Part Number: MSP430I2041
Support,
We have a critical issue that is preventing us from moving to volume production! We are using MSP430i2041 in an Energy Metering Product and seeing intermittent issues where the MSP is reporting Zero Current or Zero Energy with a load connected. Another issue, we see correct Voltage and Current based on the load but Energy never increases. In both these cases an MSP reset solves the issue. We suspect the device is getting reset due to a glitch. Although this doesn't explain the situation above, we would expect all readings should go to ZERO
Maybe a related issue, we are unable to program via FET using either 10nF or 2.2nF cap on the RSTn line per the data sheet. We have to remove the cap altogether, which definitely makes RSTn susceptible to glitches. Although, we no CAP, and scoping Vcc and RSTn signals, we can inject a high frequency glitch in the order of 'ns' and the system does not reset. This would simulate different loads on the main line.
We thought the HOST MCU was interfering since it controls the RSTn signal during normal use, but at power up, the signal from the HOST is set to High-Z.
We need to know what CAP to use on the RSTn line to accommodate
1. Production line programming with FET - while HOST MCU pin is in High-Z
2. sufficient filtering for normal operation
We are using the FET with Elprotronic tool. There is no option to slow down the JTAG clock. Can you suggest another programming tool that would allow us to slow down the SBW clock?
Regards,
