LT1424-5 Datasheet | Linear Technology

LT1424-5 Isolated Flyback Switching Regulator with 5V Output Features s s s s DESCRIPTIO s s s No Transformer “Third Winding” or Optoisolator Required Designed for Use with 1:1 Ratio Transformers Fixed, Application Specific 5V Output Voltage Regulation Maintained Well into Discontinuous Mode (Light Load) Load pensation Provides Excellent Load Regulation Available in 8-Pin PDIP and SO Packages Operating Frequency: 285k Hz The LT ®1424-5 is a monolithic high power switching regulator specifically designed for the isolated flyback topology. No “third winding” or optoisolator is required; the integrated circuit senses the isolated output voltage directly from the primary side flyback waveform. A high current, high efficiency switch is included on the die along with all oscillator, control and protection circuitry. The LT1424-5 operates with input supply voltages from 3V to 20V and draws only 7m A quiescent current. It can deliver up to 400m A at 5V with no external power devices. By utilizing current mode switching techniques, it provides excellent AC and DC line regulation. The LT1424-5 has a number of Features not found on other switching regulator ICs. Its unique control circuitry can maintain regulation well into discontinuous mode. Load pensation circuitry allows for improved load regulation. An externally activated shutdown mode reduces total supply current to 20µA typical for standby operation. , LTC and LT are registered trademarks of Linear Technology Corporation. U APPLICATIO S s s s Isolated munication Supplies Industrial Automation Instrumentation Systems TYPICAL APPLICATIO 5V Output Isolated Power Supply ISOLATION BARRIER 5V T1 47Ω MBRS130LT3 330p F 5.25 + C1 100µF 10V 5V 400m A 4 0.1µF 1 2 3 4 8 SHDN RCP 7 VC VIN LT1424-5 6 SYNC VSW 5 SGND PGND 1N5248 47Ω 330p F - 3 + OUTPUT VOLTAGE (V) MBR0540T4 - 1 - 2 C2 100µF 10V 1.8k 1000p F INPUT 1424-5 TA01 OUT 4.75 0 100 200 300 OUTPUT CURRENT (m A) 400 1424-5...