ZHCSDS3C May 2015 – April 2018 ADS52J90
PRODUCTION DATA.
The device has 16 synchronous ADCs that provide a digital representation of the input in twos complement format. Each ADC converts at a rate of fC using a conversion clock that is internally generated from the system clock. Every cycle of a conversion clock corresponds to a new ADC conversion.
The mapping of the ADC conversions to the analog input is described in Table 3. See Figure 57, Figure 58, and Figure 59 for the naming conventions.
ADC SAMPLE | INPUT CONVERTED BY THE ADC | ||
---|---|---|---|
16-INPUT MODE | 32-INPUT MODE | 8-INPUT MODE | |
ADC1o | AIN1 (t1) | AIN1 (t1) | AIN1 (t1) |
ADC2o | AIN2 (t1) | AIN3 (t1) | AIN1 (t2) |
ADC1e | AIN1 (t2) | AIN2 (t2) | AIN1 (t3) |
ADC2e | AIN2 (t2) | AIN4 (t2) | AIN1 (t4) |
The ADC resolution (the number of bits in the signals marked as ADCOUT1 to ADCOUT16) can be programmed as 10, 12, or 14 bits using the ADC_RES bits. The maximum conversion clock of the ADC depends on the ADC resolution setting, as shown in Table 4.
ADC RESOLUTION (Bits) | MAXIMUM CONVERSION CLOCK (fC(max), MSPS) |
---|---|
10 | 100 |
12 | 80 |
14 | 65 |
The relationship between the system clock and sampling clock rates to the ADC conversion clock is shown in Table 5. Note that the maximum conversion rate of the ADC is fixed for the three resolution modes. In Table 5, sampling rate refers to the effective rate of sampling each active analog input.
ANALOG INPUT MODE (Number of Input Channels) | SYSTEM CLOCK RATE (fS) | SAMPLING RATE (fSAMP)(1) | ADC RESOLUTIONS SUPPORTED |
---|---|---|---|
16 | fC | fC | 10, 12, 14 |
32 | fC | 0.5 × fC | 10, 12, 14 |
8 | 2 × fC | 2 × fC | 10 |