MAX881REUB+ (MAXIM INTEGRATED PRODUCTS)

The MAX881REUB+ is a low noise bias supply with power-OK for GaAsFET power amplifiers in 10 pin µMAX package. This inverting power supply is a charge pump inverter followed by a negative linear regulator. The input voltage range is 2.5V to 5.5V. The output is preset at -2V or can be set using two resistors to any voltage from -0.5V to (-VIN + 0.6V). It can deliver up to 4mA. The internal linear regulator also filters the output to 1mVp-p ripple and noise. The MAX881R includes power-OK (active-low POK) output that signals when negative voltage is within 7.5% of its set point. It protects GaAsFET by not allowing power to be applied to GaAsFET's drain until it is properly biased. The signal can be routed either to a microcontroller or directly to aswitch at the GaAsFET drain.