1 Features

• Eight analog outputs

– Eight monotonic DACs: 1.22mV resolution

– Automatically configured output ranges:

• Positive output voltage: 0V to 10V

• Negative output voltage: –10V to 0V

– High current drive capability

– High capacitive load tolerance

• Output on and off control switches

– Fast switching time

– Low resistance

• Multichannel ADC monitor

– Two high-voltage external inputs: 0V to 85V

– Two high-side current-sense amplifiers: up to

85V common mode range

– Local temperature sensor: ±2.5°C error

• Output sequence control for start-up and shutdown

events

• Internal 2.5V reference

• SPI and I2C interface: 1.65V to 3.6V operation

– SPI: 4-wire interface

– I2C: 16 target addresses

• Specified temperature range: –40°C to +125°C

• Operating temperature range –55°C to +150°C

2 Applications

• Radar

• Electronic warfare

• Software defined radio

• Seeker front end

3 Description

The AFE20408 is a highly integrated power-amplifier

(PA) monitor and control device capable of

temperature, current, and voltage supervision.

The AFE20408 bias controller is based around

eight digital-to-analog converters (DACs) with

programmable output ranges. The eight gate bias

outputs are switched on and off through dedicated

control pins. The gate bias switches are designed for

fast response and enable correct power sequencing

and protection of depletion-mode transistors, such as

GaAs and GaN.

The AFE20408 supervisor is based around an

accurate multichannel analog-to-digital converter

(ADC). The device integrates two high-voltage

inputs, two high-side current-sense amplifiers and an

accurate on-chip temperature sensor.

The function integration and wide operating

temperature range make the AFE20408 an excellent

choice as an all-in-one, bias control circuit for power

amplifiers. The flexible DAC output ranges and builtin

sequencing features let the device be used as

a biasing controller for a large variety of transistor

technologies, such as LDMOS, GaAs, and GaN.