Texas Instruments TLC0838CPW

Overview

TLC0838CPW from Texas Instruments is an 8-bit successive-approximation analog-to-digital converter (ADC) with integrated 8-channel analog multiplexer, serial control interface, and ratiometric operation capability. It delivers ±1 LSB total unadjusted error, 32 µs conversion time at 250 kHz clock, and supports single-ended, differential, or pseudodifferential input configurations across 0 V to 5 V input range using a single 5-V supply. It is used in industrial sensor signal conditioning systems requiring compact, low-pin-count ADC interfacing with microcontrollers via SPI-compatible serial protocol.

For engineers reviewing the TLC0838CPW datasheet, TLC0838CPW pinout, TLC0838CPW application, or TLC0838CPW equivalent, key selection considerations include its TSSOP-20 package, 0°C to 70°C operating temperature range, software-configurable channel addressing, SE/DO/CS/CLK/DI serial timing compatibility with TTL/MOS logic, and absence of internal voltage reference regulator - requiring external REF connection.

Technical Context

The TLC0838CPW implements a sample-data comparator architecture with a 9-bit shift register for multiplexer address and conversion result handling. Its serial interface uses a start bit followed by 3–4-bit configuration word to select channel, polarity, and input mode (SGL/DIF/ODD/EVEN), enabling flexible analog front-end routing without parallel bus overhead.

Conversion begins after CS assertion and address latching; SARS goes high during conversion, and DO outputs MSB-first data synchronized to CLK edges. The device supports both MSB-first and LSB-first output formats controlled by the SE pin, and includes internal resistive ladder DAC and SAR logic for successive approximation, with analog inputs referenced to either ground, adjacent channels, or common (COM) terminal.

Key Specifications

Pinout & Package

TLC0838CPW is housed in a 20-pin TSSOP (Thin Shrink Small Outline Package) with 0.65 mm lead pitch, JEDEC MO-153 compliant, RoHS-compliant NIPDAU lead finish, and MSL Level-1 rating (unlimited floor life at ≤30°C/60% RH).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit serial ADC applications.

Compared with TLC0838CPW, ADC0838CCN trades external reference flexibility for integrated regulation and higher power, while TLC0838IPW retains full compatibility but extends thermal operating envelope - making the latter a drop-in upgrade for harsher environments without altering schematic or layout.

Availability

TLC0838CPW is available at Aetrix Electronics and suitable for industrial sensor interface, embedded data acquisition, motor control feedback, and test & measurement front-end applications requiring stable component supply, long-term manufacturability, and RoHS-compliant TSSOP packaging.

Supply support for TLC0838CPW 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 TLC083x family was designed for cost-sensitive, space-constrained embedded systems needing flexible analog input multiplexing and minimal microcontroller interface overhead - targeting PLCs, instrumentation, and motor control applications.

FAQ

What is the maximum clock frequency supported by the TLC0838CPW?

The TLC0838CPW supports a clock frequency range of 10 kHz to 600 kHz, with a recommended duty cycle of 40% to 60%. At 600 kHz, conversion completes in 13.3 µs (8 clock periods), but timing margins for setup/hold (tsu = 350 ns, th = 90 ns) must be verified in the target system layout. The TLC0838CPW datasheet specifies 250 kHz as the nominal test condition for electrical characteristics.

Does the TLC0838CPW include an internal voltage reference?

No, the TLC0838CPW does not include an internal voltage reference or Zener regulator. It requires an external reference voltage applied to the REF pin, which can range from 0 V to V_CC+0.05 V. This design allows full-scale range adjustment - for example, a 2.5-V REF encodes 0–2.5 V input to all 256 codes - unlike the functionally similar ADC0838, which integrates a 5-V reference.

How is differential input configured on the TLC0838CPW?

Differential input on the TLC0838CPW is configured via the serial address word: adjacent channel pairs (e.g., CH0/CH1, CH2/CH3) are selected with DIF = high and ODD/EVEN bits set to define polarity. The positive input is assigned to one channel and the negative to the other; the output code is zero if the negative input exceeds the positive. This is distinct from pseudodifferential mode, which uses the COM pin as shared negative reference.

Can the TLC0838CPW operate with a 3.3-V microcontroller interface?

Yes, the TLC0838CPW digital I/O (CS, CLK, DI, DO, SARS, SE) is TTL- and MOS-compatible and operates with V_CC = 4.5–5.5 V. When interfaced to a 3.3-V microcontroller, level-shifting is required on inputs (CS, CLK, DI, SE) because VIH(min) = 2.0 V but VIL(max) = 0.8 V - a 3.3-V logic high meets VIH, but 3.3-V outputs driving DI may exceed absolute max input voltage (V_CC + 0.3 V = 5.8 V). DO and SARS outputs swing rail-to-rail and are safe for 3.3-V inputs.

What is the purpose of the COM pin on the TLC0838CPW?

The COM pin on the TLC0838CPW serves as the common analog reference for pseudodifferential input mode. When enabled, it acts as the shared negative input for all eight channels (CH0–CH7), allowing each channel to be treated as the positive side of a differential pair relative to COM. This is especially useful when all analog sensors share a non-ground bias voltage - for example, in single-supply op-amp signal chains biased at V_CC/2.