Month: December 2024

Final Update for the UCA: Power Supply Overhaul

Designing a stable, adjustable and fail-safe power supply for the Universal Chip Analyzer has been one of the most challenging aspects of this project and I was quite reluctant to touch that part of the schematics. For years, the DC-DC power supply stage on the UCA Interface Board relied on Texas Instruments’ PTH08080W module, mounted upside down. While this module is excellent and performs reliably, it has two significant drawbacks.

First, it’s expensive, costing around $8–$9 per unit. Additionally, as a non-standard through-hole component, it complicates assembly and increases costs when using a reflow machine.

More importantly, the PTH08080W module needed to be replaced to implement a highly requested feature from beta testers. Previously, a 9V external power supply was mandatory in addition to the 5V provided by the USB-C to power the UCA Interface Board. That external power supply powered the DC-DC converter, which delivered an adjustable output voltage ranging from 2.8V to 5.5V at up to 2A. However, in some cases (such as testing 5V-only CPUs that consume less than 300mA), the voltage provided by USB-C alone could be strong enough. Beta testers requested an alternative power option to use only USB-C power when it’s possible, and this final revision delivers on that request.

The PTH08080W module has been replaced with a discrete DC-DC converter, complemented by additional circuitry for digital control of the voltage output. An ideal diode controller has also been integrated to manage the USB-C 5V input, ensuring seamless switching and protection in the event of a failure.

The Universal Chip Analyzer now features two automatically selected power modes:

    • USB-C Only (No External Power)
      In this mode, the UCA can test 5V chips that draw less than 300mA. This includes, for example, all DIP40 ICs. Overcurrent and short-circuit protections are still in place, but the UCA will only allow this mode for compatible adapters. This setup is perfect for quick, portable testing in the field using a USB battery pack.

    • USB-C with 9V External Power
      This fully featured mode supports all UCA functionalities, including the ability to test a wide range of components, from early DRAM to late 5×86 chips. Adjustable voltages (e.g., 3.3V, 3.45V) are supported, with high current capability up to 2A. This mode is ideal for advanced bench analysis and testing of more demanding components.

With this final challenge resolved, I’ll be updating the UCA website and opening preorders in two weeks.

Thank you all for your patience and support!

 

Major Upgrade for the final DIP40 Adapter!

The Universal Chip Analyzer (UCA) beta testing is entering its final phase! Thanks to the valuable feedback from talented professionals and passionate retro enthusiasts, two critical improvements were identified and addressed before the official release. The first improvement concerns the Interface Board, and a detailed update is coming soon. The second key enhancement involves the DIP40 Adapter, which initially required additional top adapters to test common CPUs like the Zilog Z80, Motorola 6800, and MOS 6502.

These extra adapters were necessary because the power and ground pin configurations of these processors differ from those of Intel’s 8085/86/88, for which the original DIP40 adapter was designed. Switching VCC and GND to other pins is technically not very complex, but it’s much more difficult to keep these pins simultaneously usable by high-frequency signals. The transistors required to switch power lines add various parasitic noise to the pins, even when they’re switched off.

I’m happy to announce that the final DIP40 Adapter is now able to test the most common DIP40 CPUs from the 70s and 80s out of the box, without the need for any additional adapters! Here is a comparison of the old DIP40 adapter with some of its various top adapters, versus the newer “all integrated” one:

The DIP40 Adapter has a 4-way dip switch to select the CPU under test between the following:

    • Intel 8086/8088
    • Intel 8085
    • Zilog Z80
    • National Semiconductor NSC800
    • MCS-48 (80C48)
    • MCS-51 (8051)
    • RCA CDP1802 (COSMAC)
    • Intel 8087 (Work in progress)
    • Motorola 6800
    • Motorola 6801
    • Motorola 6802
    • Motorola 6809
    • MOS 6502
    • MOS 6510 (or MOS6509, still TBD, would like your opinion!)

All these CPUs are now supported by the DIP40 Adapter directly! This should cover 95% of the most common CPUs that came in DIP40. What about more obscure ones? If you zoom in on the picture above, you can see that two positions of the configuration switch are marked “CUSTOM #1” and “CUSTOM #2”. Users will be able to upload any other firmware to these two slots. For example, CPUs like the Motorola 6809E or the Ricoh 2A03 can be added in the custom slots when they become available. Basically, any CPU with VCC on pins 5, 6, 7, 8, 11, and/or 40, and GND on pins 1, 20, 21, and/or 29 can be supported. Some niche CPUs like the Signetics 2650 or the Intersil 6100 (which have vastly different pinouts compared to all other CPUs) will still need a custom adapter, but the new DIP40 Adapter alone should be enough for almost everyone out of the box, from pinball enthusiasts to retro researchers.