MP2161 MPS | Alldatasheet

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MP2161 2A, 6V, 1.5MHz, 17μA IQ, COT Synchronous Step Down Switcher In 8-pin TSOT23 MP2161 Rev. 1.03 www.MonolihicPower.com 1 9/6/2013 MPS Proprietary Information. Patent Protec ted. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. The Future of Analog IC Technology

DESCRIPTION

The MP2161 is a monolithic step-down switch mode converter with built-in internal power MOSFETs. It achieves 2A continuous output current from a 2.5V to 6V input voltage with excellent load and line regulation. The output voltage can be regulated as low as 0.6V. The Constant-On-Time control scheme provides fast transient response and eases loop stabilization. Fault condition protection includes cycle-by-cycle current limiting and thermal shutdown. The MP2161 is available in the small TSOT23-8 package and requires a minimum number of readily available standard external components. The MP2161 is ideal for a wide range of applications including High Performance DSPs, FPGAs, PDAs, and portable instruments.

FEATURES

  • Very Low I Q: 17μA
  • Default 1.5MHz Switching Frequency
  • EN and Power Good for Power Sequencing
  • Wide 2.5V to 6V Operating Input Range Output Adjustable from 0.6V
  • Up to 2A Output Current
  • 100% Duty Cycle in Dropout
  • 100m Ω and 60mΩ Internal Power MOSFET Switches
  • Cycle-by-Cycle Over Current Protection
  • Short Circuit Protect with Hiccup Mode
  • Stable with Low ESR Output Ceramic Capacitors
  • Available in a TSOT23-8 Package

APPLICATIONS

  • Wireless/Networking Cards
  • Portable Instruments
  • Battery Powered Devices
  • Low Voltage I/O System Power All MPS parts are lead-free and adhere to the RoHS directive. For MPS green status, please visit MPS website under Products, Quality Assurance page. “MPS” and “The Future of Analog IC Technology” are registered trademarks of Monolithic Power Systems, Inc. TYPICAL APPLICATION

MP2161 – 2A, 6V, 1.5MHz SYNCHRONOUS STEP-DOWN SWITCHER MP2161 Rev. 1.03 www.MonolihicPower.com 2 9/6/2013 MPS Proprietary Information. Patent Protec ted. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved.

ORDERING INFORMATION

Part Number* Package Top Marking MP2161GJ TSOT23-8 AEB * For Tape & Reel, add suffix –Z (e.g. MP2161GJ–Z); PACKAGE REFERENCE PG VIN SW PGND EN FB AGND OUT TOP VIEW TSOT23-8 ABSOLUTE MAXIMUM RATINGS (1) -0.3V (-1.5V for <10ns) to 6.5V (7V for <10ns) Continuous Power Dissipation (TA = +25°C) (2) Recommended Operating Conditions (3) Operating Junction Temp. (TJ). -40°C to +125°C 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 θJA, 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 powe r dissipation will cause excessive die temperature, and the regulator will 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.

MP2161 – 2A, 6V, 1.5MHz SYNCHRONOUS STEP-DOWN SWITCHER MP2161 Rev. 1.03 www.MonolihicPower.com 3 9/6/2013 MPS Proprietary Information. Patent Protec ted. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. ELECTRICAL CHARACTERISTICS (5) VIN = 5V, TA = +25°C, unless otherwise noted. Parameter Symbol Condition Min Typ Max Units 2.5V ≤ VIN ≤ 6V -3% 0.600 +3%Feedback Voltage V FB V/% Feedback Current I FB V FB = 0.6V 10 50 nA PFET Switch On Resistance R DSON_P 100 m Ω NFET Switch On Resistance R DSON_N 60 m Ω Switch Leakage VEN = 0V, VIN = 6V VSW = 0V and 6V 0 1 μA PFET Current Limit 2.7 3.2 4.0 A VIN=5V, VOUT=1.2V 185 ON Time T ON VIN=3.6V, VOUT=1.2V 245 ns VOUT=1.2V -20% 1500 +20% kHz/%Switching frequency F s TA=-40oC to +85oC(6) -25% 1500 +25% kHz/% Minimum Off Time T MIN-OFF 60 ns Soft-Start Time T SS-ON 1.5 ms Power Good Upper Trip Threshold PG H FB voltage respect to the regulation +10 % Power Good Lower Trip Threshold PG L -10 % Power Good Delay PG D 50 μs Power Good Sink Current Capability VPG-L Sink 1mA 0.4 V Power Good Logic High Voltage V PG-H V IN=5V, VFB=0.6V 4.9 V Power Good Internal Pull Up Resistor RPG 550 k Ω Under Voltage Lockout Threshold Rising 2.15 2.3 2.45 V Under Voltage Lockout Threshold Hysteresis 260 mV EN Input Logic Low Voltage 0.4 V EN Input Logic High Voltage 1.2 V VEN=2V 1.5 μA EN Input Current VEN=0V 0 μA Supply Current (Shutdown) V EN=0V, VIN=3V 20 100 nA Supply Current (Quiescent) V EN=2V, VFB=0.63V, VIN=5V 17 20 μA Thermal Shutdown(5) 150 °C Thermal Hysteresis(5) 30 °C Notes: 5) Guaranteed by design. 6) Guaranteed by characterization test.

