AM80A-300L-120F18 Astec Power, AM80A-300L-120F18 Datasheet - Page 22

• Manufacturer Part Number: AM80A-300L-120F18
• Manufacturer: Astec Power

22
Design Considerations
Input Bulk Capacitors
Electrolytic bulk reservoir capacitors placed close to the
module input pins are recommended to ensure the module
is fed with a low source impedance. For the AM80A
Performance Series module typical values are 220µF/100V
for 48V modules and 220µF/450V for 300/320V modules.
Input Fusing
AMPSS modules do not have an in-line fuse fitted
internally. In order to comply with CSA, VDE and UL
safety regulations it is recommended that a fuse of the
following rating be fitted at the module's input.
Remote Loads
If the sensed load is some distance from the module, the
module's output voltage may rise sufficiently to trigger the
OVP protection circuit during a step load change due to
bus inductance. For this reason the OVP margin should be
increased in extreme cases. Fitting a decoupling capacitor
at the load can reduce this effect.
It should be noted that a distributed power solution, using
AMPSS
optimize transient response.
AMPSS
TM
300V/320V
modules placed close to their loads, will
Input
150V
V
48V
I
®
220µF
Reference Manual
+
Fuse Rating
10A / 250V
10A / 250V
10A / 250V
+I/P
-I/P
Thermal Data
Natural convection thermal impedance of the AM80A
package without a heatsink is approximately 4°C/W.
The below characteristic is for a standard horizontal fin
heatsink available from Astec (part number APA501-80-
002) with 11mm fins and 8mm pitch. The heatsink will
reduce module thermal impedance to 1°C /W with a forced
air flow of 250 LFM when mounted with a thermal pad
(ASTEC P/N APA502-80-001) between heatsink and
module.
Overtemperature Protection
If the module's baseplate temperature exceeds 110°C, the
module will latch OFF. To reset the module the input
supply or the enable pin of the module must be cycled off
and then on again, allowing a period of time for the module
to cool down.
Overtemperature shutdown can also be programmed to
occur at lower temperatures by using the TEMP MON
output to control the ENABLE pin.
7
6
1. 2
0. 8
0. 6
0. 4
0. 2
1
0
0
12
1
200
+SENSE
-SENSE
F o rced C o n vect i o n f o r A P A 501- 80- 002
+O/P
-O/P
400
at 200W O u t p u t
V ai r ( L F M )
600
Rev. 05 Mar 99
800
Load
0.1 µF
1000