MP2181 1A, Synchronous, Step-Down Converter with SS & PG DESCRIPTION FEATURES The MP2181 is a monolithic, step-down, switch- Low I : 21A Q mode converter with built-in internal power 1.2MHz Switching Frequency MOSFETs. It achieves 1A continuous output EN for Power Sequencing current from a 2.5V to 5.5V input voltage with 1% FB Accuracy excellent load and line regulation. The output Wide 2.5V to 5.5V Operating Input Range voltage can be regulated to as low as 0.6V. Output Adjustable from 0.6V Up to 1A Output Current The constant-on-time (COT) control scheme 90m and 50m Internal Power MOSFET provides fast transient response and eases loop stabilization. Fault protections include cycle-by- Switches cycle current limiting and thermal shutdown. 100% Duty On Output Discharge The MP2181 is available in an ultra-small V OVP O SOT583 package, and requires a minimal External Soft-Start Control number of readily available, standard external Short-Circuit Protection with Hiccup Mode components. Power Good The MP2181 is ideal for a wide range of Available in a SOT583 Package applications including high-performance DSPs, wireless power, portable and mobile devices, APPLICATIONS and other low-power systems. Wireless/Networking Cards Portable Instruments Battery Powered Devices Low-Voltage I/O System Power Multi-Function Printer All MPS parts are lead-free and adhere to the RoHS directive. For MPS green status, please visit the MPS website under Quality Assurance. MPS, the MPS logo, and Simple, Easy Solutions are registered trademarks of Monolithic Power Systems, Inc. or its subsidiaries. TYPICAL APPLICATION Efficiency vs. Output Current L1 VIN VOUT L = 1H (DCR = 27m) 1H 5V 1.2V/1A SW 100 VIN C1 OUT C2 95 10 F 22F R1 90 100k MP2181 EN EN FB 85 R2 SS SS 100k 80 PG C3 Vin=2.5V,Vo=1.2V 2.2nF 75 Vin=3.6V,Vo=1.2V GND Vin=5V,Vo=1.2V 70 0.001 0.01 0.1 1 OUTPUT CURRENT(A) MP2181 Rev. 1.0 www.MonolithicPower.com 1 5/9/2019 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. 2019 MPS. All Rights Reserved. EFFICIENCY(%)MP2181 1A, SYNCHRONOUS, STEP-DOWN SWITCHER WITH SS & PG ORDERING INFORMATION Part Number* Package Top Marking MP2181GTL SOT583 See Below * For Tape & Reel, add suffix Z (e.g. MP2181GTLZ). TOP MARKING BEV: Product code of MP2181GTL Y: Year code LLL: Lot number PACKAGE REFERENCE TOP VIEW 1 8 FB PG VIN OUT SW SS GND 4 EN 5 SOT583 PIN FUNCTIONS Pin Name Description 1 PG Power good indicator. The output of this pin is an open drain. Supply voltage. The MP2181 operates from a +2.5V to +5.5V unregulated input. A decoupling 2 VIN capacitor is needed to prevent large voltage spikes from appearing at the input. Output switching node. SW is the drain of the internal high-side P-Channel MOSFET. Connect 3 SW the inductor to SW to complete the converter. 4 GND Ground. 5 EN On/off control. Soft start. Connect a capacitor across SS and GND to set the soft-start time, and to avoid start- 6 SS up inrush current. Output voltage power rail and input sense pin for output voltage. Connect load to this pin. 7 OUT An output capacitor is needed to decrease the output voltage ripple. Feedback pin. An external resistor divider from the output to GND, tapped to the FB pin, sets 8 FB the output voltage. MP2181 Rev. 1.0 www.MonolithicPower.com 2 5/9/2019 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. 2019 MPS. All Rights Reserved.