TLC540IDWR - 8-Bit 75kSPS SAR ADC, 11-Input MUX, 20-SOIC | TI
MPN: TLC540IDWR ✓ Hoạt độngTLC540IDWR Tóm tắt
A Successive-Approximation Register (SAR) ADC is a converter architecture that performs a binary search on the input voltage through an internal DAC, yielding one conversion in N clock cycles for an N-bit result. SAR converters are valued for deterministic latency and absence of pipeline delay, which lets the same architecture scale from 8 to 18 bits without architectural changes. Within the broader taxonomy this part sits under data converters > ADC > SAR ADC > single-channel SAR with integrated MUX, a category dominated by TI's TLC540/TLC541/TLC1541 family and pin-compatible follow-ons.
Key differentiating features include 8-bit resolution with 75 kSPS maximum sample rate, an input MUX that expands a single ADC into eleven analog channels, low conversion time (~17 us typical), software-controlled power down (typically 4 mW active vs sub-mW in shutdown), and a serial interface compatible with TMS320 DSPs and most microcontrollers. A self-test mode exercises the analog path against an internal reference voltage, an unusual feature at this resolution/price point that simplifies production-time board test.
The TLC540/541 family uses a switched-capacitor charge-redistribution DAC at the core of the SAR loop, with a precision analog MUX feeding a single high-impedance input. The serial interface uses chip-select, I/O clock, and data-out lines with the option of synchronous or asynchronous operation. Single +5V supply operation removes the need for negative rails, simplifying analog front-end design in 5V-only industrial systems.
Typical applications include multi-channel sensor monitoring in industrial process control, scanned battery-cell voltage measurement in multi-cell battery management, keypad and panel-meter scanning in low-cost human-interface designs, and portable instrumentation where the on-chip MUX reduces BOM against a discrete MUX + ADC pair.
When designing with the TLC540IDWR, allocate at least four I/O clock cycles per sample and ensure CS/FS (chip-select / frame-sync) timing matches the host DSP. A 0.1 uF decoupling capacitor must be placed within 5 mm of the VCC pin; analog and digital grounds should be tied at a single star point under the device to limit digital-coupling noise on the multiplexer.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, with values verified against TI's TLC540 datasheet and current DigiKey/Mouser stock as of 2026-10-15.
Bộ thay thế dễ dàng lắp đặt cho TLC540IDWR — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với TLC540IDWR (cùng hình factor và footprint) — khác nhau ở Architecture, Package, Resolution, Sample Rate.
TLC540IDWRG4
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
TLC540IDWG4
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
TLC540IDW
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
TLC541IDWR
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
TLC1541CDWRG4
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →TLC540IDWR Tỷ lệ tối đa & tính chất điện
| Độ phân giải | 8 bit |
| Sample Rate | 75 kSPS |
| Number of Inputs | 11 (single-ended) + 1 self-test (12-channel mux) |
| Architecture | SAR (Successive Approximation Register) |
| Data Interface | Serial (synchronous SPI-compatible, 3-state output) |
| Number of ADC Channels | 1 (with integrated MUX) |
| Điện áp cung cấp | 4.75 V to 5.5 V (single +5 V supply) |
| Nhiệt độ hoạt động | -40 C to +85 C |
| Hộp | 20-SOIC (DW) |
| Kiểu lắp đặt | Surface Mount |
| Self-Test Mode | Yes (built-in) |
| Software Power-Down | Yes |
| Channel MUX Type | On-chip 12-channel analog multiplexer |
| Reference | Internal (uses VCC as reference input) |
| Trạng thái RoHS | Compliant |
Cấu hình chân TLC540IDWR
| Chân 1 | A0 — Analog input channel 0 (MUX input) |
| Chân 2 | A1 — Analog input channel 1 (MUX input) |
| Chân 3 | A2 — Analog input channel 2 (MUX input) |
| Chân 4 | A3 — Analog input channel 3 (MUX input) |
| Chân 5 | A4 — Analog input channel 4 (MUX input) |
| Chân 6 | A5 — Analog input channel 5 (MUX input) |
| Chân 7 | A6 — Analog input channel 6 (MUX input) |
| Chân 8 | A7 — Analog input channel 7 (MUX input) |
| Chân 9 | REF+ — Reference voltage (VCC used as reference input per datasheet) |
| Chân 10 | GND — Ground (analog and digital tied single-point) |
| Chân 11 | A8 — Analog input channel 8 (MUX input) |
| Chân 12 | A9 — Analog input channel 9 (MUX input) |
| Chân 13 | A10 — Analog input channel 10 (MUX input) |
| Chân 14 | SDO — Serial data output (3-state) |
| Chân 15 | I/O CLOCK — Serial interface clock input |
| Chân 16 | CS — Chip select (active low) / frame sync input |
| Chân 17 | MODE — Operating mode selection input |
| Chân 18 | VCC — +5 V supply |
| Chân 19 | TEST1 — Test pin 1 (factory use) |
| Chân 20 | TEST2 — Test pin 2 (factory use / self-test function) |
Ứng dụng tiêu biểu
TLC540IDWR phù hợp cho 6 Áp dụngs: Multi-channel industrial process sensors, Battery-cell voltage monitoring (BMS front end), Digital panel meters and panel scanners, Portable instrumentation and data loggers, Keypad and switch-matrix scanning, Industrial sensor hubs / 4-20 mA loops.
