LM7705MMX/NOPB

The LM7705 device is a switched-capacitor voltage inverter with a -0.23V low-noise fixed negative voltage regulator. This device is specifically designed for low-voltage amplifiers to enable the amplifier output to approach zero voltage. The -0.23V is used to power the negative supply pin of the amplifier while maintaining the voltage of the entire amplifier below 5.5V. When operating with a single supply voltage, rail-to-rail output amplifiers cannot output zero voltage, and cumulative errors occur because the amplifier output saturation voltage is amplified by the following gain stages. A small negative supply voltage prevents the amplifier output from saturating at zero voltage and helps maintain an accurate zero voltage through the signal processing chain. Moreover, when using an amplifier to drive an ADC input, the amplifier can output a zero-voltage signal and utilize the full ADC input range. The LM7705 device features a shutdown pin to minimize standby power consumption.

Applications

• True zero amplifier output
• Portable instrumentation
• Low-voltage split supply

Key features

• Regulated output voltage: 0.232V
• Output voltage tolerance: 5%
• Output ripple voltage: 4mVPP
• Supply voltage: 3V to 5.25V
• Conversion efficiency up to 98%
• Quiescent current: 78μA
• Shutdown current: 20nA
• Start-up time: 500μs
• Operating temperature range: -40°C to 125°C
• 8-pin VSSOP package