Catalog
Secondary-Side Optocoupler Driver
Key Features
• 600mV Reference (1.25% Over Temperature)
• Wide Input Supply Range: 3V to 20V
• Overshoot Control Function Prevents OutputOvershoot on Start-Up and Short-Circuit Recovery
• High Bandwidth Error Amplifier Permits Simple LoopFrequency Compensation
• Ground-Referenced Opto-Coupler Drive
• 10mA Opto-Coupler Drive with Current Limiting
• Low Profile (1mm) ThinSOT™Package
Description
AI
The LT4430 drives the opto-coupler that crosses the galvanic barrier in an isolated power supply. The IC contains a precision-trimmed reference, a high bandwidth error amplifier, an inverting gain of 6 stage to drive the optocoupler and unique overshoot control circuitry.The LT4430’s 600mV reference provides ±0.75% initial accuracy and ±1.25% tolerance over temperature. A high bandwidth 9MHz error amplifier permits simple frequency compensation and negligible phase shift at typical loop crossover frequencies. The opto-coupler driver provides 10mA of output current and is short-circuit protected. A unique overshoot control function prevents output overshoot on start-up and short-circuit recovery with a single capacitor.The LT4430 is available in the low profile 6-lead TSOT-23 package.Applications48V Input Isolated DC/DC ConvertersIsolated Telecommunication Power SystemsDistributed Power Step-Down ConvertersOffline Isolated Power SuppliesIndustrial Control SystemsAutomotive and Heavy Equipment