DATA SHEET
LM27761 Low-Noise, Regulated, Switched-Capacitor Voltage Inverter
1 Features
- Inverts and Regulates the Input Supply Voltage
- Low Output Ripple
- Shutdown Lowers Quiescent Current to 7 µA (Typical)
- Up to 250-mA Output Current
- 2.5-Ω Inverter Output Impedance, VIN = 5 V
- ±4% Regulation at Peak Load
- 370-µA Quiescent Current
- 2-MHz (Typical) Low-Noise Fixed-Frequency Operation
- 35-dB (Typical) LDO PSRR at 2 MHz
With 80-mA Load Current - 30-mV LDO Dropout Voltage at 100 mA,
VOUT = –5 V - Current Limit and Thermal Protection
- Create a Custom Design Using the LM27761 With the WEBENCH® Power Designer
2 Applications
- Operational Amplifier Power
- Wireless Communication Systems
- Cellular-Phone Power-Amplifier Biasing
- Interface Power Supplies
- Handheld Instrumentation
- Hi-Fi Headphone Amplifiers
- Powering Data Converters
3 Description
The LM27761 low-noise regulated switched-capacitor voltage inverter delivers a very low-noise adjustable output for an input voltage in the range of 2.7 V to 5.5 V. Four low-cost capacitors are used in the application solution to provide up to 250 mA of output current. The regulated output for the device is adjustable between −1.5 V and −5 V. The LM27761 operates at 2-MHz (typical) switching frequency to reduce output resistance and voltage ripple. With an operating current of only 370 µA (charge-pump power efficiency greater than 80% with most loads) and 7-µA typical shutdown current, the LM27761 provides ideal performance when driving power amplifiers, DAC bias rails, and other high-current, low-noise voltage applications.
Device Images
Typical Application