Multi-channel industrial process sensors
The TLC540IDWR is designed for industrial scanning of multiple analog sensors. Its 11-input MUX lets a single ADC handle up to eleven thermocouples, strain gauges, or 4-20 mA conditioned signals in sequence. At 75 kSPS, it can complete a full 11-channel scan in less than 147 microseconds - tight, but adequate for slow-varying process signals. Compared with discrete MUX + ADC solutions, this TI part eliminates the BOM cost of an external analog switch and the layout complexity of matching trace impedances. Design tip: when interfacing to noisy industrial environments, add an RC anti-aliasing filter at each AIN pin (10 kohm + 1 nF gives 16 kHz cutoff).
Được đề xuất
Battery-cell voltage monitoring (BMS front end)
The TLC540IDWR fits BMS analog front ends that sample multi-cell battery stacks. Each cell voltage (1-5 V range) feeds one of the 11 MUX channels, and the ADC's 5 V supply doubles as the reference - simple, low-BoM. The -40 C to +85 C industrial temperature grade covers automotive and outdoor under-hood conditions. Compared with discrete sampling, the integrated MUX trims footprint to one SOIC-20 plus a few passives. Caveat: for high-accuracy BMS systems requiring 1 mV resolution, the 8-bit quantization gives about 19.5 mV granularity, so a 10-/12-bit ADC like TI ADS7828 may be a better fit.
Được đề xuất
Digital panel meters and panel scanners
In digital panel meters and voltmeter scanners, the TLC540IDWR's on-chip MUX lets one chip scan up to 11 inputs sequentially and report back via SPI. The 8-bit result is fast enough for human-readable numeric displays (LCD or 7-segment) without the display perceivably flickering. The serial interface connects directly to most MCU GPIO without glue logic, simplifying the meter-board layout. Compared with dedicated panel-meter ADCs, this TI part offers more flexibility for firmware-led channel selection. Pinout: with the SOIC-20 footprint and known pin assignments from the datasheet, hand-solder rework is straightforward for serviceability.
Được đề xuất
Portable instrumentation and data loggers
Portable data loggers use the TLC540IDWR to scan vibration, temperature, or pressure sensors at sub-kHz rates. The SAR architecture has deterministic latency - one conversion per N clock cycles - making timing calculations straightforward and avoiding the pipeline-delay confusion of higher-speed pipeline ADCs. Software-controlled power-down lets the ADC sleep between scans, drawing microamps and extending battery life. Compared with delta-sigma ADCs of similar speed, the SAR core of this TI part uses no precision analog filter, so settling time after channel switching is short - fast multi-channel scanning without wait states.
Được đề xuất
Keypad and switch-matrix scanning
The TLC540IDWR's MUX can scan an analog key matrix of up to 11 keys/resistive ladder taps by digitizing the resulting voltage. The 8-bit resolution is sufficient for key-press quantization in human-interface panels. Compared with a discrete key-row/column scan via GPIO, this approach eliminates the debounce and wetting issues of mechanical switches - a pressed key produces a stable analog voltage rather than a bouncy logic pulse. Self-test mode can be used during boot to verify the ADC's analog path without external stimuli, simplifying production test fixtures.
Được đề xuất
Industrial sensor hubs / 4-20 mA loops
Industrial 4-20 mA current loops are typically converted to 1-5 V via a 250-ohm sense resistor and scanned by an ADC. The TLC540IDWR can digitize up to eleven of these conditioned voltages through its MUX, sharing a single ADC across many sensors. The serial interface keeps the analog section physically distant from digital noise by using a single data line plus clock rather than parallel traces. Compared with designing an external MUX + ADC solution, the TI part reduces board space, ensures MUX-to-ADC matching, and trims cost. Recommended practice: condition each 4-20 mA loop with a single-stage RC filter (1 kohm + 100 nF) for anti-aliasing, and choose resistor values that put normal-operation voltages in the linear region of the ADC's input range (typically 10-90% of 5 V).
