www.ti.com MRA08B (Rev B)
www.ti.com TJ7A (Rev D) TOP SIDE OF PACKAGE BOTTOM SIDE OF PACKAGE
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