TLC549CD - 8-Bit 40kSPS SAR ADC Serial Out | Texas Instruments
부품 번호: TLC549CD ✓ 활성| 수량 | 단가 | 합계 |
|---|---|---|
| 1 | $1.95 | $1.95 |
| 10 | $1.71 | $17.10 |
| 100 | $1.42 | $142.00 |
| 500 | $1.18 | $590.00 |
| 1,000 | $1.02 | $1,020.00 |
TLC549CD 개요
A successive-approximation register (SAR) ADC is a converter architecture that uses a binary-search algorithm against an internal digital-to-analog converter to determine each input code, one bit per clock cycle. Compared with integrating or flash ADCs, SAR converters balance moderate speed, low power, and 8-to-18-bit resolution, making them the standard topology for microcontroller peripheral A/D channels and standalone data-acquisition front-ends. The TLC549CD specifically targets low-power applications where serial data transfer to a host processor or peripheral is acceptable in exchange for minimal pin count.
Key features of the TLC549CD include on-chip software-controllable sample-and-hold, differential reference input voltages that allow ratiometric conversion, a 3-state serial data output that simplifies bus sharing with other peripherals, and total access and conversion time of 17 µs max. The part is designed for either microprocessor-peripheral or fully standalone operation, with I/O CLOCK, chip select (/CS), and DATA OUT forming a serial interface compatible with many 8-bit microcontrollers of its era. The 8-pin SOIC package simplifies PCB layout where analog and digital grounds can be cleanly separated.
The TLC549CD integrates a switched-capacitor successive-approximation architecture with 8-bit resolution and an 8-bit on-chip sample-and-hold circuit. The serial interface uses three signals (CS, I/O CLOCK, DATA OUT) and is a subset of the SPI specification, allowing direct connection to most microcontrollers and DSPs. The differential reference inputs permit ratiometric conversion when REF+ and REF- are derived from the input signal chain, improving immunity to absolute reference drift.
Typical applications include digital panel meters, portable instrumentation, temperature and process controllers using sensors such as thermocouples or thermistors, battery monitoring in consumer products, and low-speed data loggers. The serial output makes it well suited to microcontroller systems with limited GPIO availability, and the 5V single-supply operation matches legacy 5V digital rails commonly found in industrial controllers.
When designing with this device, place a 10 µF (or larger) bypass capacitor directly at the VCC pin and keep the analog input traces short and guarded to preserve the 8-bit resolution. The differential reference inputs must be driven from a low-impedance source to maintain conversion accuracy; the reference voltage range sets the full-scale input range (REF- to REF+).
드롭인 대체품: TLC549CD — 동일 패키지, 핀 호환. PCB 재작업이 필요한 다른 패키지 부품은 제외됩니다.
이 시리즈의 변형
다음과 드롭인 호환되는 동일 시리즈 모델: TLC549CD (동일 폼 팩터 및 풋프린트) — 차이점: Package, Architecture, Resolution, Data Interface, RoHS Status.
빠른 비교 도구 — 나란히 비교할 대체 부품을 선택하십시오:
TLC549CDR
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
TLC549ID
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
TLC549CP
✅ 드롭인 ⚠️ 사양 미검증📋 참조 대체품 (카탈로그에 없음)
TLV1549CD
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
ADC0831CCN
✅ 드롭인✓ 재고 있음
$2.24 / 개
데이터시트 보기 →TLC548CD
✅ 드롭인 ⚠️ 사양 미검증📋 참조 대체품 (카탈로그에 없음)
TLC549CD 최대 정격 & 전기적 특성
| 분해능 | 8 bits |
| Sample Rate | 40 kSPS |
| Conversion Time | 17 µs max |
| Conversion Cycles Per Second | 40,000 max |
| Number of Input Channels | 1 |
| Architecture | SAR (Successive Approximation) |
| Input Type | Single-ended, with differential reference inputs |
| Data Interface | Serial, SPI-compatible (3-state DATA OUT) |
| Analog Supply Voltage | 3 V to 6 V |
| Operating Temperature Range (C suffix) | 0°C to +70°C |
| Sample-and-Hold | On-chip, software-controllable |
| 패키지 | 8-SOIC (D) |
| 실장 유형 | Surface Mount |
| RoHS 상태 | Compliant |
| Lead-Free Finish | Yes (NiPdAu over Cu) |
| MSL 레벨 | 1 (per TI datasheet) |
TLC549CD 핀 구성
| 핀 1 | VCC — Analog supply voltage (3 V to 6 V) |
| 핀 2 | ANALOG IN — Analog input channel |
| 핀 3 | REF+ — Upper reference voltage (positive reference input) |
| 핀 4 | REF- — Lower reference voltage (negative reference input) |
| 핀 5 | GND — Analog and digital ground |
| 핀 6 | DATA OUT — Serial 3-state data output |
| 핀 7 | I/O CLOCK — Serial clock input |
| 핀 8 | /CS — Chip select, active low |
일반적인 애플리케이션
TLC549CD 적합 용도: 6 애플리케이션s: Digital Panel Meters, Temperature & Process Controllers, Portable Battery-Powered Instrumentation, Slow-Speed Data Loggers, Industrial Sensor Interface Modules, Consumer Audio & Display Controls.
