Shared Projects

Tektronix 1240 / 1241 CR2032 Battery Retrofit

TMT - 3M to Positronic Warping Harness Strain Gauge Adapter Board - Version 1.0.

First iteration of RFID evaluation module

Board to blow up resistors using wave form generator and simultaneously watch using oscilloscope

A FeatherWing to adapt the SparkFun Sound Detector to a Feather form-factor. See GitHub for BOM and more information.

NOTE: There is a new version of this adapter.

This board is a small and cheap pogo pin programming solution designed in my case for a Lattice HW-USBN-2A (2.54mm pitch pin header) and the gMUX JTAG connector on a logic board of a MacBook Pro 15" early 2011 (pogo pins). This connector is not soldered on the logic board, thus I will use the pogo pins.

The pogo pins are TH pads with 1.2mm pitch and hole size of .75mm diameter. I will use this pogo pin: P50-J1 or P50-B1. Both have a .68mm diameter. I will solder the ground pin slightly lower so it is the first to make contact when the pogo pins are pressed on the pads.

This PCB has been tested and it works, but I designed a newer better version because the “public domain” text is not readable I added a capacitor between TCK and GND. For the PCB version v0 I soldered the capacitor between the pins of the header.

The hole in the top left is thought to insert a lanyard.

Feel free to do with it whatever you want (public domain)

BOM

This is the EasyFlash v1 for the Commodore 64 and MEGA65

Just the module, 3.3V buck regulator, and the transistors for switching into bootloader mode using DTR and RTS from an external USB-to-serial converter such as a CP2102.

Partlist

Exported from breakout.sch at 2/1/2020 5:14 PM

EAGLE Version 7.4.0 Copyright © 1988-2015 CadSoft

Assembly variant:

Part     Value              Device              Package         Library                Sheet
C1       22u                C_EU_0805           0805            CRAIG_SMD_PACKS_000004 1
C2       0.1u               C_EU_0603           0603            CRAIG_SMD_PACKS_000004 1
C3       0.1u               C_EU_0603           0603            CRAIG_SMD_PACKS_000004 1
C4       0.1u               C_EU_0603           0603            CRAIG_SMD_PACKS_000004 1
C5       10u                C_EU_0805           0805            CRAIG_SMD_PACKS_000004 1
D1       5.5V Zener         DIODE/SHOTKY_SOD323 SOD323          CRAIG_SMD_PACKS_000004 1
JP1                         PINHD-2X10          2X10            pinhead                1
JP2                         PINHD-2X10          2X10            pinhead                1
L1                          INDUCTOR_1008       1008            CRAIG_SMD_PACKS_000004 1
R1       10K                R_US_0603           0603            CRAIG_SMD_PACKS_000004 1
R2       10K                R_US_0603           0603            CRAIG_SMD_PACKS_000004 1
R3       10K                R_US_0603           0603            CRAIG_SMD_PACKS_000004 1
T1       SS8050-G           BC808-NPN-SOT23-BEC SOT23-BEC       transistor             1
T2       SS8050-G           BC808-NPN-SOT23-BEC SOT23-BEC       transistor             1
U1       ESP32_WROVER_V4    ESP32_WROVER_V4     ESP32_WROVER_V4 esp32_wrover_v4        1
U2       BUCK_SEMTECH_SC189 BUCK_SEMTECH_SC189  SOT23-5         CRAIG_SMD_PACKS_000004 1

USE ONLY with ASMB-MTB0-0A3A2 LED. Constructing the smart skeleton will require 1 order of 9 copies of this board. See github.com/jmpattillo for schematic and board files. The ASMB-MTB0-0A3A2 LED is no longer being manufactured. If you are unable to acquire this part, then use version 0.3 of this board, which is designed to work with LED part number ASMB-BTE1-0B332

Constructing the smart skeleton will require 1 order of 3 copies of this board. This board interfaces with an Adafruit Feather Huzzah ESP8266 microcontroller (adafruit product id 2821), and the adafruit TCA9548 breakout board (adafruit product id 2717). See github.com/jmpattillo/smart-skeleton for schematic and board files

Kay Tremolo

Yet another Arduino GPIB interface V0.1

Carrier board for Adafruit Trinket M0 as watchdog for EVNotiPi

Debug Stemma QT with BitMagic

Version 1.2 of the LiPo battery to 9V active pickup power supply.

Only changed the company info from v1.1.

Driver board for a Dual-Resonance Solid-State Musical Tesla Coil. This version is a mix of the V1 Version and the V2 Version.

This version uses the original UCC37322 drivers (only in the MSOP-PowerPAD footprint instead) and runs on +15V like the V1, but includes the Skip Pulse and thermal limiter input logic from the V2.

The general layout also conforms to the V2 format and is designed to be mounted upright like the V2 instead of upside-down like the V1.

Note: Change RV2 and/or R20 to adjust the SG3525 PLL circuit for your coil’s resonant frequency. With the values of 2K for RV2 and 1K for R20, as labeled, it works for a coil with an approximate resonant frequency of 200-250kHz. Changing them, for example, to 10K for RV2 and 6.8K for R20, it works for a coil that’s approximately 45-100kHz. The exact range is dependent on the dead-time setting, as it alters the frequency slightly, and by component tolerance and circuit parasitics. Refer to the SG3525 datasheet for the frequency equations. Note that FreqOut is 2x the resonant frequency due to the SG3525 dividing the frequency for the dual outputs. The Free-Running frequency of the PLL should be set to about 5% less than 2x the primary circuit resonant.

ERRATA: There is a logic error in the lockout circuit that causes a race-condition with the U9 flip-flop (74LVC1G74) between the fiber-optic edge detect signal on the set-input and the main fiber-optic signal on the clock pin. This can cause the system to never start and results in only a short burst of output at the beginning of each interrupter pulse, and it also prevents the skip-pulse mode from working at all.

To resolve, the fiber optic input signal needs to be removed from pin 1 of U9. And the skip-pulse signal on pin 2 needs to move to pin 1. And pin 2 needs to get tied to +5v. To do this, cut the trace leading into pin 1 of U9 (leaving the 90-degree junction intact where it runs under U4), and cut the trace leading into pin 2 of U9 between U9 and resistor R52. Solder a jumper between pin 1 of U9 and R52, on the end where the trace to pin 2 was cut (this takes care of moving the skip-pulse signal from pin 2 to pin 1). And solder a small jumper wire to pin 2 of U9 that runs to +5v. The closest and probably most convenient point for +5v is the far end of capacitor C40, which is the power decoupling capacitor for U9. This jumper can be quite tricky as it has to solder to a single pin on a TSSOP package (0.65mm pin-spacing).

This errata will be resolved in V3.1.