Texas Instruments TLC1549IP

Overview

TLC1549IP from Texas Instruments is a 10-bit switched-capacitor successive-approximation analog-to-digital converter with integrated sample-and-hold, serial three-wire interface (CS, I/O CLOCK, DATA OUT), ±1 LSB total unadjusted error, and operation over –40°C to 85°C. It delivers ratiometric conversion via differential high-impedance reference inputs (REF+, REF–) and supports microcontroller-based data acquisition in industrial sensor interfaces.

For engineers reviewing the TLC1549IP datasheet, TLC1549IP pinout, TLC1549IP application, or TLC1549IP equivalent, key selection criteria include its 21 µs conversion time, 2.1 MHz max I/O CLOCK frequency, CMOS-compatible 3-state serial output, and compatibility with TLC549/TLV1549 terminal layouts - all critical for legacy system upgrades and low-pin-count embedded ADC integration.

Technical Context

The TLC1549IP implements a charge-redistribution successive-approximation architecture using binary-weighted capacitors, where sampling begins on the third falling edge of I/O CLOCK and holds on the tenth. Its internal system clock eliminates external timing components, and the threshold detector compares capacitor node voltages against REF– to determine each bit from MSB to LSB.

It supports six serial interface modes defined by CS state (active-low continuous vs. toggled) and I/O CLOCK count (10, 11–16), enabling flexible timing alignment with host processors. Input impedance is 1 kΩ during sampling and 5 MΩ during hold, with 60 pF typical input capacitance - parameters directly tied to external driving source requirements (≤1 kΩ impedance, ≥10 mA drive capability).

Key Specifications

Pinout & Package

Package: 8-pin plastic DIP (P package), through-hole mounting, industry-standard footprint compatible with socketed prototyping and industrial PCBs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 10-bit serial ADC applications.

Compared with TLC549CP, the TLC1549IP provides guaranteed performance at –40°C, making it suitable for outdoor or uncontrolled-temperature industrial sites; compared with TLV1549IPW, it reduces system-level design effort by integrating reference handling and clock generation - critical for rapid prototyping and cost-sensitive production.

Availability

TLC1549IP is available at Aetrix Electronics and suitable for industrial sensor interfaces, motor control feedback monitoring, power supply voltage supervision, and legacy microcontroller data acquisition requiring stable component supply across extended temperature ranges.

Supply support for TLC1549IP 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 precision data converters and industrial-grade ICs.

The TLC1549IP belongs to TI's legacy precision ADC product line, designed specifically for cost-sensitive, low-pin-count industrial data acquisition systems requiring robustness, simplicity, and long-term availability.

FAQ

What is the maximum I/O CLOCK frequency supported by the TLC1549IP?

The TLC1549IP supports a maximum I/O CLOCK frequency of 2.1 MHz under recommended operating conditions (VCC = 4.5 V to 5.5 V, TA = –40°C to +85°C). Exceeding this frequency risks violating setup/hold timing, causing data corruption or loss of synchronization. The device's internal timing is optimized for reliable operation up to this limit, and all electrical characteristics - including conversion time (21 µs) and DATA OUT delay (240 ns) - are specified at 2.1 MHz.

Does the TLC1549IP require an external clock source?

No, the TLC1549IP does not require an external clock source. It incorporates an on-chip system clock that drives the successive-approximation process and internal state machine. The I/O CLOCK signal provided by the host processor serves only as a serial interface timing reference - controlling sampling windows and data shifting - not as the core conversion clock. This eliminates the need for crystals, oscillators, or clock generators in the system design.

How does the TLC1549IP handle analog input impedance during sampling?

The TLC1549IP presents 1 kΩ input impedance during the sampling phase (I/O CLOCK edges 3–10) and 5 MΩ during hold mode. To ensure accurate conversion, the analog source must have ≤1 kΩ output impedance and ≥10 mA drive capability. Higher source impedance causes incomplete capacitor charging, leading to gain and linearity errors. The 60 pF typical input capacitance further dictates that source impedance and drive strength jointly determine settling time before the 10th clock edge.

Is the TLC1549IP pin-compatible with other members of the TLC1549 family?

Yes, the TLC1549IP shares identical pinout and terminal functions with all variants in the TLC1549 family - including TLC1549CP, TLC1549CD, TLC1549ID, and TLC1549MFK - across D, P, JG, and FK packages. Pin 1 (REF+), Pin 2 (ANALOG IN), Pin 3 (REF–), Pin 4 (GND), Pin 5 (CS), Pin 6 (DATA OUT), Pin 7 (I/O CLOCK), and Pin 8 (VCC) retain consistent roles and electrical behavior, enabling direct substitution where temperature and packaging requirements align.

What is the meaning of "total unadjusted error" for the TLC1549IP?

For the TLC1549IP, total unadjusted error is the combined deviation - expressed in LSB - encompassing linearity error (±1 LSB), zero-scale error (±1 LSB), and full-scale error (±1 LSB), measured without calibration or trimming. It represents the worst-case deviation between the actual transfer function and the ideal straight-line response across the full input range. The datasheet specifies this as ±1 LSB maximum, guaranteeing monotonic operation and no missing codes over the entire –40°C to +85°C operating range.