Renesas ZSSC3123AI3B

Overview

ZSSC3123AI3B from Integrated Device Technology (IDT) is a capacitive sensor signal conditioning IC in TSSOP-14 package, designed for high-accuracy capacitance-to-digital conversion with integrated temperature compensation, I²C/SPI/PDM output modes, and EEPROM-based calibration storage. It supports 1.8–5.5 V supply, operates down to 1.8 V, and delivers calibrated sensor and temperature readings for industrial pressure, level, and humidity sensing systems.

For engineers reviewing the ZSSC3123AI3B datasheet, ZSSC3123AI3B pinout, ZSSC3123AI3B application, or ZSSC3123AI3B equivalent, key selection criteria include its configurable update rate (10 ms to 1 s), third-order correction capability, on-chip AFE with programmable gain (GainC 4× option), SOT_TCG/Tco scaling (SotTC 2×), and EEPROM lock features for production calibration security.

Technical Context

The ZSSC3123AI3B implements a fully integrated analog front-end (AFE) with delta-sigma ADC, digital signal processing engine, and nonvolatile EEPROM for storing calibration coefficients, sensor configuration, and device identity. Its architecture supports both continuous measurement (Normal Operation Mode) and command-driven calibration (Command Mode).

It features dual-capacitor input (C0/C1), programmable excitation, temperature sensing via on-die diode, and configurable digital outputs - including I²C (up to 400 kHz), SPI (positive/negative edge), and PDM_C for direct connection to microcontroller PDM interfaces. All communication and configuration are managed through 16-byte EEPROM-mapped registers.

Key Specifications

Availability

ZSSC3123AI3B is available at Aetrix Electronics and suitable for industrial pressure transmitters, automotive HVAC humidity modules, medical respiratory sensors, and consumer smart appliance level detection requiring stable component supply, long-term calibration retention, and robust capacitive signal conditioning.

Supply support for ZSSC3123AI3B includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Integrated Device Technology (IDT), now part of Renesas Electronics, is a fabless semiconductor company specializing in timing, memory interface, RF, and sensor signal conditioning solutions for communications, computing, and industrial markets.

The ZSSC3123AI3B belongs to IDT's cLite™ family of highly integrated capacitive sensor conditioners, engineered specifically for high-precision, low-power, production-calibratable capacitive sensing in cost-sensitive industrial and automotive applications.

FAQ

What is the primary function of the ZSSC3123AI3B?

The ZSSC3123AI3B is a dedicated capacitive sensor signal conditioner that converts differential capacitance inputs (C0/C1) into calibrated digital outputs via I²C, SPI, or PDM. It integrates an ADC, digital correction engine, temperature sensor, EEPROM, and programmable AFE - enabling single-chip, production-ready capacitive sensing without external calibration components. The ZSSC3123AI3B performs real-time third-order temperature compensation and stores full calibration data in on-chip EEPROM.

Does the ZSSC3123AI3B support both I²C and SPI communication simultaneously?

No - the ZSSC3123AI3B supports only one active digital interface at a time, selected via EEPROM configuration (Output Mode register). The interface type is fixed during initialization and cannot be dynamically switched during operation. The ZSSC3123AI3B uses the same physical pins (SCL/SDA for I²C; SS/SCLK/MOSI/MISO for SPI) but relies on EEPROM settings to determine functional assignment - requiring reprogramming to change protocols.

What does the "SotTC 2x" feature do in the ZSSC3123AI3B?

The "SotTC 2x" setting in the ZSSC3123AI3B multiplies the stored SOT_TCG and SOT_TCO temperature coefficient values (EEPROM addresses 09H and 07H) by 2 during runtime correction. This scaling is applied automatically when the corresponding EEPROM bit is set, typically during final calibration to accommodate specific sensor thermal response profiles. It directly affects how the ZSSC3123AI3B computes temperature-compensated capacitance values.

Can the ZSSC3123AI3B operate from a 1.8 V supply while delivering full performance?

Yes - the ZSSC3123AI3B is fully specified to operate from 1.8 V to 5.5 V. At 1.8 V, it maintains full functionality including all output modes (I²C, SPI, PDM), EEPROM read/write, temperature measurement, and third-order correction. The minimum operating voltage of 1.8 V allows direct integration with ultra-low-power microcontrollers and energy-harvesting systems without voltage boosting, preserving the ZSSC3123AI3B's accuracy and update rate specifications.

How is calibration data stored and protected in the ZSSC3123AI3B?

Calibration data for the ZSSC3123AI3B is stored in its 128-byte on-chip EEPROM, which includes ECC protection for single-bit error correction and double-bit error detection. Critical fields - such as calibration coefficients, device ID, and alarm thresholds - reside in user-accessible EEPROM locations (00H–0FH), and can be locked permanently using the "Lock EEPROM" bit. Once enabled, this lock prevents further writes to the first 16 bytes, ensuring calibration integrity in production environments where the ZSSC3123AI3B is deployed.