MP3398E MPS | Alldatasheet
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Technical content
4-String, Max 400mA/String, 80V Return, Step-Up, WLED Controller MP3398E Rev. 1.02 www.MonolithicPower.com 1 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved.
DESCRIPTION
The MP3398E is a step -up controller with four current channels designed to drive WLED arrays for large LCD panel backlighting applications. The MP3398E is able to expand the number of LED channels with two or more ICs in parallel sharing a single power source. The MP3398E employs peak-current mode with a fixed switching frequency. The frequency is programmable through an external setting resistor. The MP3398E drives an external MOSFET to boost up the output voltage from a 4.5V to 33V input supply and regulates the current in each LED string to the value set by an external current-setting resistor. The MP 3398E applies four internal current sources for current balanc ing. The current matching achieve s 2.3% regulation accuracy between strings. The low regulation voltage on the LED current sources reduces power loss. The MP 3398E supports direct PWM dimming and analog dimming with PWM input . Full protection feature s include over -current protection ( OCP), over-temperature protection (OTP), under-voltage protection ( UVP), over- voltage protection ( OVP), LED short/open protection, and inductor/diode short protection. The MP3398E is available in TSSOP-16EP and PDIP-16 packages.
FEATURES
4-String, Max 400mA/String WLED Driver 4.5V to 33V Input Voltage Range 80V ABS Rating for Each String 2.3% Current Matching Accuracy between Each String Direct PWM Dimming Mode Analog Dimming Mode with PWM Input Cascading Capability with a Single Power Source LED Open and Short Protection Programmable Recoverable Over-Voltage Protection (OVP) 202mV Latch -Off Cycle-by-Cycle Current Limit Threshold Latch-Off Over-Temperature Protection (OTP) Short Inductor/Diode Protection Available in TSSOP-16EP and PDIP -16 Packages
APPLICATIONS
Desktop LCD Flat Panel Displays All-in-One PCs 2D/3D LCD TVs All MPS parts are lead-free, halogen-free, and adhere to the RoHS directive. For MPS green status, please visit the MPS website under Quality Assurance. “MPS” and “The Future of Analog IC Technology” are registered trademarks of Monolithic Power Systems, Inc.
MP3398E – 4-STRING, 80V, STEP-UP, WLED CONTROLLER MP3398E Rev. 1.02 www.MonolithicPower.com 2 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved. TYPICAL APPLICATION VCC COMP OSC MP3398E VIN GND String 1 String 2 String 3 String 4 VOUT VIN PWM GATE ISENSE GND OVP LED1 LED2 LED3 LED4 C4 R3 ISET EN 4.5V-33V ADIM
MP3398E – 4-STRING, 80V, STEP-UP, WLED CONTROLLER MP3398E Rev. 1.02 www.MonolithicPower.com 3 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved.
ORDERING INFORMATION
Part Number Package Top Marking MP3398EGF* TSSOP-16EP See Below MP3398EGP** PDIP-16 See Below * For Tape & Reel, add suffix –Z (e.g. MP3398EGF–Z) ** For Tape & Reel, add suffix –Z (e.g. MP3398EGP–Z) TOP MARKING (MP3398EGF) MPS: MPS prefix YY: Year code WW: Week code MP3398E: Part number LLLLLL: Lot number TOP MARKING (MP3398EGP) MPS: MPS prefix YY: Year code WW: Week code MP3398E: Part number LLLLLLLL: Lot number
MP3398E – 4-STRING, 80V, STEP-UP, WLED CONTROLLER MP3398E Rev. 1.02 www.MonolithicPower.com 4 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved. PACKAGE REFERENCE TOP VIEW EN LED1 OSC LED2 OVP Exposed Pad Connect to GND ISENSE COMP ADIM LED3 GATE VCC VIN PWM GND LED4 ISET VIN LED4 VCC ISET GATE ADIM GND LED2 OSC COMP PWM LED1 LED3 OVP EN ISENSE TSSOP-16EP PDIP-16 ABSOLUTE MAXIMUM RATINGS (1) Continuous power dissipation (TA = 25° C) (2) Recommended Operating Conditions (3) Thermal Resistance (4) θJA θJC NOTES: 1) Exceeding these ratings may damage the device. 2) The maximum allowable power dissipation is a function of the maximum junction temperature T J (MAX), the junction -to- ambient thermal resistance θ JA, and the ambient temperature TA. The maximum allowable continuous power dissipation at any ambient temperature is calculated by P D (MAX) = (T J (MAX)-TA)/θJA. Exceeding the maximum allowable power dissipation produces an excessive die temperature, causing the regulator to go into thermal shutdown. Internal thermal shutdown circuitry protects the device from permanent damage. 3) The device is not guaranteed to function outside of its operating conditions. 4) Measured on JESD51-7, 4-layer PCB.