MP2161 – 2A, 6V, 1.5MHz SYNCHRONOUS STEP-DOWN SWITCHER MP2161 Rev. 1.03 www.MonolihicPower.com 4 9/6/2013 MPS Proprietary Information. Patent Protec ted. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. TYPICAL PERFORMANCE CHARACTERISTICS VIN = 5V, VOUT = 1.2V, L = 1.0µH, TA = +25ºC, unless otherwise noted. Quiescent Current vs. Input Voltage Shutdown Current vs. Input Voltage Load Regulation Line Regulation Case Temp Rise VIN=3V, VOUT=1.2V Case Temp Rise VIN=5V, VOUT=3.3V Efficiency 2 2.5 3 3.5 4 4.5 5 5.5 6 INPUT VOLTAGE (V) 0.0005 0.001 0.0015 0.002 0.0025 0.003 2 2.5 3 3.5 4 4.5 5 5.5 6 INPUT VOLTAGE (V) -2.00 -1.50 -1.00 -0.50 0.00 0.50 1.00 1.50 2.00 0 0.5 1 1.5 2 2.5 LOAD CURRENT (A) VIN=5V VIN=6V -1.00 -0.80 -0.60 -0.40 -0.20 0.00 0.20 0.40 0.60 0.80 1.00 23456 INPUT VOLTAGE (V) Load=1A Load=2A Load=0A 0 0.5 1 1.5 2 2.5 OUTPUT CURRENT (A) 0 0.5 1 1.5 2 2.5 OUTPUT CURRENT (A) 100 1 10 100 1000 10000 LOAD CURRENT(mA) VIN=3.3V VIN=5V VIN=6V IOUT (A) Efficiency 5/3.3VIN to 1.8VOUT Efficiency 5VIN to 3.3VOUT IOUT (A) 100 0 0.5 1 1.5 2 2.5 VIN=5V V IN=3.3V 100 0 0.5 1 1.5 2 2.5

MP2161 – 2A, 6V, 1.5MHz SYNCHRONOUS STEP-DOWN SWITCHER MP2161 Rev. 1.03 www.MonolihicPower.com 5 9/6/2013 MPS Proprietary Information. Patent Protec ted. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. TYPICAL PERFORMANCE CHARACTERISTICS (continued) VIN = 5V, VOUT = 1.2V, L = 1.0µH, TA = +25ºC, unless otherwise noted.

MP2161 – 2A, 6V, 1.5MHz SYNCHRONOUS STEP-DOWN SWITCHER MP2161 Rev. 1.03 www.MonolihicPower.com 6 9/6/2013 MPS Proprietary Information. Patent Protec ted. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. TYPICAL PERFORMANCE CHARACTERISTICS (continued) VIN = 5V, VOUT = 1.2V, L = 1.0µH, TA = +25ºC, unless otherwise noted

MP2161 – 2A, 6V, 1.5MHz SYNCHRONOUS STEP-DOWN SWITCHER MP2161 Rev. 1.03 www.MonolihicPower.com 7 9/6/2013 MPS Proprietary Information. Patent Protec ted. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. PIN FUNCTIONS Pin # Name Description 1 PG Power Good Indicator. The output of this pin is an open drain with internal pull up resistor to IN. PGOOD is pulled up to IN when the FB voltage is within 10% of the regulation level, if FB voltage is out of that regulation range, it is LOW. 2 VIN Supply Voltage. The MP2161 operates from a +2.5V to +6V unregulated input. C1 is needed to prevent large voltage spikes from appearing at the input.

