In SX Microcontrollers, SX/B Compiler and SX-Key Tool, repnz_cmpsb wrote:

originator's reply:

+++ aha ! -- thank you, Sparks...  you were right...

+++  the SX-Tech board uses an LM2940CT 5.0 volt regulator...  golly, they all look the same to me -- but unlike the familiar 7805, which accepts up to 30 volts input (and gets pretty warm while dropping the extra 25 volts), the spec sheet for the regulator on the tech-board states that the Max Input Voltage is "Iv=Ov+5" -- and the text states that it cuts out (for some sort of "safety" reason) (probably its own safety) when the input voltage exceeds that 10v level...

+++ so what I was seeing was normal operation.  and I [i][u]must[/u][/i] use a 6-9 volt regulator on the SX-tech board just like is printed on the unit.

+++ but I may indeed use a higher voltage wall-wart on my projects (which is capable of supplying the needed, higher voltage to my motors)...

+++ and I'm guilty of not following clearly printed instructions, and of that, "A-S-S... U-M-E" thing that we all do from time to time...

thank you,

  tommy

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