Texas Instruments TLC4545IDGK

Overview

TLC4545IDGK from Texas Instruments is a 16-bit pseudo-differential successive-approximation analog-to-digital converter (SAR ADC) operating from a single 5-V supply, delivering 200-KSPS sampling rate, ±2.5 LSB INL, and 84.5 dB SINAD at 15 kHz input - used in precision industrial measurement and motor control feedback loops.

For engineers reviewing the TLC4545IDGK datasheet, TLC4545IDGK pinout, TLC4545IDGK application, or TLC4545IDGK equivalent, this page provides verified functional identity, validated terminal roles, confirmed timing behavior under SPI/DSP interfaces, and real-world design implications of its auto-power-down mode and rail-to-rail 500 kHz analog input bandwidth.

Technical Context

The TLC4545IDGK implements a charge-redistribution SAR architecture with built-in oscillator-based conversion clock (max 2.94 µs), supporting pseudo-differential input via dedicated AIN(+) and AIN(−) terminals. It requires no external clock source for conversion timing.

Its serial interface operates in three modes: SPI-compatible (CS-controlled), DSP frame-sync–driven (FS input used only on TLC4541), or CS-as-FS mode (TLC4545 uses CS pin exclusively for cycle initiation). Output is unipolar straight binary, MSB-first, with 16-bit resolution and 17th SCLK edge–triggered high-impedance return.

Key Specifications

Pinout & Package

VSSOP-8 (DGK) package: 3.0 mm × 3.0 mm, 0.65 mm pitch, thin-profile surface-mount with exposed pad (not electrically connected).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-bit SAR ADC applications.

Compared with ADS8325IDGK, TLC4545IDGK offers 2× sampling rate and integrated clock but consumes more power; versus TLC4541IDGK, it trades FS pin functionality for pseudo-differential capability in identical DGK packaging - enabling noise-resilient sensing without PCB redesign.

Availability

TLC4545IDGK is available at Aetrix Electronics and suitable for industrial process control, motor control feedback, and automated test equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TLC4545IDGK 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 expertise in precision data converters and industrial-grade ICs.

The TLC4545IDGK belongs to TI's high-performance SAR ADC product line, designed specifically for applications demanding accuracy, low power, and robust serial interfacing in harsh industrial and instrumentation environments.

FAQ

What is the function of pin 5 (AIN(−)) on the TLC4545IDGK?

Pin 5 serves as the inverted analog input for pseudo-differential operation on the TLC4545IDGK. It accepts common-mode signals up to ±0.2 V ripple and enables rejection of ground noise and zero-scale offset without external components. This terminal must be connected to a stable reference or low-impedance node - floating or improperly biased AIN(−) degrades INL and DNL performance in the TLC4545IDGK.

Does the TLC4545IDGK require an external clock for conversion?

No, the TLC4545IDGK does not require an external clock for conversion. It integrates an internal oscillator that generates the conversion clock, resulting in a guaranteed maximum conversion time of 2.94 µs. The external SCLK (pin 7) is used solely for serial data transfer timing - not for ADC core operation - making the TLC4545IDGK simpler to implement than externally clocked SAR ADCs.

How does the auto-power-down mode work on the TLC4545IDGK?

The TLC4545IDGK enters auto-power-down automatically after conversion completion, reducing supply current from 3.5 mA to 5 µA. It wakes up on the next falling edge of CS (pin 1), with no additional setup required. This feature is transparent to timing - the first SCLK after wake-up aligns with standard serial protocol - and is fully supported in both SPI and DSP interface configurations of the TLC4545IDGK.

Can the TLC4545IDGK interface directly with a TMS320 DSP without level-shifting?

Yes, the TLC4545IDGK interfaces directly with TMS320 DSPs using its CS pin (pin 1) as the frame sync input, eliminating need for level shifters. Its digital inputs accept VIH ≥ 2.1 V and VIL ≤ 0.8 V at 5-V VDD, matching standard 3.3-V DSP I/O thresholds when VDD = 5 V. The SDO output drives 3.3-V logic reliably due to VOH ≥ 3.9 V and VOL ≤ 0.4 V - confirmed in electrical characteristics tables for the TLC4545IDGK.

What is the recommended reference voltage range for the TLC4545IDGK?

The TLC4545IDGK requires an external reference voltage applied to pin 2 (REF) within 4.0 V to VDD (5.5 V max). TI specifies optimal performance at VREF = 4.096 V, where THD reaches −94 dB and SNR hits 85 dB. Using VREF < 4.0 V increases gain error and reduces effective resolution; exceeding VDD risks violating absolute maximum ratings. The REF input impedance drops to 20–25 kΩ during conversion - external buffer or low-Z source is recommended for stability in the TLC4545IDGK.