PCM1794A Converter: Datasheet, Alternatives, Application Circuit

PCM1794A Symbol

PCM1794A Footprint

PCM1794 3D Model

The PCM1794A is a monolithic CMOS integrated circuit that includes stereo digital-to-analogue converters and support circuitry in a small 28-lead SSOP package. The data converters use TI’s advanced segment DAC architecture to achieve excellent dynamic performance and improved tolerance to clock jitter.

Texas Instruments PCM1794ADB technical specifications, attributes, parameters and parts with similar specifications to Texas Instruments PCM1794ADB.

•  24-Bit Resolution

•  Analog Performance:

− Dynamic Range: 132 dB (9 V RMS, Mono)

• 129 dB (4.5 V RMS, Stereo)

• 127 dB (2 V RMS, Stereo)

− THD+N: 0.0004%

•  Differential Current Output: 7.8 mA p-p

•  8× Oversampling Digital Filter:

− Stop-Band Attenuation: –130 dB

− Pass-Band Ripple: ±0.00001 dB

•  Sampling Frequency: 10 kHz to 200 kHz

•  System Clock: 128, 192, 256, 384, 512, or

• 768 fS With Autodetect

•  Accepts 16- and 24-Bit Audio Data

•  PCM Data Formats: Standard, I2S, and Left-Justified

•  Optional Interface Available to External Digital Filter or DSP

•  Digital De-Emphasis

•  Digital Filter Rolloff: Sharp or Slow

•  Soft Mute

•  Zero Flag

•  Dual-Supply Operation:

− 5-V Analog, 3.3-V Digital

•  5-V Tolerant Digital Inputs

•  Small 28-Lead SSOP Package

PCM1794A Functional Block Diagram

A/V Receivers 

DVD Players 

Musical Instruments 

HDTV Receivers 

Car Audio Systems 

Digital Multitrack Recorders 

Other Applications Requiring 24-Bit Audio

The design of the application circuit is very important in order to actually realize the high S/N ratio of which the PCM1794A is capable. This is because noise and distortion that are generated in an application circuit are not negligible.

PCM1794A Typical Application Circuit

In the circuit of Figure 1, the output level is 2 V RMS, and 127 dB S/N is achieved. The circuit of Figure 2 can realize the highest performance. In this case, the output level is set to 4.5 V RMS and 129 dB S/N is achieved (stereo mode). In monaural mode, if the output of the L-channel and R-channel is used as a balanced output, 132 dB S/N is achieved (see Figure 3).

Figure 1

Figure 2

Figure 3

PCM1794A Alternatives

PCM1794A Package

Texas Instruments (TI) is a global semiconductor firm originating in 1958 and nowadays it has over 30,000 employees who design, conduct and sell analogue and product-differentiating embedded processing components in 35 countries. Aimed at changing the world of tech, TI has put great effort into becoming the solution provider coupled with a vision.