Texas Instruments ADCS7478AIMF/NOPB

Overview

ADCS7478AIMF/NOPB from Texas Instruments is an 8-bit successive-approximation analog-to-digital converter (SAR ADC) with internal track-and-hold, 1-MSPS throughput, ±0.05 LSB typical INL, 0 to VDD input range, and SPI-compatible serial interface. It operates from a single 2.7-V to 5.25-V supply and delivers 49.7 dB SINAD at 100 kHz input-used in automotive navigation sensors and portable medical instrumentation where compact size and low power are critical.

For engineers reviewing the ADCS7478AIMF/NOPB datasheet, ADCS7478AIMF/NOPB pinout, ADCS7478AIMF/NOPB application, or ADCS7478AIMF/NOPB equivalent, key selection criteria include its 6-pin SOT-23 footprint, supply-as-reference architecture, shutdown mode consuming only 1.5 µW at 3 V, and guaranteed 8-bit no-missing-codes performance across −40°C to 125°C.

Technical Context

The ADCS7478AIMF/NOPB implements a charge-redistribution SAR architecture with integrated track-and-hold, enabling precise sampling of fast-changing analog signals. Its conversion is initiated by the falling edge of CS and synchronized to SCLK, requiring exactly 16 clock cycles for full 12-bit frame output (4 leading zeros + 8 data bits + 4 trailing zeros).

It uses the VDD supply as its reference, eliminating external reference components and simplifying system design. The device supports SPI, QSPI, and MICROWIRE protocols, with digital I/O compatible across 2.7–5.25 V supplies and specified timing margins for reliable interfacing with microcontrollers and DSPs.

Key Specifications

Pinout & Package

ADCS7478AIMF/NOPB is housed in a 6-pin SOT-23 package (1.60 mm × 2.90 mm), optimized for space-constrained PCB layouts in portable and automotive modules.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7478AARMZ-REEL and MCP3002-I/P, ADCS7478AIMF/NOPB uniquely combines supply-as-reference simplicity, 1-MSPS speed, automotive temperature qualification, and 6-pin SOT-23 footprint-making it optimal for space- and power-constrained embedded sensing nodes requiring rapid deployment.

Availability

ADCS7478AIMF/NOPB is available at Aetrix Electronics and suitable for automotive navigation sensors, portable medical instrumentation, industrial motor feedback systems, and FA/ATM equipment monitoring requiring stable component supply across extended temperature ranges.

Supply support for ADCS7478AIMF/NOPB 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 over 50 years of innovation in precision data converters and power management ICs.

The ADCS747x family-including ADCS7478AIMF/NOPB-is designed for high-speed, low-power, supply-referenced data acquisition in automotive, industrial, and portable systems where small footprint and robust operation across −40°C to 125°C are essential.

FAQ

What is the resolution and accuracy specification of the ADCS7478AIMF/NOPB?

The ADCS7478AIMF/NOPB is an 8-bit SAR ADC with guaranteed no-missing-codes performance. Its typical integral non-linearity (INL) is ±0.05 LSB at 25°C and ±0.3 LSB over −40°C to 85°C. Differential non-linearity (DNL) is ±0.07 LSB typical, ensuring monotonic behavior critical for control applications. These values are measured with VDD = 2.7–3.6 V and validated across the full automotive temperature range.

How does the ADCS7478AIMF/NOPB handle power supply as reference, and what impact does that have on system design?

The ADCS7478AIMF/NOPB uses VDD directly as its reference, so the full-scale input range is 0 to VDD. This eliminates the need for an external reference IC, reducing BOM cost and PCB area. Designers must ensure VDD is clean and well-bypassed (0.1 µF + 1 µF near the pin) since any noise or drift on VDD directly affects conversion accuracy. The ADCS7478AIMF/NOPB's LSB step equals VDD/256.

What are the timing requirements for initiating and reading a conversion on the ADCS7478AIMF/NOPB?

A conversion on ADCS7478AIMF/NOPB starts on the falling edge of CS. Exactly 16 SCLK falling edges are required to read the full output frame: 4 leading zeros, 8 data bits (MSB first), and 4 trailing zeros. The SDATA pin exits tri-state after CS falls and returns to tri-state after the 16th SCLK falling edge or CS rising edge-whichever occurs first. Minimum quiet time between conversions is 50 ns.

Does the ADCS7478AIMF/NOPB support shutdown mode, and how much power does it consume in that state?

Yes, ADCS7478AIMF/NOPB features a hardware shutdown mode activated by holding CS high while disabling SCLK. At 3 V, shutdown current is 1.5 µW (0.5 µA); at 5 V, it is 2.5 µW (0.5 µA). This ultra-low power state allows rapid wake-up (<1 µs) and is ideal for battery-operated sensor nodes that sample intermittently. Power resumes fully operational mode on the next CS assertion.

Is the ADCS7478AIMF/NOPB pin-compatible with other members of the ADCS747x family, such as ADCS7476 or ADCS7477?

Yes, ADCS7478AIMF/NOPB shares identical pinout, package (SOT-23-6), and interface timing with ADCS7476 and ADCS7477. All three devices use the same VDD/GND/VIN/SCLK/SDATA/CS arrangement and support SPI-compatible serial communication. However, output framing differs: ADCS7476 outputs 4 leading + 12 data bits, ADCS7477 outputs 4 + 10 + 2 trailing, and ADCS7478AIMF/NOPB outputs 4 + 8 + 4 trailing zeros-requiring firmware adjustment per resolution.