Texas Instruments TLC320AD545PTG4

Overview

TLC320AD545PTG4 from Texas Instruments is a single-channel mixed-signal data/fax codec integrating 16-bit sigma-delta ADC/DAC, analog hybrid circuitry, programmable gain amplifiers, and an 8-Ω AT41 speaker driver. It supports up to 11.025 kHz sample rate, operates from 3.3 V or 5 V supplies, and delivers 80 dB SNR+D for ADC and 78 dB for DAC. It is used in fax modems, voice-band data terminals, and legacy telephony interface designs.

For engineers reviewing the TLC320AD545PTG4 datasheet, TLC320AD545PTG4 pinout, TLC320AD545PTG4 application, or TLC320AD545PTG4 equivalent, key selection considerations include its dual-supply flexibility (AVDD/DVDD/MVDD), FS high/low serial mode selectability, transformer reference voltage (2.5 V / 1.5 V), flash write enable output (FLSH_OUT), and differential vs. single-ended hybrid configuration support.

Technical Context

The TLC320AD545PTG4 implements oversampling sigma-delta conversion with internal decimation (ADC) and interpolation (DAC) filters, synchronized frame-based serial communication (DT_FS/DT_SCLK/DT_DIN/DT_DOUT), and software-configurable gain control across three signal paths: Data_In PGA (0/6/12/18 dB), Data_Out PGA (0/–6/–12/–18 dB), and MONOUT amplifier (0/3/6/9/12 dB). Its hybrid section uses external R/C networks to set gain and filter poles.

It features two independent serial communication modes-primary (for 16-bit ADC/DAC data transfer) and secondary (for 16-bit register read/write)-with DT_DIN bit D0 triggering secondary access. The device lacks hardware power-down but supports software-initiated power-down via control register bit D6, preserving register contents while halting conversions.

Key Specifications

Pinout & Package

Package: 48-pin PT (TQFP), 7 mm × 7 mm, 0.5 mm pitch, exposed thermal pad (not electrically connected).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar data/fax codec applications.

Compared with TLV320AIC10IPFB and CS4461-CQZ, the TLC320AD545PTG4 uniquely integrates fax-optimized hybrid circuitry, transformer reference, flash write enable, and AT41 speaker driver - making it irreplaceable in cost-sensitive, space-constrained legacy telephony designs where those functions would otherwise require ≥5 discrete components.

Availability

TLC320AD545PTG4 is available at Aetrix Electronics and suitable for fax modems, voice-band data terminals, and legacy telephony gateways requiring stable component supply across extended product lifecycles.

Supply support for TLC320AD545PTG4 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 decades of heritage in telecommunication interface ICs.

The TLC320AD545PTG4 belongs to TI's legacy mixed-signal data/fax codec family, designed specifically for PSTN-connected devices requiring integrated analog hybrid, programmable gain, and call-progress speaker drive in a single 48-pin TQFP package.

FAQ

What is the maximum sample rate supported by the TLC320AD545PTG4?

The TLC320AD545PTG4 supports a maximum sample rate of 11.025 kHz, determined by the equation DT_FS = DT_MCLK / 512. This rate is optimized for ITU-T V-series fax and data protocols. Higher rates are not supported due to fixed internal decimation/interpolation ratios and analog filter bandwidth limitations specified in the SLAS206C datasheet.

Does the TLC320AD545PTG4 support both 3.3 V and 5 V operation?

Yes, the TLC320AD545PTG4 supports mixed-voltage operation: AVDD, DVDD, and MVDD can each be independently configured for either 3.3 V or 5 V, enabling flexible integration into heterogeneous power domains. DT_REF scales accordingly (2.5 V at 5 V AVDD, 1.5 V at 3.3 V AVDD), and absolute maximum ratings confirm safe operation across both voltage grades.

How does the flash write enable function (FLSH_OUT) work on the TLC320AD545PTG4?

The TLC320AD545PTG4 provides FLSH_OUT (pin 23) as a switched 5 V output capable of sourcing up to 45 mA when FLSH_IN (pin 24) is pulled low. This directly powers the write/erase cycle of external flash memory devices such as Intel 28F400B or AMD Am29F400, eliminating the need for a separate charge-pump or DC-DC converter in fax modem designs.

Can the TLC320AD545PTG4 operate in differential or single-ended analog configurations?

Yes, the TLC320AD545PTG4 supports both configurations. For differential operation, DTRXP/DTRXM and DTTX_OUTP/DTTX_OUTM are used with external hybrid transformers. For single-ended, DTRXP is tied to DT_REF and DTTX_INP is shorted to DTTX_OUTM per datasheet Figure 6–3; DT_BUFP must be left unconnected in this mode to avoid signal coupling.

What serial interface modes does the TLC320AD545PTG4 support?

The TLC320AD545PTG4 supports two frame-sync modes: FS high mode (SI_SEL = DVDD) and FS low mode (SI_SEL = DVSS). Timing differs in activation edge (rising vs. falling) and FS pulse duration, but both use DT_SCLK for bit clocking and support primary (16-bit ADC/DAC) and secondary (16-bit register) transfers on the same four-pin interface (DT_DIN/DT_DOUT/DT_FS/DT_SCLK).