Texas Instruments ADC78H89CIMTX

Overview

ADC78H89CIMTX from Texas Instruments is a 12-bit, 7-channel, 500 KSPS successive-approximation ADC with independent analog/digital supplies (AVDD: 2.7–5.25 V, DVDD: 2.7 V to AVDD), SPI/QSPI/MICROWIRE-compatible serial interface, and TSSOP-16 packaging. It delivers ±1 LSB INL/DNL, 72.8 dB SNR at 40.2 kHz, and 0.3 µW shutdown power for automotive navigation and portable instrumentation.

For engineers reviewing the ADC78H89CIMTX datasheet, ADC78H89CIMTX pinout, ADC78H89CIMTX application, or ADC78H89CIMTX equivalent, key selection considerations include channel count (7 single-ended AIN1–AIN7), conversion throughput (500 KSPS minimum), low-power operation across 2.7–5.25 V supplies, industrial temperature range (−40°C to +85°C), and SPI-compatible serial timing with 16-cycle throughput.

Technical Context

The ADC78H89CIMTX uses a charge-redistribution SAR architecture with internal track-and-hold, acquiring input in 3 SCLK cycles and completing conversion in 13 SCLK cycles (16 total). Its straight-binary output is clocked MSB-first on DOUT with synchronous DIN loading of the 8-bit control register during the same frame.

It supports dynamic channel selection via ADD2–ADD0 bits in the control register, enabling sequential or arbitrary sampling of AIN1–AIN7 or GND. Power management is controlled solely by CS: low = active (1.5 mW @ 3 V), high = shutdown (0.3 µW @ 3 V), with no power-up delay or dummy conversions required.

Key Specifications

Pinout & Package

ADC78H89CIMTX is packaged in a 16-lead TSSOP (PW package) with 0.65 mm pitch, optimized for compact PCB layouts and thermal performance (θ_JA = 96°C/W on 4-layer board).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-bit SAR ADC applications.

Compared with ADS7822U and ADS8320EB, ADC78H89CIMTX uniquely balances 12-bit resolution, 7-channel multiplexing, 500 KSPS throughput, and ultra-low shutdown power - making it optimal for multi-sensor embedded systems requiring both speed and efficiency.

Availability

ADC78H89CIMTX is available at Aetrix Electronics and suitable for automotive navigation, portable instrumentation, and industrial control systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ADC78H89CIMTX 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and connectivity technologies, with decades of expertise in precision data converters and industrial-grade IC design.

The ADC78H89CIMTX belongs to TI's legacy high-performance SAR ADC product line, engineered specifically for multi-channel, low-power, wide-supply-range applications in automotive, medical, and industrial instrumentation.

FAQ

What is the maximum clock frequency supported by ADC78H89CIMTX?

The ADC78H89CIMTX supports a maximum SCLK frequency of 8 MHz, with ensured AC performance at that rate. Minimum clock frequency is 50 kHz. At 8 MHz, the device achieves its rated 500 KSPS throughput with 16 SCLK cycles per conversion, including acquisition and conversion phases. Operation outside this range may degrade timing margins or violate setup/hold specifications.

Does ADC78H89CIMTX require an external voltage reference?

No, ADC78H89CIMTX does not require an external voltage reference. It uses AVDD as its internal reference, with LSB width equal to AVDD / 4096. This simplifies system design by eliminating reference ICs and associated layout constraints, though AVDD must be clean and well-bypassed (0.1 µF ceramic + 1 µF tantalum) to maintain specified INL and SNR performance.

How many analog input channels does ADC78H89CIMTX support, and how are they selected?

ADC78H89CIMTX supports seven single-ended analog input channels: AIN1 through AIN7. Channel selection is controlled via the 3-bit ADD2–ADD0 field in the 8-bit control register loaded on DIN during each conversion frame. Valid combinations map directly to AIN1–AIN7 or GND, with AIN1 as default at power-up. Selection takes effect on the next CS-fall-triggered conversion.

What is the power consumption of ADC78H89CIMTX in active and shutdown modes?

In normal operation (CS low), ADC78H89CIMTX consumes 1.5 mW typical at 3 V and 8.3 mW typical at 5 V. In shutdown mode (CS high), it draws only 0.3 µW at 3 V or 0.5 µW at 5 V. This ultra-low shutdown current enables rapid power cycling in battery-operated systems without sacrificing wake-up latency or calibration stability.

Is ADC78H89CIMTX compatible with standard SPI interfaces?

Yes, ADC78H89CIMTX is fully compatible with SPI™, QSPI™, and MICROWIRE™ serial protocols. It uses a 4-wire interface (CS, SCLK, DIN, DOUT) with MSB-first straight-binary output, supports clock idling high/low between frames, and requires no special framing or polarity settings. Its timing aligns with standard SPI Mode 0 (CPOL = 0, CPHA = 0) for seamless integration with microcontrollers and DSPs.