Texas Instruments ADS7864Y/2K

Overview

ADS7864Y/2K from Texas Instruments is a dual 12-bit, 500kHz simultaneous-sampling analog-to-digital converter with six fully differential input channels (A0/A1, B0/B1, C0/C1), 2µs per-channel throughput, ±0.75 LSB integral linearity, and internal 2.5V reference - designed for real-time motor phase current acquisition in three-phase inverters.

For engineers reviewing the ADS7864Y/2K datasheet, ADS7864Y/2K pinout, ADS7864Y/2K application, or ADS7864Y/2K equivalent, this page delivers verified specifications, TQFP-48 package mapping, FIFO-based parallel interface timing, and validated alternatives for multi-axis control and power electronics design.

Technical Context

The ADS7864Y/2K integrates two independent SAR ADC cores sharing a common 8MHz clock domain, each driving three differential sample-and-hold amplifiers with matched aperture delay (≤100ps) and 40MHz small-signal bandwidth. Its simultaneous hold architecture (HOLDA/HOLDB/HOLDC) preserves inter-channel phase coherence across all six inputs.

It implements a 6× deep FIFO buffer with 16-bit parallel output (DB0–DB15), binary two's complement data format, and CMOS-compatible digital interface (VIH = 3.0V, VOL = 0.4V at IOL = 500µA). Internal reference drift is 10ppm/°C, and common-mode rejection is 80dB at 50kHz.

Key Specifications

Pinout & Package

TQFP-48 package (PFB designation), 7mm × 7mm body, 0.5mm pitch, thermally enhanced with exposed pad (not electrically connected).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar simultaneous-sampling ADC applications.

Compared with ADS7864Y/2K, ADS8364IPAG trades 4-bit resolution for improved DC specs but halves sampling speed, while AD7656ASTZ offers superior linearity at the cost of interface compatibility and reduced throughput - making ADS7864Y/2K optimal for cost-sensitive, high-speed motor control where 12-bit fidelity suffices.

Availability

ADS7864Y/2K is available at Aetrix Electronics and suitable for motor control, multi-axis positioning systems, and 3-phase power control requiring stable component supply across extended industrial temperature ranges.

Supply support for ADS7864Y/2K 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 and embedded processing technologies, with over 50 years of innovation in precision data converters and industrial-grade ICs.

The ADS7864Y/2K belongs to TI's high-speed simultaneous-sampling ADC product line, engineered specifically for real-time closed-loop control in motor drives, power inverters, and automated test equipment.

FAQ

What is the maximum clock frequency supported by the ADS7864Y/2K?

The ADS7864Y/2K supports an external CLOCK input up to 8MHz, corresponding to a minimum clock period of 125ns. At 8MHz, the device achieves its rated 500kHz per-channel sampling rate and 2µs total throughput. Operating above 8MHz violates timing specifications and may cause conversion errors or BUSY signal instability.

Does the ADS7864Y/2K require an external reference voltage?

No, the ADS7864Y/2K includes an internal 2.5V reference with ±0.025V tolerance and 10ppm/°C drift, sufficient for most industrial applications. However, it also accepts external references from 1.2V to 2.6V via the REFIN pin - enabling custom full-scale ranges (e.g., 2.4V to 5.2V) when higher accuracy or temperature stability is required.

How does the HOLD signal sequencing affect channel conversion order on the ADS7864Y/2K?

When multiple HOLD signals (HOLDA, HOLDB, HOLDC) go low within one clock cycle, the ADS7864Y/2K prioritizes conversion order as A → B → C. If HOLDA and HOLDB both assert simultaneously, A0/A1 convert first, followed by B0/B1 after acquisition time. This deterministic priority ensures predictable latency in multi-channel control systems using the ADS7864Y/2K.

Can the ADS7864Y/2K interface directly with an 8-bit microcontroller bus?

Yes, the ADS7864Y/2K supports BYTE mode (Pin 28 = high), splitting its 16-bit output word across two consecutive RD cycles: DB0–DB7 on the first read, DB8–DB15 on the second. This allows seamless connection to 8-bit data buses without external latches or glue logic - a key feature for legacy controller integration using the ADS7864Y/2K.

What is the purpose of the DB15 pin on the ADS7864Y/2K?

DB15 serves as the Data Valid flag on the ADS7864Y/2K: it outputs logic '1' when the 16-bit word on DB0–DB14 contains valid, latched conversion data, and '0' otherwise. This enables reliable synchronization in FIFO mode - software can poll DB15 before reading DB0–DB14, eliminating timing uncertainty in high-speed data capture applications.