SN6505ADBVR | Texas Instruments

Transformer Driver, SN6505ADBVR, Texas Instruments

The SN6505ADBVR is a low-noise, low-EMI push-pull transformer driver, specifically designed for small form-factor, isolated power supplies. It drives low-profile, center-tapped transformers from a 2.25 V to 5 V DC power supply. Ultra-low noise and EMI are achieved through slew-rate control of the output switch voltage and Spread Spectrum Clocking (SSC). The SN6505ADBVR consists of an oscillator followed by a gate drive circuit that provides complementary output signals to drive ground-referenced N-channel power switches. The device includes two 1-A Power-MOSFET switches to ensure start-up under heavy loads. The switching clock can also be provided externally for accurate placement of switcher harmonics or when operating multiple transformer drivers. Internal protection features include 1.7 A current limiting, under-voltage lockout, thermal shutdown, and break-before-make circuitry. The SN6505ADBVR also includes a soft-start feature to prevent high inrush current during power-up with large load capacitors. The SN6505ADBVR has a 160 kHz internal oscillator for applications that need to minimize emissions, while the SN6505ADBVR has a 420 kHz internal oscillator for applications that require higher efficiency and smaller transformer size.

Features

• Ultra-low EMI
• Spread spectrum clocking
• Synchronization of multiple devices with external clock input
• Slew-rate control
• Thermal shutdown
• Soft-start to reduce In-rush current

Applications

• Low-noise isolated USB supplies
• Process control
• Telecom supplies
• Radio supplies
• Distributed supplies
• Medical instruments
• Precision instruments
• Low-noise filament supplies