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ELECTRICAL CHARACTERISTICS
VIN = 12V, VEN = 5V, TA = 25°C, unless otherwise noted. Parameters Symbol Condition Min Typ Max Unit General Operating input voltage VIN 4.5 33 V Supply current (quiescent) IQ VIN = 12V, no switching 3.85 4.5 mA Supply current (shutdown) IST VEN = 0V, VIN = 12V 1 μA LDO output voltage VCC 7V < VIN < 28V, 0 < IVCC < 10mA 5.5 5.9 6.3 V VCC UVLO threshold VIN_UVLO Rising edge 3.7 4 4.3 V VCC UVLO hysteresis 350 mV EN high voltage VEN_HIGH VEN rising 1.5 V EN low voltage VEN_LOW VEN falling 0.6 V Step-Up Converter Gate driver sourcing impedance VCC = 5.9V,VGATE = 5.9V 4 Ω Gate driver sinking impedance VCC = 5.9V, IGATE = 10mA 2.5 Ω Switching frequency fSW ROSC = 100kΩ 305 382 460 kHz OSC voltage VOSC ROSC =100kΩ, fSW = 382kHz 0.77 0.8 0.83 V Maximum duty cycle DMAX ROSC = 100kΩ 90 % Cycle-by-cycle ISENSE current limit 180 202 224 mV COMP source current limit ICOMP SOLI 1V < COMP < 2.9V 30 μA COMP sink current limit ICOMP SILI 1V < COMP < 2.9V 18 μA COMP transconductance GCOMP ∆ICOMP = ± 10µA 120 μA/V Current Dimming PWM input low threshold VPWM_LO VPWM falling 0.4 V PWM input high threshold VPWM_HI VPWM rising 1.5 V ADIM input low threshold VADIM_LO VADIM falling 0.4 V ADIM input high threshold VADIM_HI VADIM rising 1.5 V Current Regulation ISET voltage VISET 1.95 2 2.05 V LEDX average current ILED RISET = 100.8kΩ 192 202 212 mA Current matching (5) ILED = 200mA 2.3 % LEDX regulation voltage ILED = 200mA 430 mV ILED = 60mA 285 mV
MP3398E – 4-STRING, 80V, STEP-UP, WLED CONTROLLER MP3398E Rev. 1.02 www.MonolithicPower.com 6 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved. ELECTRICAL CHARACTERISTICS (continued) VIN = 12V, VEN = 5V, TA = 25°C, unless otherwise noted. Parameters Symbol Condition Min Typ Max Unit Protection OVP threshold VOVP_OV 1.9 2.0 2.1 V OVP UVLO threshold VOVP_UV Step-up converter fails 55 mV LEDX UVLO threshold VLEDX_UV 200 mV LEDX over-voltage threshold VLEDX_OV 7.2 8 8.8 V Thermal protection threshold TST 130 °C NOTE : 5) Matching is defined as the difference between the maximum to minimum current divided by 2 times the average current.
MP3398E – 4-STRING, 80V, STEP-UP, WLED CONTROLLER MP3398E Rev. 1.02 www.MonolithicPower.com 7 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved. TYPICAL CHARACTERISTICS
MP3398E – 4-STRING, 80V, STEP-UP, WLED CONTROLLER MP3398E Rev. 1.02 www.MonolithicPower.com 8 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved. TYPICAL PERFORMANCE CHARACTERISTICS VIN = 19V, VEN = 3.3V, 120mA/string, 4 strings, 20 LEDs in series, TA = 25°C, unless otherwise noted.