3 SW Switch Output

4 PGND Power ground

5 OUT Input sense pin for output voltage

6 AGND Analogy ground for internal control circuit

7 FB Feedback pin. An external resistor divider fr om the output to GND, tapped to the FB pin, sets the output voltage.

8 EN On/Off Control

MP2161 – 2A, 6V, 1.5MHz SYNCHRONOUS STEP-DOWN SWITCHER MP2161 Rev. 1.03 www.MonolihicPower.com 8 9/6/2013 MPS Proprietary Information. Patent Protec ted. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. BLOCK DIAGRAM Main Switch (PCH ) Synchronous Rectifier (N C H ) Constant On- Time Pulse PWM Bias Voltage Reference 0.6V EN FB SW COMP VIN FBCOMP EN Driver PDRV NDRV Soft start GND OUT PWM COMP COMP 0. 66V 0. 54V PG Hi-Z FB for fixed output IN E.A. Ramp generator COMP VOUT RST SW Lo-Iq Lo-Iq Lo-Iq Lo-Iq Lo-Iq VTH Figure 1: MP2161 Block Diagram

MP2161 – 2A, 6V, 1.5MHz SYNCHRONOUS STEP-DOWN SWITCHER MP2161 Rev. 1.03 www.MonolihicPower.com 9 9/6/2013 MPS Proprietary Information. Patent Protec ted. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. OPERATION MP2161 uses constant on-time control with input voltage feed forward to stabilize the switching frequency over full input range. At light load, MP2161 employs a proprietary control of low side switch and inductor current to eliminate ringing on switching node and improve efficiency. Constant On-time Control Compare to fixed frequency PWM control, constant on-time control offers the advantage of simpler control loop and faster transient response. By using input voltage feed forward, MP2161 maintains a nearly constant switching frequency across input and output voltage range. The on- time of the switching pulse can be estimated as: OUT ON IN VT0 . 6 6 7 sV=⋅μ To prevent inductor current run away during load transient, MP2161 fixes the minimum off time to be 60ns. However, this minimum off time limit will not affect operation of MP2161 in steady state in any way. Light Load Operation In light load condition, MP2161 uses a proprietary control scheme to save power and improve efficiency. The MP2161 will turn off the low side switch when inductor current starts to reverse. Then MP2161 works in discontinuous conduction mode (DCM) operation. Enable When input voltage is greater than the under- voltage lockout threshold (UVLO), typically 2.3V, MP2161 can be enabled by pulling EN pin to higher than 1.2V. Leaving EN pin float or pull down to ground will disable MP2161. There is an internal 1Meg Ohm resistor from EN pin to ground. Soft Start MP2161 has built-in soft start that ramps up the output voltage in a controlled slew rate, avoiding overshoot at startup. The soft start time is about 1.5ms typical. Power GOOD Indictor MP2161 has an open drain with 550k Ω pull-up resistor pin for power good indicator PGOOD. When FB pin is within +/-10% of regulation voltage, i.e. 0.6V, PGOOD pin is pulled up to IN by the internal resistor. If FB pin voltage is out of the +/-10% window, PGOOD pin is pulled down to ground by an internal MOS FET. The MOS FET has a maximum R dson of less than 100 Ohm. Current limit MP2161 has a typical 3.2A current limit for the high side switch. When the high side switch hits current limit, MP2161 will touch the hiccup threshold until the current lower down. This will prevent inductor current from continuing to build up which will result in damage of the components. Short Circuit and Recovery MP2161 enters short circuit protection mode also when the current limit is hit, and tries to recover from short circuit with hiccup mode. In short circuit protection, MP2161 will disable output power stage, discharge soft-start cap and then automatically try to soft-start again. If the short circuit condition still holds after soft- start ends, MP2161 repeats this operation cycle till short circuit disappears and output rises back to regulation level.

MP2161 – 2A, 6V, 1.5MHz SYNCHRONOUS STEP-DOWN SWITCHER MP2161 Rev. 1.03 www.MonolihicPower.com 10 9/6/2013 MPS Proprietary Information. Patent Protec ted. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved.

