HP MAY21J8412 7.2.1 USDT Power Distribution, Table, USDT Power Supply Specifications

Power and Signal Distribution

7.2.1 USDT Power Distribution

The USDT form factor uses an external (“brick”) supply that connects to the chassis through a three-conductor cable (Figure 7-1). The USDT power supply is available in 135-watt and180-watt versions. All voltages required by the processing circuits, peripherals, and storage devices are produced on the system board from the 19.5 VDC produced by the external power supply assembly. The external power supply always produces 19.5 VDC as long as it is connected to an active AC outlet.

	Front Bezel			USDT Chassis
		Power Button					System Board
					Power Control Logic,
		Power On
					Voltage Regulators
			+19.5							Rtn	Pwr rating
						VDC					& ID
								External
90 - 264 VAC						Power Supply
									Unit

Figure 7-1. USDT Power Distribution, Block Diagram

Table 7-1 lists the specifications of the external supply.

Table 7-1.

USDT Power Supply Specifications

Parameter	135-watt supply	180-watt supply
Input Line Voltage Range	90–265 VAC	90–265 VAC
Line Frequency	47–63 Hz	47-63 Hz
Input Current, Maximum load @ 90 VAC	2.4 A	2.9 A
Output Voltage	19.5 VDC	19.5 VDC
Output Current, nominal load	3.5 A	4.6 A
Output Current, maximum load	6.9 A	9.2 A
Output Current, peak load (300 ms max) [1]	9.0 A	11 A

NOTES:

Total continuous power should not exceed power supply rating (i.e., 135 or180 watts).

[1] Using 100 VAC input. The output voltage is allowed to drop to a minimum of 15 VDC during the transient period.

7-2 www.hp.com Technical Reference Guide