SCE4800

HV Power Supply Model 4800

This dual output, full military, high voltage supply powered a Direct View Storage CRT in an aircraft environment. The design of the 10KV/750Amp section is conventional.

Besides the normal requirements on the -2KV output, the spec also required that upon turn-on the focus voltage rise at a specified ramp rate and that during very severe load transients - which are characteristic of a DVST, during erase/refresh - the focus voltage change by less than 1V.

We achieved ramp control using a digital technique. The load transient requirement was met with an active cancellation scheme which applied the correction voltage directly to the supply output, thus circumventing unavoidable delays through the high voltage stage.

SPECIFICATIONS

Electrical

Input:

Voltage 19 to 29VDC
Power 27W, max.

Output:
Anode:

Voltage 10KV fixed output (± 2%)
Current 750µA max
Regulation +3% load, +3% line
Ripple 0.2% (20V) p-p, maximum
Test Output -5V "2KV good" output indicator

Focus:

Voltage -2000V, fixed output (± 2%)
Current 600µA
Regulation ± 0.05% line, ± 0.1% load. Output will not vary by more than 1V under any input or output conditions
Ripple 1V p-p, maximum
Test Output -5V "2KV good" output indicator

Protection Circuits

Output Overload Supply protected against excessive load on output
Short Circuit Protected against output shorts for an indefinate period
Reverse Polarity Inputs protected against reverse polarity

Environmental

Operating Temperature -55ºC to + 85ºC
Humidity To 100% (fully sealed construction)
25G's, 50G Crash safety
Altitude 30,000 feet

Construction: Sealed steel case with internal aluminum sub plate

Weight 5.0 lbs., max.
Marking Photo anodized aluminum label
Potting HV section is vacuum filled with silicone