The Tektronix PS5004 is a programmable precision power supply plug-in for the TM5000 system. It operates only in TM5003 or TM5006 mainframes. The maximum output power does not change when operated in the TM5006 high power compartment.

Tektronix PS5004
programmable precision power supply
Tektronix PS5004

Produced from 1984 to 1995

Manuals
(All manuals in PDF format unless noted otherwise)

Specifications

The output range is 0 to +20.0000 V, settable in 500 μV steps. Output current can be adjusted from 5 to 300 mA in 5 mA steps. A 4⅔ digital meter can be selected to monitor the actual output voltage, output current, or current limit setting. Results are displayed on the front panel LED display, and can be read through the GPIB.

The power supply has a basic DC accuracy of 0.01%, better than many 4½ digit DMMs. It can be used as a programmable calibration source for many 3½ digit meter applications. To maintain the precision at the point of use, the outputs have remote sensing inputs. Internal resistors clamp the sensing inputs to the output terminals, allowing the supply to be used with the sensing terminals left open.

Internals

The power supply used a unique method of programming the voltage. At the time the instrument was designed, 16 bit DACs using conventional R-2R ladder networks were rare and extremely expensive – more than the target manufacturing cost for the entire instrument. The DAC uses a gated charge transfer technique, and is implemented from discrete components. The output of a negative precision current source is steered either into the summing node of a current to voltage converter, or pulled up to a supply voltage. The switch is driven by a digital logic which forms a constant period, variable pulse width waveform. A digital counter determines the pulse width, with each count representing the weight of a least significant bit. An integrator, followed by a four pole quasi-elliptical filter tuned to the pulse frequency reduce the ripple to less than 100 μV.

Firmware

Pictures

Components

Some Parts Used in the PS5004

Part Part Number(s) Class Description Used in
Motorola 6800 156-0426-00 156-2413-00 156-5472-01 Monolithic integrated circuit 8-bit microprocessor 021-0206-00 021-0374-00 067-0902-00 067-1137-99 222 222A 222PS 2424L 2445 2465 2467 4051 7250 7912 7912AD 7A16P 7A29P 7B81P 7B90P 833 834 835 836 CG5001 CG551AP CG5010 CG5011 DF1 DF2 DM5010 FG5010 MI5010 SI5010 PS5004 PS5010 SG5010 Keithley 181 Keithley 182 Keithley 175 Keithley 175A Keithley 191 Keithley 192 Keithley 195 Keithley 195A Keithley 197 Keithley 220 Keithley 224 Keithley 230 Keithley 263 Keithley 485 Keithley 580 Keithley 617
TMS9914 156-1444-00 156-1444-01 Monolithic integrated circuit GPIB controller 11301 11301A 11302 11302A 2221 2230 2424L 2440 4052A 4054A 021-0374-00 067-1137-99 AM700 DC5009 DC5010 DM5010 DM5110 DM5120 DM5520 FG5010 MI5010 SG5010 SG5030 SI5010 PS5004 PS5010 Keithley 182 Keithley 193A Keithley 195 Keithley 195A Keithley 196 Keithley 197 Keithley 199 Keithley 220 Keithley 224 Keithley 230 Keithley 263 Keithley 617