ZSSC3154 Datasheet

R36DS0046ED0160 Rev.1.50

Apr 19, 2024

Page 14

3.8.3

Analog-to-Digital Converter

The analog-to-digital converter is implemented using the full differential switched-capacitor technique. The A/D

resolution is 14-bit. The ADC operates in the second order configuration. The conversion is largely insensitive to

short-term and long-term instabilities of the clock frequency. The ADC must be configured for the following

features:

■

Adjustable A/D conversion time and integration phase length

■

Adjustable A/D conversion input voltage range

Table 7. ADC Resolution versus Output Resolution and Sample Rate

ADC Resolution

rADC

ADC Resolution

Integration Phase

Bridge Sensor Signal

Sample Rate

fOSC = Nominal

Averaged Bandwidth

fOSC = Nominal

14-bit

10-bit

0.60kHz

225Hz

9-bit

1.13kHz

425Hz

8-bit

2.03kHz

765Hz

7-bit

2.54kHz

955Hz

3.9

Signal Outputs

3.9.1

Analog Output

ZSSC3154 provides two analog outputs at the AOUT1 and AOUT2 pins. The analog output behavior and the

assignment of the several conditioned sensor signals to the analog outputs are configurable:

■

Conditioned bridge sensor signal is always assigned to and continuously output at the AOUT1 pin.

■

Conditioned temperature signal can be assigned to the analog output at the AOUT2 pin.

■

Conditioned half-bridge signal can be assigned to the analog output at the AOUT2 pin.

■

A function of the conditioned bridge sensor signal can be assigned to the analog output at the AOUT2 pin.

■

A sequential analog output mode can be assigned to the analog output at the AOUT2 pin. The sequence of

output signals includes the diagnostic fault band HIGH and LOW level, the conditioned temperature or the

half-bridge signal, and a function of the conditioned bridge sensor signal (refer to section 3.9.2).

■

Both analog outputs support low-pass filtering of the assigned conditioned sensor signals.

■

Both analog outputs can support diagnostic procedures of the application by providing a power-on diagnostic

output waveform.

For a detailed description of analog output modes and their configuration, refer to the ZSSC3154 Functional

Description.

3.9.2

Sequential Analog Output

The sequential analog output mode allows the analog output of two conditioned sensor signals at the AOUT2

pin. The sequence of output signals includes both the low and high diagnostic fault band levels (DFB Low and

DFB High, respectively) for synchronization and for a repeated verification of diagnostic levels. This is followed

by output of the conditioned temperature or half-bridge signal to provide the second signal. The last transmission

in the sequence is a function of the conditioned bridge sensor signal for verification of the analog output at the

AOUT1 pin.