Si91871

The Si91871 is a 300-mA CMOS LDO (low dropout) voltage regulator. It is the perfect choice for low voltage, low power applications. An ultra low ground current makes this part attractive for battery operated power systems.It also offers ultra low dropout voltage to prolong battery life in portable electronics. Systems requiring a quiet voltage source, such as RF applications, will benefit from the Si91871's ultra low output noise. An external noise bypass capacitor connected to the device's BP pin can further reduce the noise level. The Si91871 is designed to maintain regulation while delivering 400-mA peak current, making it ideal for systems that have a high surge current upon turn-on.

For better transient response and regulation, an active pull-down circuit is built into the Si91871 to clamp the output voltage when it rises beyond normal regulation. The Si91871 automatically discharges the output voltage by connecting the output to ground through a 100- n-channel MOSFET when the device is put in shutdown mode.

The Si91871 features reverse battery protection to limit reverse current flow to approximately 1-A in the event reversed battery is applied at the input, thus preventing damage to the IC.

The Si91871 is available in the 5-pin MLP33 PowerPAK package and is specified to operate over the industrial temperature range of -40⁰C to 85⁰