SM8082AAAC

Application Note: SM8082A High Efficiency, 1.5MHz, 2A Synchronous Step Down Regulator ` Features General Description The SM8082A is a high efficiency 1.5MHz synchronous step down DC/DC regulator, which is capable of delivering up to 2A output current. It can operate over a wide input voltage range from 2.5V to 5.5V and integrate main switch and synchronous switch with very low RDS(ON) to minimize the conduction loss. The low output voltage ripple, the small external inductor and the capacitor sizes are achieved with 1.5MHz switching frequency. Ordering Information SM8082 □(□□)□ Package type SOT23-5 2.5V to 5.5V Input Voltage Range 70μA Low Quiescent Current Low RDS(ON) for Internal Switches (Top/Bottom) 130mΩ /90mΩ High Switching Frequency 1.5MHz Minimizes the External Components Internal Soft-start Limits the Inrush Current 100% Dropout Operation Hic-cup for Short Circuit Protection Output Auto Discharge Function RoHS Compliant and Halogen Free Compact Package: SOT23-5        Applications Temperature Code Package Code Optional Spec Code Ordering Number SM8082AAAC    Note --     Set Top Box USB Dongle Media Player Smart phone Typical Applications Efficiency vs. Output Current L1:1.0µH VOUT:1.8V LX IN 100 CIN 10μF/6.3V Cff 22pF RH 100k COUT 10μF/10V RL 49.9k GND Figure1. Schematic Diagram Inductor and COUT Selection Table VOUT [V] 1.2/ 1.8 /3.3 95 FB EN Efficiency (%) VIN: 2.5-5.5V L [µH] 4.7 0.47 1.0 2.2 COUT [µF] 10 22 √ ☆ 2×22 √ √ √ √ √ √ Note: ‘☆’ means recommended for most applications. 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_SM8082A Rev. 0.0 © 2019 Silergy Corp. Silergy Corp. Confidential- Prepared for Customer Use Only 1 All Rights Reserved. SM8082A Pinout (Top View) EN 1 5 FB 4 IN GND 2 LX 3 (SOT23-5) Top Mark:K6xyz (device code: K6, x=year code, y=week code, z= lot number code) Pin Name Pin Number Pin Description EN 1 Enable control. Pull high to turn on. Do not leave it floating. GND 2 Ground pin. LX 3 Inductor pin. Connect this pin to the switching node of the inductor. IN 4 Input pin. Decouple this pin to the GND pin with at least a 10µF ceramic capacitor. FB 5 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=0.6×(1+RH/RL). Block Diagram IN Internal Power Current Sense Input UVLO EN LX 1.2V 0.6V FB OVP 120%VREF Control Logic Soft Start GND Thermal Detect Figure3. Block Diagram AN_SM8082A Rev. 0.0 © 2019 Silergy Corp. Silergy Corp. Confidential- Prepared for Customer Use Only 2 All Rights Reserved. AN_SM8082A Absolute Maximum Ratings (Note 1) Supply Input Voltage ---------------------------------------------------------------------------------------------- -0.3V to 6.0V FB, EN Voltage------------------------------------------------------------------------------------------- -0.3V to VIN+0.6V LX Voltage------------------------------------------------------------------------------------------------------- -0.3V(*1) to 6.0V(*2) Power Dissipation, P D @ T A = 25°C -------------------------------------------------------------------------------0.83W Package Thermal Resistance (Note 2) θ JA -------------------------------------------------------------------------------------------- ----------120°C/W θ JC ----------------------------------------------------------------------------------------------- --------------20°C/W Junction Temperature Range ------------------------------------------------------------------------------------- -40oC to 150°C Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------------ 260°C Storage Temperature Range -------------------------------------------------------------------------------------- -65°C to 150°C (*1) LX Voltage Tested Down to -3V