LTC1551L Datasheet | Linear Technology

LTC1550L/LTC1551L Low Noise, Switched Capacitor Regulated Voltage Inverters Features s s s s s s s s DESCRIPTIO s s Regulated Negative Voltage from a Single Positive Supply Low Output Ripple: Less Than 1m VP-P Typ High Charge Pump Frequency: 900k Hz Small Charge Pump Capacitors: 0.1µF Requires Only Four External Capacitors Fixed - 4.1V, - 2.5V, - 2V or Adjustable Output Shutdown Mode Drops Supply Current to <1µA High Output Current: Up to 20m A (Depending on VCC to VOUT Range) Output Regulation: 2.5% Over Line, Load and Temperature Available in 8-Lead MSOP, 8-Lead Narrow SO and 16-Lead Narrow SSOP The LTC®1550L/LTC1551L are switched capacitor charge pump voltage inverters which include internal linear postregulators to minimize output ripple. The LTC1550L fixed output voltage versions include - 4.1V, - 2.5V and - 2V with ripple voltages typically below 1m VP-P. The LTC1550L is also available in an adjustable output voltage version. The LTC1550L/LTC1551L are ideal for use as bias voltage generators for Ga As transmitter FETs in portable RF and cellular telephone applications. The LTC1550L/LTC1551L operate from single 2.7V to 5.5V supplies and draw typical quiescent currents of 3.5m A with a 5V supply. Each device includes a TTL patible Shutdown pin which drops supply current to 0.2µA typically. The LTC1550L Shutdown pin is active low (SHDN), while the LTC1551L Shutdown pin is active high (SHDN). Only four external ponents are required: an input bypass capacitor, two 0.1µF charge pump capacitors and a filter capacitor at the linear regulator output. The adjustable LTC1550L/LTC1551L require two additional resistors to set the output voltage. The LTC1550L/LTC1551L will supply up to 20m A (depending on VCC to VOUT range), while maintaining guaranteed output regulation of ± 2.5%. Both fixed voltage and adjustable LTC1550L/LTC1551L are available in 8-lead MSOP and SO plastic packages: the adjustable LTC1550L is also available in a 16-pin SSOP with the REG pin. VOUT...