SQ28903BAT

High-Efficiency, 6V, 3A 2.2MHz Synchronous Step-Down Regulator

SQ28903BAT High-Efficiency, 6V, 3A 2.2MHz Synchronous Step-Down Regulator Datasheet

Parameters
Features
Description

Part number	SQ28903BAT
Channel(#)	1
Vin (min) (V)	2.8
Vin (max) (V)	6
Switching frequency (min)(kHz)	2200
Switching frequency (max)(kHz)	2200
Vout (min) (V)	0.6
Vout (max) (V)	6
Iout (max) (A)	3
Vout2 (min)(V)
Vout2 (max )(V)
Iout2 (max)(A)
Vref accuracy (±%)	1%
Vout accuracy(±%)
Control mode	Peak current control
Duty cycle (max)(%)	100
Operation mode	PFM/FCCM
Iq (typ) (uA)	35
Features	Enable, Power good, Auto-discharge, Fixed soft-start, Low Iq, UVP with hiccup, 100% duty cycle, Low ISD, Spread spectrum, Cycle by cycle overcurrent protection, Forced PWM, Pre-bias startup
Package	SOT583
Operating temperature range(°C)	-40 to 125
Functional safety category

• 2.8V~6V Input Voltage Range

• Up to 3A Output Current Capability

• Low RDS(ON) for Internal Switches (Top/Bottom): 65mΩ/25mΩ

• Constant Frequency Peak Current Mode Control

• 38µA Quiescent Current (Typ.)

• 2.5µA Shutdown Current (Typ.)

• ±1% 0.6V Reference Over -40°C to +125°C

• 2.2MHz Switching Frequency

• Internal Soft-Start Limits Inrush Current

• Forced PWM or PFM Operation Selectable in Light Load

• 100% Duty Cycle Dropout Operation

• Spread Spectrum Clocking

• Power-Good Indicator

• Hiccup Mode for Short-Circuit Protection

• Compact SOT583 Package

• MSL Rating: MSL1

The SQ28903 is a high-efficiency 2.2MHz synchronous step-down converter that operates over an input voltage range of 2.8V to 6V, and can deliver an output current of up to 3A. It integrates very low RDS(ON) main and synchronous MOSFETs to minimize conduction loss. The 2.2MHz constant switching frequency reduces the required external inductor and capacitor values.

The SQ28903 utilizes a constant frequency peak current mode control architecture to achieve stable operation across a wide range of conditions. It also provides cycle-by-cycle current limit protection, output short-circuit protection, and overtemperature protection.

The SQ28903 is available in a space-saving, SOT583 package.

Evaluation Board

Photo of evaluation board
Photo of evaluation board
Photo of evaluation board

EVB_SQ28903BAT

EVB File

The EVB_SQ28903BAT is intended for evaluating 6V/3A 2.2MHz synchronous step-down regulator.

Technical Documentation

Title	Date
Silergy_Catalog_Q2_2026	2026-06-12