Anritsu 37 D Series, Maintenance Manual

Page: 60 / 190

Power Supply Module The Power Supply Module is a single self contained assembly mounted
on the left side wall of the chassis, behind the LCD. This module pro-
vides:
q Unreg5, +9,
±
18, and
±
27 Vdc supply voltages to the
other assemblies of the 37XXXD
q Thermal and over-current shutdown protection circuitry
q Sensing and input power regulation for operation with
85 to 264 VAC, 48 to 63 Hz, universal AC line input power
q Internal fan cooling (for power supply module)
q Supply voltages distribution
Table 3-1 identifies all 37XXXD DC power supply voltages and lists
their usage by the various PCB assemblies. Unless otherwise indi-
cated, supply voltages are regulated on the assembly using them. The
analog and digital power supply grounds are isolated.
NOTE
All power supply voltages listed in Table 3-1 can be accessed
via the A/D bus for measurement by the the A/D converter
circuitry (for example, DVM) located on the A5 A/D PCB as-
sembly.
MAIN CHASSIS ASSEMBLIES THEORY OF OPERATION
3-24 37XXXD MM
Voltage Assemblies Where Used
+5V A1, A2, A3, A4, A5, A6, A7, A9, A13, A14, A15, A16, A18,
A19/A20 (P.O. Front Panel), A21A1/A21A2 (P.O. Source Mod-
ule), A24, External Keyboard
+9V A1, A2, A7, A8
+18V A1, A2, A3, A4, A5, A6, A7, A8, A13
-18V A1, A2, A3, A4, A5, A6, A7, A8, A13
+27V A1, A2, A5, A7
-27V A5, A18
The following supply voltages are derived from the
±
18 Vdc supply voltages
on the A13 I/O #1 PCB:
+12V A9, A15
-12V A9, A15
Table 3-1.
37XXXD Power Supply Voltages and Usages