MP3398E – 4-STRING, 80V, STEP-UP, WLED CONTROLLER MP3398E Rev. 1.02 www.MonolithicPower.com 9 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved. PIN FUNCTIONS TSSOP-16 Pin # PDIP-16 Pin # Name Description 1 13 LED1 LED string 1 current input. LED1 is the open -drain output of an internal dimming control switch. Connect the LED string 1 cathode to LED1. 2 14 LED2 LED string 2 current input. LED2 is the open -drain output of an internal dimming control switch. Connect the LED string 2 cathode to LED2. 3 15 GND Ground. 4 16 LED3 LED string 3 current in put. LED3 is the open -drain output of an internal dimming control switch. Connect the LED string 3 cathode to LED3. 5 1 LED4 LED string 4 current input. LED4 is the open -drain output of an internal dimming control switch. Connect the LED string 4 cathode to LED4. 6 2 ISET LED current set. Tie a current-setting resistor from ISET to ground to program the current in each LED string. 7 3 OVP Output over -voltage protection. Connect a resistor divider from output to OVP to program the OVP threshold. 8 4 OSC Switching frequency set. Connect a resistor between OSC and GND to set the step-up converter switching frequency. The clock frequency is proportional to the current source from OSC. 9 5 EN Enable control input. A voltage greater than 1. 5V turns the part on; a voltage less than 0.6V turns the part off. Do not float EN. 10 6 ISENSE Current sense input. During normal operation, ISENSE senses the voltage across the external inductor current -sensing resistor (R SENSE) for peak -current- mode control. ISENSE also limits the inductor current during every switching cycle. For cascading applications, tie ISENSE of the slave IC to GND. Do not float ISENSE. 11 7 GATE Step-up converter power switch driver output. GATE drives the external power N-channel MOSFET device. 12 8 VCC The internal 5.9V linear regulator output. VCC provides the power supply for the external MOSFET switch gate driver an d the internal control circuitry. Bypass VCC to GND with a ceramic capacitor. 13 9 VIN Supply input. VIN must be bypassed locally. 14 10 ADIM Input for analog brightness control. The LED current amplitude is determined by the duty cycle of the PWM signal applied to ADIM. An internal R-C filter (10M Ω resistor and 100pF capacitor) is integrated into ADIM. A frequency greater than 20kHz is recommended to achieve a better PWM signal filtering performance and ensure that the high-level voltage of V ADIM is above 1.5V and the low-level voltage is below 0.4V. 15 11 COMP Step-up converter compensation. COMP compensates for the regulation control loop. Connect a ceramic capacitor or a resistor and capacitor from COMP to GND. 16 12 PWM Input signal for PWM brightness control. By applying a PWM signal on PWM, the LED current is chopped, and the average current is equal to ISET x DDIM, where ISET is the LED current value set by a resistor between ISET and GND, and DDIM is the duty cycle of the PWM dimming duty cycle . Ensure that the high level voltage is above 1.5V and the low -level voltage is below 0.4V. If PWM is floating, weakly pull it to GND internally.
MP3398E – 4-STRING, 80V, STEP-UP, WLED CONTROLLER MP3398E Rev. 1.02 www.MonolithicPower.com 10 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved. BLOCK DIAGRAM Control Logic Current Sense Amplifier PWM Comparator Oscillator LED1 VREF Max Min Feedback Control LED_SHORT EA Short-String Protection Regulator LED4 OVP ISENSE VIN VCC PWM ISET COMP OSC EN Enable Control VREF GATE Current Control LEB + ILIMIT UP_CLAMP PWM Stop GND OVP Protection ProtectionOTP LED_SHORT LED_OPEN ILIMIT ADIM Figure 1: Functional Block Diagram
MP3398E – 4-STRING, 80V, STEP-UP, WLED CONTROLLER MP3398E Rev. 1.02 www.MonolithicPower.com 11 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved. OPERATION The MP 3398E is a programmable constant frequency, peak-current mode, step-up converter with 4 -channel regulated current sources to drive an array of up to four strings of white LEDs. Internal 5.9V Regulator The MP 3398E includes an internal linear regulator (VCC). When VIN is greater than 6.5V, this regulator outputs a 5.9V power supply to the external MOSFET switch gate driver and the internal control circuitry. The VCC voltage drops to 0V when the chip shuts down. The MP3398E features under -voltage lockout (UVLO). The chip is disabled until VCC exceeds the UVLO threshold. The UVLO hysteresis is approximately 350mV. System Start-Up When enabled, the MP 3398E checks the topology connection first. The chip monitors the over-voltage protection (OVP) pin to determine if the Schottky diode is connected or if the boost output is shorted to GND. An OV P voltage higher than 55mV allows the chip to switch normally; otherwise, switching is disabled. The MP3398E also checks other safety limit s, including UVLO , over-temperature protection (OTP), and over-current protection (OCP) after passing the OVP test. If all protection tests pass, the chip then begins boosting the step -up converter with an internal soft