Digital Panel Meters
The TLC549CD fits digital-panel-meter (DPM) designs with its 8-bit resolution and 40 kSPS sample rate. According to the TI datasheet SLAS067C, the differential reference inputs enable ratiometric conversion when REF- is tied to GND and REF+ to VCC, automatically cancelling supply-rail error from the display driver. The 3-wire SPI-compatible serial interface needs only three microcontroller GPIOs, leaving more pins for LCD-segment drivers and keyboard scan. The 5 V single-supply operation aligns with legacy DPM SoC platforms. Combined with a TL082 input buffer, the TLC549CD typically achieves ±0.5 LSB INL in production DPMs, sufficient for 4-digit readout of analog process variables such as 4-20 mA loop current or 0-10 V transducer outputs.
추천
Temperature & Process Controllers
The TLC549CD is widely used as the A/D input for low-cost temperature and process controllers. Its 8-bit resolution (256 codes) provides ~0.4 °C quantization per LSB over a 100 °C span when paired with a K-type thermocouple amplifier stage, sufficient for HVAC and appliance control. The on-chip software-controllable sample-and-hold per the TI datasheet allows synchronized sampling when scanning through external analog multiplexers. The differential reference inputs permit ratiometric conversion with a precision 2.5 V reference such as the TL431A, improving absolute accuracy. With 40 kSPS worst-case throughput, the part can cycle through up to 4 thermocouple/thermistor channels at 10 kHz per channel in multiplexed designs.
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Portable Battery-Powered Instrumentation
Battery-powered portable data-acquisition tools use the TLC549CD because of its low operating current and 3 V to 6 V supply range. Per the TI datasheet, the part draws a few milliamps during conversion and only nanoamperes in standby, matching the duty-cycled power profile of handheld thermometers, multimeters, and field sensors. The 8-pin SOIC package fits the small PCBs of pocket-sized instruments, and the serial interface connects directly to ultra-low-power MCUs such as the MSP430. At 40 kSPS max throughput, the converter supports 100 Hz full-scale sweeps of slow signals like strain-gauge bridges, while its differential reference inputs reduce the bill of materials by removing a dedicated reference IC in many cost-sensitive designs.
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Slow-Speed Data Loggers
In multi-channel data loggers, the TLC549CD serves as a 40 kSPS front-end ADC, often paired with an external 4051-series analog multiplexer to provide up to 8 differential input channels. The 8-bit conversion preserves the ±1 bit absolute-accuracy class required for environmental monitoring (temperature, humidity, soil moisture, battery voltage). The differential reference inputs allow ratiometric measurement of resistive-sensor bridges without a precision voltage reference, reducing BOM cost. With 4 MHz SPI throughput required from the host, the part is compatible with most 8-bit and 32-bit MCUs used in industrial data-logger SoCs. Its 17 µs conversion time allows channel switching and settling within 1 ms, supporting 1 kHz multi-channel sweeps.
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Industrial Sensor Interface Modules
The TLC549CD provides the ADC core for PLC analog-input and 4-20 mA loop-powered sensor interface cards. Its 3 V to 6 V single-supply operation drops into 5 V PLC backplanes directly. The differential reference inputs accommodate custom scaling networks, allowing a single design to digitize 0-10 V, ±5 V, or 4-20 mA inputs with simple external resistor changes. Per the TI datasheet, the serial data output's 3-state behavior makes it bus-friendly when multiple ADC chips share one MCU serial port - a useful topology in multi-channel PLC modules. The 8-SOIC package is small enough for dense I/O card layouts, and the commercial-temperature CD grade suits enclosed industrial cabinet environments.
추천
Consumer Audio & Display Controls
Consumer products that read potentiometers, push-buttons, or simple analog sensors use the TLC549CD as a low-cost 8-bit ADC. The serial data interface needs only three microcontroller pins, freeing GPIOs for LED drivers, keypads, or displays in toys, white-goods, and small appliances. Its 40 kSPS throughput exceeds the needs of human-interface control loops, while the 5 V supply compatibility matches legacy 5V-only MCUs in cost-sensitive consumer products. The differential reference inputs allow direct ratiometric conversion from a wiper potentiometer, simplifying the bill of materials for volume-control or set-point-input designs. The TLC549CD's industrial heritage and TI's mature supply chain make it a low-risk choice for high-volume consumer production.
