ZSSC3131
© 2016 Integrated Device Technology, Inc.
The analog output signal is driven by an offset compensated, rail-to-rail output buffer that is current-limited to
prevent damage to the ZSSC3131 in the event of a short circuit between the analog output and power supply or
ground. Output resolution of at least 12-bit in the range of 10% to 90% FS is ensured by a 12.4-bit resistor string
DAC.
2.7. Serial Digital Interface
The ZSSC3131 includes a serial digital I²C
TM
interface and a ZACwire
TM
interface for one-wire communication
(OWI). The digital interfaces allow configuration and calibration of the sensor module. OWI communication can be
used to perform an end-of-line calibration via the analog output pin AOUT of a completely assembled sensor
module. The interfaces also provide the readout of the conditioned sensor signal data during normal operation.
Refer to the ZSSC313x Functional Description for a detailed description of the serial interfaces and the
communication protocols.
2.8. Failsafe Features
The ZSSC3131 detects various failures. When a failure is detected, Diagnostic Mode (DM) is activated. DM is
indicated by setting the output pin AOUT to the Lower Diagnostic Range (LDR). When using digital serial
communication protocols (I²C™ or OWI) to read conditioning results data, the error status is indicated by a
specific error code.
A watchdog timer controls the proper operation of the microcontroller. The operation of the internal oscillator is
monitored by an oscillator-failure detection circuit. EEPROM and RAM content are checked when accessed.
Control registers are parity protected.
Refer to the ZSSC313x Functional Description for a detailed description of failsafe features and methods of error
indication.
2.9. High Voltage, Reverse Polarity, and Short Circuit Protection
The ZSSC3131 is designed for 5V power supply operation.
The ZSSC3131 and the connected sensor are protected from overvoltage and reverse polarity damage by an
internal supply voltage limiter. The analog output AOUT can be connected (short circuit, overvoltage, and reverse
polarity) with all potentials in the protection range under all potential conditions at the pins VDDE and VSSE.
To guarantee this operation, all external components (see application circuit in section 3) are required. The
protection is not time-limited.
Refer to the ZSSC313x High Voltage Protection Description for a detailed description of protection cases and
conditions.