start. It is recommended that the enable signal occur after the establishment of the input voltage and PWM dimming signal during t he start -up sequence to prevent a large inrush current. Step-Up Converter At the beginning of each switching cycle, the internal clock turns on the external MOSFET . During normal operation, the minimum turn -on time is around 150ns . A stabilizing ramp added to the output of the current sense amplifier prevents sub harmonic oscillations for duty cycles greater than 50 %. This result is fed into the PWM comparator. When t he summed voltage reaches the output voltage of the error amplifier (VCOMP), the external MOSFET turns off. The output voltage of the internal error amplifier is an amplified signal of the difference between the reference voltage and the feedback voltage. The converter chooses the lowest active LEDX pin voltage automatically to prov ide a high enough bus voltage to power all of the LED arrays. If the feedback voltage drops below the reference, the output of the error amplifier increases. This results in more current flowing through the MOSFET, increasing the power delivered to the output and forming a closed loop that regulates the output voltage. Under light -load operation , especially in the case of VOUT ≈ VIN, the converter runs in pulse- skipping mode . In this mode, the MOSFET turns on for a minimum on time, and then the converter discharges the power to the output for the rem aining period. The external MOSFET remains off until the output voltage n eeds to be boosted again. Dimming Control The MP3398E provides two dimming methods: PWM and analog dimming mode. For PWM dimming, apply a PWM signal to PWM. The LED current is chopped by this PWM signal , and the average LED current is equal to ISET x DDIM, where D DIM is the duty cycle of the PWM dimming signal , and ISET is the LED current amplitude. For analog dimming, apply a PWM signal to ADIM. An internal R-C filter (10MΩ resistor and 100pF capacitor) is integrated to ADIM. This PWM signal is filtered to the DC voltage by the internal R-C filter. The LED current amplitude is equal to I SET x DDIM, where D DIM is the duty cycle of the PWM dimming signal , and ISET is the LED current amplitude. A PWM signal 20kHz or higher is recommended for better filtering. Operation Switching Frequency The converter operating frequency is set through an external resistor on OSC. This helps optimize both the size of the external components and the system efficiency.
MP3398E – 4-STRING, 80V, STEP-UP, WLED CONTROLLER MP3398E Rev. 1.02 www.MonolithicPower.com 12 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved. Open-String Protection Open-string protection is achieved through detecting the voltage of OVP and LED (1 to 4). If one or more strings are o pen, the respective LEDX pins are pulled to ground , and the IC continues charging the output voltage until it reaches the over -voltage protection (OVP) threshold. If the OVP point has been triggered, the chip stops switching and marks off the strings that have an LEDX pin voltage lower than 200mV. Once marked, the remaining LED strings force the output voltage back into tight regulation. The string with the largest voltage drop determines the output regulation. The MP3398E always attempts to light at least one string. If all strings are open, the MP3398E shuts down the step -up converter. The strings remain in this marked state until the chip resets. Short-String Protection The MP3398E monitors the LEDX pin voltages to determine if a short-string fault has occurred. If one or more strings are shorted, the respective LEDX pins tolerate high -voltage stress. If an LEDX pin voltage is higher than the protection threshold , this condition triggers the detection of a short -string fault. When a short - string fault remains for 10ms, the fault string is marked off and disabled. Once a string is marked off, it disconnects from the output voltage loop until VIN or EN restarts. To prevent mistriggering a short LED protection when the LED string is open , the short LED protection function is disabled when VLEDX of all used LED channels is higher than 2.1V. Cycle-by-Cycle Current Limit To prevent the external components from exceeding their current stress rating s, the IC employs cycle-by-cycle current -limit protection . When the current exceeds the current limit value, the IC latches off until the power resets. Short Inductor/Diode Protection When the external inductor or diode is shorted, the IC provides protection b y detecting the current flowing through the power MOSFET. When the current sense voltage across the sense resistor (connected between IS ENSE and GND) reaches the current protection threshold and lasts for eight switching cycles, the IC stops switching and latches. Thermal Shutdown To prevent the IC from operating at exceedingly high temperatures, thermal shutdown is implemented by monitoring the silicon die temperature. When the die temperature exceeds the threshold (TST), the IC latches off until the power resets.
