Texas Instruments LP3985 Micropower 150mA Low-Noise Ultra Low-Dropout CMOS Voltage Regulator is designed for portable and wireless applications with demanding performance and space requirements. LP3985's performance is optimized for battery-powered systems to deliver ultra-low noise, extremely low dropout voltage, and low quiescent current. LP3985 offers up to 150mA guaranteed output, a 2.5V to 6V input range, fast turn-on timeless than 200μs, and consumes less than 1.5μA in disable mode. Performance is specified for a temperature range of −40°C to +125°C with 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. LP3985 is stable with a small 1μF ±30% ceramic or high-quality tantalum output capacitor. Regulator ground current increases only slightly in dropout to further prolong the battery life. An optional external bypass capacitor reduces the output noise without slowing down the load transient response. An internal power-on circuit actively pre-charges the bypass capacitor to achieve a fast turn-on time. 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. Available in a 5-bump thin micro SMD and a 5-pin SOT-23 package, the device requires the smallest possible PC board area with a total application circuit area that can be less than 2.0mm x 2.5mm, a fraction of a 1206 case size. LP3985 is ideal for mobile phones and similar battery-powered wireless applications including CDMA cellular handsets, wideband CDMA cellular handsets, GSM cellular handsets, and portable information appliances.
