The LP3985 is designed for portable and wireless applications with demanding performance and space requirements.
The LP3985 is stable with a small 1µF ±30% ceramic or high-quality tantalum output capacitor. The micro SMD requires the smallest possible PC board area - the total application circuit area can be less than 2.0mm x 2.5mm, a fraction of a 1206 case size.
The LP3985's performance is optimized for battery powered systems to deliver ultra low noise, extremely low dropout voltage and low quiescent current. Regulator ground current increases only slightly in dropout, further prolonging the battery life.
An optional external bypass capacitor reduces the output noise without slowing down the load transient response. Fast startup time is achieved by utilizing an internal power-on circuit that actively pre-charges the bypass capacitor.
Power supply rejection is better than 50dB at low frequencies and starts to roll off at 1kHz. High power supply rejection is maintained down to low input voltage levels common to battery operated circuits.
The device is ideal for mobile phone and similar battery powered wireless applications. It provides up to 150mA, from a 2.5V to 6V input. The LP3985 consumes less than 1.5µA in disable mode and has fast turn-on time less than 200µs.
The LP3985 is available in a 5-bump thin micro SMD and a 5-pin SOT-23 package. Performance is specified for −40°C to +125°C temperature range and is available in 2.5V, 2.6V, 2.7V, 2.8V, 2.85V, 2.9V, 3.0V. 3.1V, 3.2V, 3.3V, 4.7V, 4.75V, 4.8V and 5.0V output voltages. For other output voltage options between 2.5V to 5.0V or for a dual LP3985, please contact a Texas Instruments sales office.
2.5 to 6.0V input range 150mA guaranteed output 50dB PSRR at 1kHz @ VIN = VOUT + 0.2V ≤1.5µA quiescent current when shut down Fast Turn-On time: 200µs (typ.) 100mV maximum dropout with 150mA load 30µVrms output noise (typ.) over 10Hz to 100kHz −40 to +125°C junction temperature range for operation 2.5V, 2.6V, 2.7V, 2.8V, 2.85V, 2.9V, 3.0V, 3.1V, 3.2V, 3.3V, 4.7V, 4.75V, 4.8V and 5.0V outputs standard