Scan IF Operation
30-30
Scan IF
30.2.6.2 LC-Sensor Envelope Test
The envelop test measures the decay time of the oscillations after sensor
excitation. The oscillation envelope is created by the diodes and RC filters. The
DAC is used to set the reference level for the comparator, and the comparator
detects if the oscillation envelop is above or below the reference level. The
comparator and AFE outputs are connected to Timer1_A5 and the
capture/compare registers for Timer1_A5 are used to time the decay of the
oscillation envelope. The PSM is not used for the envelope test.
When the sensors are connected to the individual SIFCIx inputs as shown in
Figure 30−16, the comparator reference level can be adjusted for each sensor
individually. When all sensors are connected to the SIFCI input as shown in
Figure 30−17, only one comparator reference level is set for all sensors.
Figure 30−16. LC Sensor Connections For The Envelope Test
Power
Supply
Terminals
SIFCI0
SIFCI
SIFCI1
SIFCI2
SIFCI3
470 nF
AV
CC
DV
CC
DV
SS
AV
SS
SIFVSS
470 nF
SIFCOM
SIFCH1
SIFCH0
SIFCH2
SIFCH3
Summary of Contents for MSP430x4xx Family
Page 1: ...MSP430x4xx Family 2007 Mixed Signal Products User s Guide SLAU056G ...
Page 2: ......
Page 6: ...vi ...
Page 114: ...3 76 RISC 16 Bit CPU ...
Page 304: ...5 20 FLL Clock Module ...
Page 340: ...7 8 Supply Voltage Supervisor ...
Page 348: ...8 8 16 Bit Hardware Multiplier ...
Page 372: ...9 24 32 Bit Hardware Multiplier ...
Page 400: ...10 28 DMA Controller ...
Page 428: ...13 10 Basic Timer1 ...
Page 466: ...15 24 Timer_A ...
Page 522: ...17 30 USART Peripheral Interface UART Mode ...
Page 544: ...18 22 USART Peripheral Interface SPI Mode ...
Page 672: ...23 12 Comparator_A ...
Page 692: ...24 20 LCD Controller ...
Page 746: ...26 28 ADC12 ...