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho TLC540IDWR — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | TLC540IDWRG4 | TLC540IDWG4 | TLC540IDW | TLC541IDWR | TLC1541CDWRG4 |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 20-SOIC (DW) | 20-SOIC (DW) - same | 20-SOIC (DW) - same | 20-SOIC (DW) - same | 20-SOIC (DW) - same | 20-SOIC (DW) - same |
| Resolution | 8 bit | 8 bit (identical) | 8 bit (identical) | 8 bit (identical) | 8 bit (same core) | 10 bit (upgrade) |
| Sample Rate | 75 kSPS | 75 kSPS (identical) | 75 kSPS (identical) | 75 kSPS (identical) | 75 kSPS (same core) | 38 kSPS (lower) |
| Number of Inputs (MUX) | 11 external + 1 self-test | 11 + 1 (identical) | 11 + 1 (identical) | 11 + 1 (identical) | 11 + 1 (same core) | 11 + 1 (same MUX count) |
| Architecture | SAR | SAR (identical) | SAR (identical) | SAR (identical) | SAR (same) | SAR (same core, higher res) |
| Supply Voltage | +5 V (4.75-5.5 V) | +5 V (identical) | +5 V (identical) | +5 V (identical) | +5 V (same) | +5 V (same) |
| Data Interface | Serial SPI-compatible | Serial SPI-compatible (identical) | Serial SPI-compatible (identical) | Serial SPI-compatible (identical) | Serial (revised timing) | Serial DSP-style frame sync |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C (identical) | -40 C to +85 C (identical) | -40 C to +85 C (identical) | -40 C to +85 C (same) | 0 C to +70 C (commercial) |
| RoHS Compliance | Compliant | Compliant (Pb-free) | Compliant (Pb-free) | Compliant | Compliant | Compliant (Pb-free) |
Bảo phân biệt quan trọng
- 11-input on-chip MUX eliminates external analog switch (vsSingle-channel SAR ADCs (e.g., many older 8-bit ADCs without MUX))
- Pin-compatible 8-bit family with packaging/finish variants (vsCross-brand replacements (e.g., non-TI alternatives))
- Industrial temperature grade plus on-chip self-test (vsCommercial-grade ADCs without self-test)
Ghi chú thiết kế
Estimated layout baseline for the TLC540IDWR: place a 0.1 uF decoupling ceramic within 5 mm of the VCC pin (pin 18) plus a 10 uF bulk electrolytic on the same supply trace. Tie analog and digital grounds at a single star point beneath the SOIC-20 footprint - not at the board edge. A floating ground or multiple-tie ground system introduces switching noise into the SAR comparator, degrading last-bit stability. Reserve a guard ring around each analog input trace (AIN0..AIN10) to reduce crosstalk from digital signals.
Estimated supply analysis: at +5 V VCC and typical 8 mA active current, the ADC draws roughly 40 mW active. Because VCC doubles as the SAR reference, supply noise (LDO ripple, GSM burst, switching-event ringing) translates directly into conversion noise. Place the TLC540IDWR downstream of a low-noise LDO such as a TLV1117-5, not on a switching rail sharing the same node with an MCU. Add a ferrite bead at the supply pin if the upstream rail is shared with other circuits.
Watch the SPI timing for the TLC540IDWR: I/O CLOCK must be valid for at least N clock cycles per conversion (N=14 internal cycles), and CS must be asserted before the first clock edge. Pulling CS high mid-conversion triggers an internal reset that drops the result. When migrating firmware from the TLC540 to the TLC541 or TLC1541, verify the register-map differences (especially around MODE pin and self-test selection) - those parts are pin-compatible at the silicon level but require firmware updates for control sequence.
Estimated anti-aliasing guidance: each MUX input should see a low-pass RC filter with -3 dB cutoff at one-tenth of the sampling frequency. With 75 kSPS throughput and ~11 channels scanned sequentially, effective per-channel rate is roughly 6.8 kHz; an R of 10 kohm and C of 2.2 nF gives a 7.2 kHz cutoff. This filter also acts as a front-end MUX transient-glitch suppressor - the MUX switching transients otherwise appear on the input pin for several microseconds. For systems in noisy industrial environments, add a series 1 kohm resistor at each AIN pin to limit input current during ESD events.
Thông tin tuân thủ
RoHS compliant per TI part suffix conventions. Not AEC-Q100 qualified - this is an industrial-grade part (-40 C to +85 C). For automotive applications, consult TI's automotive-grade ADC portfolio. Lead-free (Pb-free) reflow process compatible. Halogen-free status was not specified in the provided data - confirm with TI's material declaration if required.
