SQ28703SYD

Application Note: SQ28703 High Efficiency, 2.4MHz, 3A Synchronous Step Down Regulator ` Features    Ordering Information   SQ28703 □(□□□ )   Package Code  Optional Spec Code Package type DFN2×2-7 rep are Ordering Number SQ28703SYD  Note -- Applications lP   de nti a   Set Top Box USB Dongle Media Player Smart Phone orp OUT yC PG VOUT:1.2V 95 RH 80.6k FB ON/ OFF EN Sil erg GND Figure1. Schematic Diagram RL 162k COUT 22μF Efficiency (%) LX VIN RPG 100k Efficiency vs. Output Current (IOUT=0~3A, L=0.47μH/0420CDMCCDS-R47MC) 100 L1:0.47µH VIN: 2.5-6.0V CIN 10μF .C on fi Typical Applications 2.5~6.0V Input Voltage Range 23μA Low Quiescent Current Low RDS(ON) for Internal Switches (Top/Bottom) 31mΩ /23mΩ Instant PWM Control Achieve Ultra Fast Dynamic Response 2.4MHz Switching Frequency Minimizes the External Components Internal Soft-start Limits the Inrush Current 100% Drop Out Operation Output Auto Discharge Function Hiccup Mode for Short Circuit Protection RoHS Compliant and Halogen Free Compact Package: DFN2×2-7 RO N  IR IT  or K The SQ28703 is a high efficiency 2.4MHz synchronous step down DC/DC regulator which is capable of delivering up to 3A output currents. It can operate over a wide input voltage range from 2.5V to 6V and integrates main switch and synchronous switch with very low RDS(ON) to minimize the conduction loss. dF General Description 90 85 80 VIN=3.3V,VOUT=1.8V VIN=4.2V,VOUT=1.8V VIN=5.0V,VOUT=1.8V 75 70 0.001 0.01 0.1 1 10 Output Current (A) Figure2. Efficiency vs. Output Current AN_SQ28703 Rev.0.9 © 2020 Silergy Corp. Silergy Corp. Confidential- Prepared for Customer Use Only 1 All Rights Reserved. SQ28703 EN 1 PG 2 FB 3 OUT 4 7 VIN 6 LX 5 GND RO N Pinout (Top View) (DFN2×2-7) Pin Number 1 FB 3 OUT GND LX 4 5 6 IN 7 2 Pin Description Enable control. Pull high to turn on. or K Pin Name EN PG IR IT Top Mark: 7Gxyz (device code: 7G, x=year code, y=week code, z= lot number code) Power good indicator. de nti a Absolute Maximum Ratings (Note 1) lP rep are dF Output feedback pin. Connect this pin to the center point of the output resistor divider (as shown in Figure 1) to program the output voltage: VOUT=0.8×(1+RH/RL). Output voltage feedback pin, connect to the output capacitor side. Ground pin. Inductor pin. Connect this pin to the switching node of the inductor. Input pin. Decouple this pin to the GND pin with at least a 10µF ceramic capacitor. on fi Supply Input Voltage ------------------------------------------------------------------------------------------------- -0.3V to 7.0V EN, PG, FB, OUT---------------------------------------------------------------------------------------------- -0.3V to VIN + 0.3V LX Voltage------------------------------------------------------------------------------------------------- -0.3V（*1） to 6.5V（*2） Power Dissipation, PD @ TA = 25°C, DFN2×2-7 ----------------------------------------------------------------------------------------------------------- 2.86W Package Thermal Resistance (Note 2) .C θ JA ----------------------------------------------------------------------------------------------------------------- 35°C/W θ JC ----------------------------------------------------------------------------------------------------------------- 10°C/W erg yC orp Junction Temperature Range ---------------------------------------------------------------------------------------- -40°C~150°C Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------------- 260°C Storage Temperature Range --------------------------------------------------------------------------------------- -65°C to 150°C (*1) LX Voltage Tested Down to -3V