Texas Instruments MSP430x4xx Computer Hardware User Manual


 
SD16_A Introduction
22-2 SD16_A
22.1 SD16_A Introduction
The SD16_A module consists of one sigma-delta analog-to-digital converter
with an high impedance input buffer and an internal voltage reference. It has
up to 8 fully differential multiplexed inputs including a built-in temperature
sensor. The converter is based on a second-order oversampling sigma-delta
modulator and digital decimation filter. The decimation filter is a comb type
filter with selectable oversampling ratios of up to 1024. Additional filtering can
be done in software.
Features of the SD16_A include:
- 16-bit sigma-delta architecture
- Up to 8 multiplexed differential analog inputs per channel
- Software selectable on-chip reference voltage generation (1.2V)
- Software selectable internal or external reference
- Built-in temperature sensor
- Up to 1.1 MHz modulator input frequency
- High impedance input buffer
- Selectable low-power conversion mode
The block diagram of the SD16_A module is shown in Figure 22−1.