MAX840 Datasheet (Maxim) - Low-Noise / Regulated / -2V GaAsFET Bias

MAX840, Low-Noise / Regulated / -2V GaAsFET Bias

The MAX840/MAX843/MAX844 low-noise, inverting charge-pump power supplies are ideal for biasing GaAsFETs in cellular telephone transmitter amplifiers.

They operate with inputs down to 2.5V.

The MAX840 offers both a -2V preset output and a -0.5V to -9.4V adjustable output.

The MAX843/MAX844 use an ext

MAX840 Features

* o Fixed -2V or Adjustable -0.5V to -9.4V Output at 4mA (MAX840) o 2.5V to 10V Input Voltage Range o Operate with Small Capacitors (as low as 0.22µF) o 1mVp-p Output Voltage Ripple o Charge-Pump Switching Frequency: 100kHz in Normal Operation 20kHz in Shutdown Mode (MAX844) o 1µA Max Logic-Level Shut