A5 Power Supply Assembly Description - Agilent Technologies PSA Series Service Manual

Troubleshooting the Processor, Power Supply, and Display

A5 Power Supply Assembly Description

A5 Power Supply Assembly Description
Purpose. The A5 Power Supply assembly is a switching power supply
that operates at a switching frequency of 121.95 kHz. The power supply
automatically senses the input power and selects between two voltage
ranges, 90 to 132 VAC or 195 to 250 VAC.
A low TTL level on the PS_off_L line turns off the power supply and
places it in standby mode. In standby mode, the front panel standby
LED is powered on by the P15SBY line from the power supply.When the
power supply is on, the "power on" front-panel LED is powered by the
5.2 V supply.
The power supply plugs directly into the motherboard. The power
supply output voltages are: +5.2 V, −5.2 V, +9 V, +15 V, −15 V, +32 V,
VCC (5.2 V for processor) and VDL (3.3 V to processor).
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