추천
추천 제품 요약
엔지니어링 참조 데이터: TLC549CD — 비교, 설계 지침 및 규정 준수 정보.
선택 가이드
대체품과의 비교
| 파라미터 | 이 제품 | TLC549CDR | TLC549ID | TLC549CP | TLV1549CD | ADC0831CCN | TLC548CD |
|---|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments (National Semi heritage) | Texas Instruments |
| Package | SOIC-8 (D) | SOIC-8 (D) - same | SOIC-8 (D) - same | SOIC-8 (D) - same | SOIC-8 (D) - same | SOIC-8 (D) - same | SOIC-8 (D) - same |
| Resolution | 8 bits | 8 bits | 8 bits | 8 bits | 10 bits | 8 bits | 8 bits |
| Sample Rate | 40 kSPS | 40 kSPS | 40 kSPS | 40 kSPS | 38 kSPS | 31 kSPS | 45.5 kSPS |
| Conversion Time | 17 µs max | 17 µs max | 17 µs max | 17 µs max | 21 µs max | 32 µs max | 22 µs max |
| Operating Temperature Range | 0°C to +70°C | 0°C to +70°C | -40°C to +85°C | 0°C to +70°C | 0°C to +70°C | 0°C to +70°C | 0°C to +70°C |
| Supply Voltage Range | 3 V to 6 V | 3 V to 6 V | 3 V to 6 V | 3 V to 6 V | 2.7 V to 5.5 V | 3 V to 6 V | 3 V to 6 V |
| Serial Interface | 3-state SPI, 3-wire | 3-state SPI, 3-wire | 3-state SPI, 3-wire | 3-state SPI, 3-wire | 3-state SPI, 3-wire | 3-state SPI, 3-wire | 3-state SPI, 3-wire |
주요 차별점
- Mature TI serial-ADC with 40 kSPS throughput and proven supply stability (vs ADC0831CCN)
- Pure 8-bit, 40 kSPS - lower cost than 10-bit upgrade (vs TLV1549CD)
- Industrial-temperature drop-in variant available (vs TLC549ID)
설계 노트
Place a 0.1 µF to 10 µF bypass capacitor as close as possible to the TLC549CD VCC pin (pin 1) to minimize reference-noise coupling into the ADC. Separate analog and digital grounds with a star connection at the part's GND pin (pin 5) to avoid digital switching noise corrupting the analog input or REF+/REF-. The 8-SOIC package has a thermal pad that should be soldered for mechanical robustness; though TLC549CD does not dissipate significant power, the pad aids PCB ground plane connection. Trace the analog input (pin 2) with a guarded or differential pair to the source to preserve 8-bit accuracy at low signal levels.
The TLC549CD operates from a single 3 V to 6 V analog supply. Per the TI datasheet, VCC must be decoupled with at least 0.1 µF and ideally a 10 µF bulk capacitor near the device. The differential reference inputs REF+ and REF- set the full-scale input range and should be driven from a low-impedance source (e.g., op-amp buffer); recommended REF- is at least 0.1 V above GND and REF+ is at most VCC - 1.5 V. For ratiometric conversion, tie REF- to GND and REF+ to VCC to automatically ratio out supply noise.
Common pitfalls with the TLC549CD include (1) forgetting the /CS pull-down/up - the chip select input should be tied low when continuously using the device, (2) sampling the DATA OUT on the wrong clock edge - per the TI datasheet, DATA OUT changes on the rising edge of I/O CLOCK and should be read on the falling edge, (3) driving REF+ above VCC - 1.5 V or REF- below GND which violates absolute-maximum ratings, and (4) using excessive source impedance on the analog input - keep input impedance below 10 kΩ to maintain acquisition time. The TLC549CD does NOT have an internal oscillator; an external I/O CLOCK from the MCU must drive conversions.
The TLC549CD's serial interface runs at up to 1 MHz I/O CLOCK; keep the DATA OUT, I/O CLOCK, and /CS traces short and routed together as a 3-wire bus to maintain timing margins. The 3-state DATA OUT allows multiple TLC549CD chips to share one MCU SPI bus if each gets a dedicated /CS line. Place a 10 kΩ pull-up on DATA OUT only if downstream bus capacitance exceeds 50 pF; the part is designed to drive CMOS loads directly. Decoupling capacitors near each VCC pin will minimize digital switching transients coupling into the analog front-end through the VCC pin.
규정 준수 정보
RoHS compliant per TI datasheet SLAS067C and product page. Commercial temperature grade (0C to +70C). Not AEC-Q100 qualified - choose TLC549Q for automotive applications. Lead-free with NiPdAu over Cu finish.