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APPLICATION INFORMATION
Selecting the Switching Frequency The switching frequ ency of the step -up converter is recommended to be between 100kHz and 900kHz for most application s. A resistor on OSC sets the internal oscillator frequency for the step -up converter according to Equation (1): SW OSC 38200F (kHz) R ( k Ω ) (1) For R OSC = 100kΩ, the switching frequency is set to 382kHz. Setting the LED Current The current in each LED string can be set through the current setting resistor on ISET and can be calculated with Equation (2): ISET 20362ILED(mA) R ( k Ω ) (2) For RISET = 100.8kΩ, the LED current is set to 202mA. Do not leave ISET open. Selecting the Input Capacitor The input capacitor reduces the surge current drawn from the input supply and the switching noise from the device. The i nput capacitor impedance at the switching frequency should be less than the input source impedance to prevent the high -frequency switching current from passing through to the input. Ceramic capacitors with X5R or X7R dielectrics are recommended for the ir low ESR and small temperature coefficients. For most appli cations, use a 4.7μF ceramic capacitor in parallel with a 220µ F electrolytic capacitor. Selecting the Inductor and Current-Sensing Resistor A larger value inductor results in less ripple current and lower peak inductor current , which reduces stress on the N -channel MOSFET. However, the larger value inductor has a larger physical size, a higher series resistance, and a lower saturation current. Choose an inductor that will not saturate under the worst -case load conditions. Select the min imum inductor value to ensure that the boost converter works in continuous conduction mode with high efficiency and good EMI performance. Calculate the required inductance value using Equation (3) and Equation (4): OUT SW LOAD η V D (1 D)L 2 f I IN OUT V D1 V (4) Where V IN and V OUT are the input and output voltages, fSW is the switching frequency, I LOAD is the LED load current, and η is the efficiency. The switching current is used fo r peak-current- mode control. To avoid reaching the current limit, the voltage across the sensing resistor (RSENSE) must be less than 80% of the current limit voltage (VSENSE) in the worst-case scenario. Calculate RSENSE and I L(PEAK) with Equation (5) and Equation (6): SENSE L(PEAK)
0.8 VSENSER I
(5) OUT LOAD IN OUT IN L(PEAK) IN SW OUT V I V (V V )I ηV 2 L F V (6) Selecting the Power MOSFET The MP3398E is capable of driving a wide variety of N -channel power MOSFETS. The critical parameters of selection for a MOSFET are maximum drain-to-source voltage (VDS(MAX)), maximum current (ID(MAX)), on resistance (RDS(ON)), gate so urce charge (QGS) and gate drain charge (QGD), and total gate charge (QG). Ideally, the off -state voltage across the MOSFET is equal to the output voltage. Considering the voltage spike when it turns off, VDS(MAX) should be greater than 1.5 times the output voltage. The maximum current through the power MOSFET occurs at the minimum input voltage and the maximum output power. The maximum RMS current through the MOSFET is given using Equation (7) and Equation (8): RMS(MAX) IN(MAX) MAXI I D (7) OUT IN(MIN) MAX OUT VVD V (8) The current rating of the MOSFET should be greater than 1.5 x IRMS.
