PCM1740E/2K

ADCs/DACs - Special Purpose Overview

The PCM1740E/2K is a stereo audio digital-to-analog converter (DAC) from Texas Instruments, designed for set-top boxes and digital broadcast receivers. It features an integrated voltage-controlled crystal oscillator (VCXO) generating a 27MHz master clock and a programmable phase-locked loop (PLL). The device utilizes a multi-bit delta-sigma architecture with 8x interpolation filtering. Key electrical specifications include a dynamic range and signal-to-noise ratio of 94dB at 44.1kHz sampling frequency. It supports sampling rates up to 96kHz with 16-, 20-, or 24-bit data resolution via a serial audio interface. Powered by a single +5V supply, it operates within a temperature range of -25°C to +85°C and is housed in an SSOP-24 package.

ADCs/DACs - Special Purpose Feature Summary

• Integrated VCXO providing a precise 27MHz ±150ppm output clock with 0V to 3V tuning input.
• Programmable PLL generates 256fS or 384fS system clocks for standard audio sampling frequencies.
• Multi-bit delta-sigma DAC architecture delivering 94dB dynamic range and -89dB THD+N.
• Supports Standard and I2S™ formats with 16-, 20-, or 24-bit data word lengths.

ADCs/DACs - Special Purpose Applications

• Set-top boxes requiring high-quality audio playback
• Digital broadcast receivers
• MPEG-2 decoding applications

ADCs/DACs - Special Purpose Procurement Notes

Verify the specific ordering suffix '/2K' corresponds to the tape and reel packaging containing 2000 units per reel, as distinct from rail packaging. Confirm component availability status, as older audio ICs may be subject to end-of-life notices or obsolescence. Ensure compatibility with existing PCB footprints for the SSOP-24 package during procurement planning.

ADCs/DACs - Special Purpose Selection Notes

Select this component when a dedicated 27MHz master clock source is required alongside the DAC function. Verify that the application supports a single +5V power supply, as separate analog and digital supplies are not supported. Ensure the host processor can drive the serial audio interface (BCK, LRCK, DATA) and manage the I2C-Bus control registers for attenuation and format configuration.

ADCs/DACs - Special Purpose Part Context

The PCM1740 belongs to the SoundPlus™ family of audio converters. The 'PCM1740E' denotes the commercial temperature grade (-25°C to +85°C) variant. The '/2K' suffix specifically indicates the reel packaging option. This part integrates functions typically found in separate components, such as a VCXO and PLL, reducing bill-of-materials complexity for broadcast equipment.

ADCs/DACs - Special Purpose Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Designers should verify pinout and register compatibility if considering alternative stereo DACs with integrated clock generation.