SLAA351A April 2007 – November 2018 MSP430F2232 , MSP430F2232 , MSP430F2234 , MSP430F2234 , MSP430F2252 , MSP430F2252 , MSP430F2254 , MSP430F2254 , MSP430F2272 , MSP430F2272 , MSP430F2274 , MSP430F2274
The input signal is captured by a Panasonic WM-61A microphone that has a frequency response between 20 Hz and 20 kHz and can operate at voltages up to 10 V. The microphone has a signal-to-noise ratio of approximately 60 dB. The microphone is turned on every 2 ms when the input signal needs to be captured. This on-and-off mechanism is controlled in software by port pin P4.0 of the MSP430 MCU, which provides the supply voltage of DVCC to the microphone. The maximum current consumption during this capture is approximately 0.5 mA. The microphone is physically disabled by placing a jumper on header X3.