APPLICATION INFORMATION

Setting the Output Voltage The external resistor divider is used to set the output voltage (see Typical Application on page 1). The feedback resistor R1 can not be too large neither too small considering the trade-off for stability and dynamic. Choose R1 to be around 120kΩ to 200kΩ. R2 is then given by: out R1R2 V 10.6 The feedback circuit is shown as Figure 2. Vout FB MP2161 Figure 2: Feedback Network Table 1 lists the recommended resistors value for common output voltages. Table 1—Resistor Selection for Common Output Voltages VOUT (V) R1 (k Ω) R2 (k Ω) Selecting the Inductor A 0.68µH to 2.2µH inductor is recommended for most applications. For highest efficiency, the inductor DC resistance should be less than 15mΩ. For most designs, the inductance value can be derived from the following equation. OUT IN OUT IN L OSC V( V V )L VI f ×−= ×Δ × Where ΔIL is the inductor ripple current. Choose inductor current to be approximately 30% of the maximum load current. The maximum inductor peak current is: III L LOAD)MAX(L Δ+= Selecting the Input Capacitor The input current to the step-down converter is discontinuous, therefore a capacitor is required to supply the AC current to the step-down converter while maintaining the DC input voltage. Use low ESR capacitors for the best performance. Ceramic capacitors with X5R or X7R dielectrics are highly recommended because of their low ESR and small temperature coefficients. For most applications, a 10µF capacitor is sufficient. For higher output voltage, 47uF may be needed for more stable system. Since the input capacitor absorbs the input switching current it requires an adequate ripple current rating. The RMS current in the input capacitor can be estimated by: × −×= IN OUT IN OUTLOAD1C V V1V VII The worse case condition occurs at VIN = 2VOUT, where: II LOAD 1C = For simplification, choose the input capacitor whose RMS current rating greater than half of the maximum load current. The input capacitor can be electrolytic, tantalum or ceramic. When using electrolytic or tantalum capacitors, a small and high quality ceramic capacitor, i.e. 0.1μF, should be placed as close to the IC as possible. When using ceramic capacitors, make sure that they have enough capacitance to provide sufficient charge to prevent excessive voltage ripple at input. The input voltage ripple caused by capacitance can be estimated by: LOAD OUT OUT IN INSI N IV VV1 fC 1V V

MP2161 – 2A, 6V, 1.5MHz SYNCHRONOUS STEP-DOWN SWITCHER MP2161 Rev. 1.03 www.MonolihicPower.com 12 9/6/2013 MPS Proprietary Information. Patent Protec ted. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved. TYPICAL APPLICATION CIRCUITS Figure 4: Typical Application Circuit

MP2161 – 2A, 6V, 1.5MHz SYNCHRONOUS STEP-DOWN SWITCHER NOTICE: The information in this document is subject to change wi thout notice. Please contact M PS for current specifications. Users should warrant and guarantee that third party Intellectual Property rights ar e not infringed upon when integrating MPS products into any application. MPS will not assume any legal responsibility for any said applications. MP2161 Rev. 1.03 www.MonolithicPower.com 13 9/6/2013 MPS Proprietary Information. Patent Protec ted. Unauthorized Photocopy and Duplication Prohibited. © 2013 MPS. All Rights Reserved.

PACKAGE INFORMATION

NOTE: 1) ALL DIMENSIONS ARE IN MILLIMETERS . 2) PACKAGE LENGTH DOES NOT INCLUDE MOLD FLASH , PROTRUSION OR GATE BURR . 3) PACKAGE WIDTH DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSION . 4) LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.10 MILLIMETERS MAX . 5) JEDEC REFERENCE IS MO -193, VARIATION BA . 6) DRAWING IS NOT TO SCALE . 7) PIN 1 IS LOWER LEFT PIN WHEN READING TOP MARK FROM LEFT TO RIGHT, (SEE EXAMPLE TOP MARK ) TOP VIEW RECOMMENDED LAND PATTERN SEATING PLANE SIDE VIEW DETAIL ''A'' SEE DETAIL ''A'' IAAAA PIN 1 ID See note 7 EXAMPLE TOP MARK