AMR28XXD SERIES

(28V Input, Dual Output)

5

2016-06-29

Notes to Specifications

1. Parameter guaranteed by line and load regulation tests.

2. Up to 90 percent of full power is available from either output provided the total output does not exceed 30 watts.

3. Bandwidth guaranteed by design, Tested for 20 Hz to 2 MHz.

5. 3 watt load on output under test. 3 watt to 27 watt load change on other output.

6. Capacitive load may be any value from 0 to the maximum limit without compromising DC performance. A capacitive load in excess

of the maximum limit will not disturb loop stability but may interfere with the operation of the load fault detection circuitry, appearing

as a short circuit during turn-on.

7. Parameter shall be tested as part of design characterization and after design or process changes, Parameters shall be guaranteed

to the limit specified in Electrical Specifications

8. Load step transition time between 2 and 10 microseconds.

9. Recovery time is measured from initiation of the transient to where Vout has returned to within ±1% of Vout at 50% load.

10. Input step transient time between 2 and 10 microseconds.

11. Turn-on delay time measurement is for either a step application of power at the input or the removal of a ground signal from the

inhibit pin while power is applied to the input.

Block Diagram

8

7

+Output

Output

Return

Pulse Width

Modulator

Primary

Housekeeping

Supply

EMI

Filter

Under-Voltage

Detector

1

3

10

2

+Input

Enable

Sync

Input

Input

Return

Error

Amp &

Ref

FB

CS

Drive

6

-Output

5

Case

Application Information

Inhibit Function (Enable)

Connecting the inhibit input to input common will cause the

converter to shut down. It is recommended that the inhibit

pin be driven by an open collector device capable of sinking

at least 400 µA of current. The open circuit voltage of the

EMI Filter

An optional EMI filter is available (AFH461) that will reduce

the input ripple current to levels below the limits imposed by

MIL-STD-461 CE03. 

Device Synchronization

When multiple DC-DC converters are utilized in a

single system, significant low frequency noise may

be generated due to a small difference in the switching

frequency of the converters (beat frequency noise).

Because of the low frequency nature of this noise

(typically less than 10 kHz), it is difficult to filter out

and may interfere with proper operation of sensitive

systems (communication, radar or telemetry). IR

HiRel provides synchronization of multiple AMR

type converters to match switching frequency of the

converter to the frequency of the system clock, thus

eliminating this type of noise.