GENERAL DESCRIPTION

The ADuM4470/ADuM4471/ADuM4472/ADuM4473/

ADuM44741 are quad-channel, digital isolators with a regu- lated dc-to-dc isolated power supply controller and an internal MOSFET driver. The dc-to-dc controller has an internal isolated

PWM feedback from the secondary side, based on the iCoupler?

chip scale transformer technology and complete loop compen-

sation. This eliminates the need to use an optocoupler for

feedback and compensates the loop for stability.

The ADuM447x isolators provide a more stable output voltage

and higher efficiency compared to unregulated isolated dc- to-dc power supplies. The fully integrated feedback and loop

compensation in a wide-body SOIC package provide a smaller

form factor and 8.3 mm creepage distance solution.

The regulated feedback provides a relatively flat efficiency curve

over the full output power range. The ADuM447x enable a dc-

to-dc converter with a 3.3 V to 24 V isolated output voltage

range from either a 5.0 V or a 3.3 V input voltage, with an

output power of up to 2.5 W. The ADuM447x isolators provide four independent isolation

channels in a variety of channel configurations and data rates.

(The x in ADuM447x throughout this data sheet stands for the

ADuM4470/ADuM4471/ADuM4472/ADuM4473/ADuM4474.)

FEATURES

Isolated PWM feedback with built in compensation

Primary side transformer driver for up to 2.5 W output

power with 5 V input voltage

Regulated adjustable output: 3.3 V to 24 V Up to 80 efficiency

Quad dc-to-25 Mbps (NRZ) signal isolation channels 200 kHz to 1 MHz adjustable oscillator

Soft start function at power-up

Pulse-by-pulse overcurrent protection

Thermal shutdown 5000 V rms isolation

High common-mode transient immunity: >25 kV/μs

20-lead SOIC package with 8.3 mm creepage High temperature operation: 105°C

APPLICATIONS

Power supply start-up bias and gate drives

Isolated sensor interfaces Process controls RS-232/RS-422/RS-485 transceivers