MP3398E – 4-STRING, 80V, STEP-UP, WLED CONTROLLER MP3398E Rev. 1.02 www.MonolithicPower.com 14 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved. The on resistance of the MOSFET determines the conduction loss, which is given by Equation (9): kRIP (on) DS RM Scond (9) Where k is the temperature coefficient of the MOSFET. The switching loss is related to Q GD and QGS1, which determine the commutation time. Q GS1 is the charge between the threshold voltage and the plateau voltage when a driver charges the gate, which can be read in the VGS vs. QG chart in the MOSFET datasheet. Q GD is the charge during the plateau voltage. These two parameters are needed to estim ate the turn -on and turn-off losses and can be calculated with Equation (10): SWINDS PLTDR GGD SWINDS THDR GGS1 SW fIVVV RQ fIVVV RQP (10) Where VTH is the threshold voltage, V PLT is the plateau voltage, VDS is the drain-source voltage, and RG is the gate resistance. RG is recommended to be 10-20Ω. Please note that calculating the switching loss is the most difficult part of loss estimation. The formula above provides a simplified equation. For more accurate estimates, the equ ation becomes much more complex. The total gate charge (QG) is used to calculate the gate drive loss and can be calculated with Equation (11): SWDRGDR fVQP (11) Where VDR is the drive voltage. Selecting the Output Capacitor The output capacitor keeps the output voltage ripple small and ensures feedback loop stability. The output capacitor impedance must be low at the switching frequency. Ceramic capacitors with X7R dielectrics are recommended for their low ESR characteristics. A 4.7μF ceramic capacitor in parallel with a 22~47 μF electrolytic capacitor is sufficient for most applications. Setting the Over-Voltage Protection (OVP) Open-string protection is achieved through the detection of the voltage on OVP. In some cases, an LED string failure results in the feedback voltage always being zero. The MP3398E continues boosting the output voltage higher and higher. If the output voltage reaches the programmed OVP threshold, t he protection is triggered. To ensure that the chip functions properly, an appropriate OVP voltage is required. The recommended OVP point is about 1.1 to 1.2 times higher than the output voltage for normal operation. The OVP voltage is set by an external resistor on OVP and can be calculated with Equation (12): HIGH OVP LOW (12) Expanding LED Channels The MP3398E can expand the number of LED channels by using two or three ICs i n parallel. To connect two ICs for a total of eight LED strings, tie the VCC pins of the master IC and the slave IC together to power the slave IC internal logic circuitry. Tie the COMP pins of the slave IC and the master IC together to regulate the voltage of all eight LED strings. The slave IC MOSFET driving signal is not used; the boost converter can be driven by the master IC only. Do not leave the ISENSE of the slave IC floating; tie it to ground. Apply the EN and DIM signals to both ICs. PCB Layout Guidelines Efficient PCB layout is critical for stable operation and r educing EMI noise. For best results, follow the guidelines below: 1. Ensure that the loop among the external MOSFET, the output diode, and the output ceramic capacitor is as small and short as possible since it carries a high -frequency pulse current. 2. Separate the power ground (PGND) and signal ground (GND) to reduce noise affection. 3. Connect PGND and GND together. All logic signals refer to the signal ground. 4. Place ceramic capacitors as close to VIN and VCC as possible.
MP3398E – 4-STRING, 80V, STEP-UP, WLED CONTROLLER MP3398E Rev. 1.02 www.MonolithicPower.com 15 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved. TYPICAL APPLICATION CIRCUIT Figure 2: 4-String, 20 LEDs in Series, 120mA/String Application NOTE: Some components are reasonably adjustable based on real cases.
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PACKAGE INFORMATION
PACKAGE OUTLINE DRAWING FOR 16-TSSOP w/ EXPOSED PADDLE MF-PO-D-0036 revision 3.0 FRONT VIEW SIDE VIEW BOTTOM VIEW DETAIL "A" NOTE: 1) ALL DIMENSIONS ARE IN MILLIMETERS. 2) PACKAGE LENGTH DOES NOT INCLUDE MOLD FLASH, PROTRUSION OR GATE BURR. 3) PACKAGE WITDH DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSION. 4) LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.10 MILLIMETERS MAX. 5) DRAWING CONFORMS TO JEDEC MO-153, VARIATION ABT. 6) DRAWING IS NOT TO SCALE. PIN 1 ID TOP VIEW RECOMMENDED LAND PATTERN SEE DETAIL "A"
MP3398E – 4-STRING, 80V, STEP-UP, WLED CONTROLLER NOTICE: The information in this document is subject to change without notice. Please contact MPS for current specifications. Users should warrant and guarantee that third party I ntellectual Property rights are not infringed upon when integrating MPS products into any application. MPS will not assume any legal responsibility for any said applications. MP3398E Rev. 1.02 www.MonolithicPower.com 17 7/31/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2017 MPS. All Rights Reserved. PACKAGE INFORMATION (continued) PDIP-16