The PCB in this repo is a quick and dirty clone of the HP 01650-63203 termination adapter, used for direct connection of a 40-pin pod cable to a dedicated test port, providing a passive termination network to minimise loading on the device under test. By adding a cheap set of hookup leads and minigrabbers, it can also serve as a DIY replacement for the probe pods that are so frequently missing from analzyers that crop up on the used market.

Per HP application note AP1244 "Minimizing Intrusion Effects when Probing with a Logic Analyzer", each probe must be terminated with a series RC network as below (from Figure 1):

HP sold arrays of this termination network (1810-1278 for 9 networks in a DIP package, 1810-1588 for 5 networks in a SIP package). Naturally these are either NLA or not available for purchase by mere mortals, but it's easy enough to implement it in discrete components.

The logic analyzer supplies +5V at 600mA to each pod connector on pins 1 and 39 of the 40-pin connector. The 01650-63203 termination adatper brings this supply out to pin 1 of the 20-pin connector. Per HP's documentation, this is intended solely for powering active probe hardware, and must be a no-connect on the device under test.

For safety, on this adapter, the +5V supply is broken by a solder jumper that must be closed in order to supply +5V to the 20 pin connector.

Each adapter requires the following

Conveniently, JLCPCB's minimum order quantity of 5 is exactly the number of pods required for my 1652B analyzer. I ordered a set of 5 boards with SMD components preassembled for approximately 25 USD.

The original 01650-63203 adapters had an exposed section of flexible PCB, terminated in a 20 pin IDC receptacle, designed to directly connect to a board-mounted header on the DUT. This adapter substitutes this with a header - a short length of ribbon cable can be used to connect to the DUT, or standard Dupont leads can be connected to the pins for individual probes.

This project is presented on an as-is, 'works for me' basis. You are welcome to build it, use it, adapt it to your own purposes, but all at your own risk.