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Bug #1437
closedon resistance of bus switch not acceptable, at least not for Vcc
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Description
As can be seen from the IDTQS3244 data sheet, the ON resistance is higher tham 16 ohms in case of a 3.3V power input (VCC_PHONE).
This causes significant voltage drop over the switch, resulting in way too low supply voltage arriving at the SIM card.
It seems like we really need to re-think the switching concept. A short-time fix might be to supply power from the SIMTRACE to the sim, rather than passing it through. However, even for the CLK/IO/RST signals the 16Ohms might cause significant signal degradation.
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