Connectorboard; Power ~3Upply - HP 200 Series Hardware Support Document

Functional Description
21
1/0 Connectorboard
The
110
connectorboard contains six accessory slots for adding RAM cards, a DMA controller card,
a floating-point math card or for interface cards used for connecting peripherals.
Each two connectors are protected by a fuse on the
+
5V line. These fuses are mounted on the
connectorboard, along with a fuse protecting the processor board.
The power supply post-regulators are mounted on the
110
connectorboard.
Power Supply
The function of the power supply is to change line voltage into filtered, regulated dc levels of
+
5 V,
+
12 Vand -- 12 V. Overvoltage protection is provided on the
+
5 V line. Overcurrent protection is
provided on the
+
12 and -12 V lines.
The power supply consists of these assemblies:
• ac input hardware
• power supply module
• post-regulators
• fan
Ac power enters
throu~3h
the ac socket on the rear panel. The socket contains a fuse and a voltage
select switch which selects between 90-125 and 198-250 Vac. The ac passes to the power supply
module, which rectifies it to de. The power supply module is a sWitching supply, and produces
regulated
+
5 Vdc and unregulated
+
14 and -14 Vde. Post-regulators physically mounted on the
110
connectorboard convert the
+
14 Vdc to
+
12 Vdc and the -14 Vdc to -12Vdc.
The fan operates on the
+
5 and -- 14 V lines.
Figure 5-1 is a diagram of the distribution paths for ac and dc power.