AMF2800D_15 Datasheet, PDF (5/7 Pages) International Rectifier – HYBRID - HIGH RELIABILITY RADIATION TOLERANT DC-DC CONVERTER

AMF28XXD Series
(28V Input, Dual Output)
Notes to Specifications
1. Applicable to positive and negative outputs.
2. Maximum combined output is 12W. 10.8W (max.) is available from either output (90%).
3. Load current split equally between +VOUT and –VOUT.
4. 1.2W load on output under test, 1.2W to 10.8W load change on other output.
5. Capacitive value 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.
6. Parameter shall be tested as part of design characterization and after design or process changes. Thereafter,
parameters shall be guaranteed to the limit specified.
7. Load step transition time between 2.0µs and 10µs.
8. Recovery time is measured from initiation of the transient to where VOUT has returned to within ±1% of VOUT at
50% load.
9. Input step transient time between 1.0µs and 10µs.
10. 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
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+Input
1
Enable
6
Case
2
Sync
Input
EMI
Filter
Primary
Housekeeping
Supply
Drive
Pulse Width
Modulator ^FB
CS
Error
Amp &
Ref
3
+Output
4 ^Output
Return
5
- Output
Input
Return
7
Application Information
Inhibit Function (Enable)
Connecting the enable input (Pin 1) to input common
(Pin 7) will cause the converter to shut down. It is
recommended that the enable pin be driven by an
open collector device capable of sinking at least 400
µA of current. If the user chooses not to use the inhibit
function, it may be left open and the converter will
function normally. Because it is internally pulled up,
the open circuit voltage of the inhibit input is 10 +1.0VDC.
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.
www.irf.com
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 10KHz), it is
difficult to filter out and may interfere with proper
operation of sensitive systems (communication,
radar or telemetry). International Rectifier provides
synchronization of multiple AMF type converters to
match switching frequency of the converter to the
frequency of the system clock, thus eliminating this
type of noise.
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