LTC1550

Supply Voltage .............................................................. 7V
Output Voltage .................................. 0.3V to (VCC  14V)
Total Voltage, VCC to CPOUT ...................................... 14V
Input Voltage (SHDN Pin) ..............  0.3V to (VCC + 0.3V)
Input Voltage (REG Pin)................................  0.3V to 12V
Output Short-Circuit Duration ................................. 30 sec
Commercial Temperature Range ................. 0°C to 70°C
Extended Commercial Operating
Temperature Range (Note 3) .................  40°C to 85°C
Industrial Temperature Range ................  40°C to 85°C
Storage Temperature Range ................  65°C to 150°C
Lead Temperature (Soldering, 10 sec).................... 300°C


Description

The LTC®1550/LTC1551 are switched capacitor charge pump voltage inverters which include internal linear postregulators to minimize output ripple. Output voltages are fixed at  4.1V, with ripple voltages typically below 1mVP-P. The LTC1550 is also available in an adjustable output voltage version. The LTC1550/LTC1551 are ideal for use as bias voltage generators for GaAs transmitter FETs in portable RF and cellular telephone applications. 

The devices operate from single 4.5V to 6.5V supplies and draw typical quiescent currents of 4.25mA with a 5V supply. Each device includes a TTL compatible Shutdown pin which drops supply current to 0.2mA typically. The LTC1550 Shutdown pin is active low (SHDN), while the LTC1551 Shutdown pin is active high (SHDN). Only four external components are required: an input bypass capacitor, two 0.1mF charge pump capacitors and a filter capacitor at the linear regulator output. 

The adjustable LTC1550 requires two additional resistors to set the output voltage. The devices will supply up to 10mA output current with a 5V supply, while maintaining guaranteed output regulation of ±5%. The fixed voltage LTC1550/LTC1551 are available in S0-8 plastic packages. The adjustable LTC1550 is available in a 16-pin SSOP.