DEC power distribution connectors

From Computer History Wiki
Jump to: navigation, search

Many DEC PDP-11 backplanes use a common system of connectors to the power harness which leads from the power supply.

They were connected to the harness (which usually ended in a power distribution panel) using multi-pin AMP MATE-N-LOK connectors: the connectors on the panel used male shells (housings) with female sockets (i.e. female pins); all the cables from the backplanes had female shells. with male pins.

Generally the DEC standard power wire colour coding was used.

Pinouts

Some early machines (e.g. the early versions of the PDP-11/05) used 9-pin connectors; all the later machines and mounting boxes used pairs of 6-pin and 15-pin connectors.

The pinout of the 9-pin connector is:

Pin Signal
1 DCLO
2 ACLO
3 -15V
4 Ground
5 Ground
6 Ground
7 LTC
8 +15V
9 +5V

Pin 1 is the pin nearest the ridge on the side of the shell; there are two corner keys on the 7-9 side of the shell, on the inside.

The pinouts of the 6-pin and 15-pin connector are:

Pin Signal
1 Ground
2 LTC
3 DCLO
4 ACLO
5 Unused
6 Unused

Again, pin 1 is the pin nearest the ridge on the side of the shell, and there are two corner keys on the 4-6 side of the shell, on the inside.

Pin Signal
1 +5V
2 +15V
3 +20V or +15VC
4 +5V
5 Ground
6 +15B (Battery backup)
7 Ground
8 Ground
9 Ground
10 Unused
11 Ground
12 +5B (Battery backup)
13 -15V
14 -5V
15 -15B (Battery backup)

Once again, pin 1 is the pin nearest the ridge on the side of the shell, and there are two corner keys on the 13-15 side of the shell, on the inside.

Not all supplies/harnesses provided the battery backup voltages.

Note: On the H777 Power Supply, versions UA, UB, used with the PDP-11/24 in the BA11-L mounting box, pins 6 and 15 are +12V/-12V, for use with the MS11-M MOS memory; pin 3 is +15C. (This unit did not use a harness, the connectors are on the power supply casing.)

Connectors

The female sockets (female pins) are AMP part number 60619-1; the male pins are 60620-1. (There are a large number of different pin options: 30-22, 24-18, and 20-14 gauge; tin and gold plated; and brass and phosphor-bronze material. The part numbers given are for tinned brass, 20-14 gauge.)

The AMP part numbers for the shells (AMP calls the female housings 'caps', and the male housings 'plugs') are below:

Pin count Male shell Female shell
6 1-480273-0 1-480276-0
9 1-480274-0 1-480277-0
15 1-480323-0 1-480324-0

AMP has been bought by TE Connectivity, but these MATE-N-LOK connectors are still in production, and available from the usual suppliers.

External links