The MiniProg1 I have intermediately fails to program my PSoC. The MiniProg is able to program certain devices but fails for other devices in same family.
Response:MiniProg1 devices from 2008 and earlier have a hardware bug. For these MiniProg units the timing of the programming signal is sometimes outside of the Cypress programming spec (40-95004). This is caused by the addition of capacitors C4 and C5 to GND on the SCL and SDA output signals. These two signals are sensitive to capacitance so the added 330pF causes failure. The total line capacitance on these lines should be less that 30pF.
Please see the image below to identify the date code on your MiniProg device and see if this issue affects you. If the first two digits of the date codes are 08 or less, then you are affected.
Figure-1, Identify datecode
- Please contact your local Cypress Sales or Customer Marketing representative to initiate a Return Material Authorization (RMA) request. Go to www.cypress.com/sales to find a sales office near you.
- Alternatively, the unit can easily be reworked to achieve full functionality. Simply remove capacitors C4 and C5 to correct this issue. Please see the image below for details.
| Figure-2, Identify Capacitors to be removed | Figure-3, MiniProg board after rework |
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