19-0238; Rev 2; 4/96
Low-Noise, Regulated, Negative Charge-Pump Power Supplies for GaAsFET Bias
_______________General Description
The MAX850–MAX853 low-noise, inverting, chargepump power supplies are ideal for biasing GaAsFETs in cellular telephone transmitter amplifiers.
The MAX850–MAX852 offer both preset (-4.
1V) and adjustable (-0.
5V to -9.
0V) output voltages.
The MAX853 uses an external positive control voltage to set the negative output voltage.
Input voltage range for all four devices is 4.
5V to 10V.
Output current is 5mA.
An internal linear
regulator reduces the output voltage ripple to 2mVp-p.
With a well-filtered control voltage (VCTRL), the MAX853 achieves typical output ripple o...