Texas Instruments PCM1760U-X

Overview

PCM1760U-X from Burr-Brown (now Texas Instruments) is a 20-bit dual-channel delta-sigma analog-to-digital converter modulator, paired with the DF1760 digital filter to form a complete 48kHz sampling ADC system. It delivers –90dB max THD+N, 108dB typ dynamic range, and 110dB typ SNR in a 28-pin SOIC package, designed for high-fidelity audio digitization in professional and consumer audio equipment.

For engineers reviewing the PCM1760U-X datasheet, PCM1760U-X pinout, PCM1760U-X application, or PCM1760U-X equivalent, key selection considerations include its ±5V analog/5V digital supply requirement, 64× oversampling architecture, 256fs/384fs system clock compatibility, 20-bit serial output format configurability, and bipolar offset calibration support.

Technical Context

The PCM1760U-X implements a fourth-order, 4-bit delta-sigma modulator with dual 2nd-order integrators per channel, operating at 64fs (e.g., 3.072MHz at 48kHz fs). It accepts differential analog inputs (±2.5Vp-p), outputs 4-bit noise-shaped data at 64fs, and relies on external passive components (RIN1=2.2kΩ, C1=C2=2200pF, RT1=470Ω, etc.) to set integrator constants and optimize performance across 30–50kHz sampling rates.

It functions exclusively as the analog front-end modulator in a two-chip ADC solution - the DF1760 performs decimation, filtering, and digital output formatting. The PCM1760U-X provides dedicated integrator input/output pins (In-1L/Out-1L, In-2L/Out-2L, etc.), servo and bandgap decoupling terminals, and supports co-phase conversion with precise timing alignment to the DF1760's Strobe and L/RCK signals.

Key Specifications

Pinout & Package

PCM1760U-X is housed in a 28-pin SOIC (DW) package with gull-wing leads, optimized for compact audio PCB layouts and thermal management in analog-digital mixed-signal designs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel 20-bit delta-sigma ADC applications.

Compared with AK5355VT and CS5361-KS, PCM1760U-X offers unique design flexibility through external integrator tuning and co-phase timing control, making it preferable for applications demanding precise analog-domain optimization and legacy 48kHz studio infrastructure integration.

Availability

PCM1760U-X is available at Aetrix Electronics and suitable for professional audio digitizers, studio mastering systems, and high-end consumer DAC reference designs requiring stable component supply and long-term obsolescence management.

Supply support for PCM1760U-X 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

Burr-Brown Corporation, acquired by Texas Instruments in 2000, specialized in high-precision analog signal conditioning ICs for measurement, audio, and industrial applications.

The PCM1760U-X belongs to Burr-Brown's professional audio ADC family, engineered specifically for low-noise, high-dynamic-range digitization in recording, mastering, and broadcast environments where analog integrity and channel matching are critical.

FAQ

What is the function of the PCM1760U-X in an audio ADC system?

The PCM1760U-X is a 20-bit dual-channel delta-sigma analog-to-digital converter modulator that converts analog audio signals into 4-bit 64fs noise-shaped bitstreams. It must be used with the DF1760 digital filter to produce final 20-bit 1fs output data. PCM1760U-X handles only the analog-domain modulation; all decimation, filtering, and digital formatting occur in the DF1760. Its role is strictly front-end signal acquisition with ultra-low THD+N and high channel separation.

Does the PCM1760U-X support standalone operation without the DF1760?

No, the PCM1760U-X does not support standalone operation. It outputs only 4-bit 64fs noise-shaped data and lacks internal decimation or digital output formatting logic. The DF1760 is mandatory to convert this stream into usable 16- or 20-bit serial PCM data. PCM1760U-X has no digital interface pins for direct microcontroller connection - its D0–D3 outputs feed exclusively into DF1760's D0–D3 inputs.

What are the power supply sequencing requirements for the PCM1760U-X?

The PCM1760U-X requires strict power supply sequencing to prevent latch-up: ±VCC and ±VDD must be applied simultaneously, or +VCC and +VDD must be powered first, followed by –VCC and –VDD. Violating this sequence risks permanent damage. Total supply current is +ICC = 24–36mA, –ICC = –30––45mA, +Idd = 12–18mA, and –IDD = –8––12mA, resulting in ~500mW total power dissipation at ±5V.

How does the PCM1760U-X achieve co-phase conversion, and why is it important?

The PCM1760U-X achieves co-phase conversion by sampling left and right channels simultaneously within the same delta-sigma modulation loop, ensuring identical group delay and phase response. This is implemented via shared clock distribution and matched internal integrator paths. Co-phase conversion is essential for stereo imaging fidelity - it prevents interchannel phase skew that would degrade center image stability and spatial localization in professional audio applications.

Can the PCM1760U-X operate at sampling frequencies other than 48kHz?

Yes, the PCM1760U-X supports 30–50kHz sampling frequencies, including 32kHz, 44.1kHz, and 50kHz, by adjusting external integrator components (RIN1, C1, RT1, etc.) per the values specified in the datasheet's Basic Connection Diagram. Performance parameters like THD+N and dynamic range remain valid across this range when components meet ±2% tolerance and low-voltage-coefficient specifications.