ADCS7478AIMFE - 1MSPS 8-Bit SAR ADC SOT-23-6 | Texas Instruments
MPN： ADCS7478AIMFE ✓ 啟用中ADCS7478AIMFE 概覽
Key specifications include 8-bit resolution, 1 MSPS sampling rate, successive approximation register (SAR) architecture with internal track-and-hold, low power consumption, and an industrial operating temperature range of -40C to +85C. The part is part of the ADCS7476/77/78 family, where the 7476 is 12-bit, 7477 is 10-bit, and 7478 is 8-bit - all sharing the same SOT-23-6 / LLP-8 package footprint and pinout for scalable resolution across designs.
The ADCS7478AIMFE is built on a low-power CMOS process and is intended as a drop-in upgrade path for the legacy Analog Devices AD747x series. Its SAR architecture provides deterministic latency and no pipeline delay, which simplifies event-triggered sampling in microcontrollers and DSPs. The serial output is compatible with SPI, QSPI, MICROWIRE, and many common DSP serial interfaces, allowing direct connection to a wide variety of host processors without glue logic.
Typical applications include portable and battery-powered instrumentation, industrial process control loops, motor control feedback, optical sensor front-ends, and consumer audio/video signal monitoring where compact size, low power, and 8-bit resolution are sufficient. The wide supply range supports both 3.3V and 5V system rails.
When designing with this device, ensure the analog input is bandwidth-limited well below the 1 MSPS Nyquist frequency and that the reference voltage is low-impedance and well-decoupled to avoid conversion noise.
直接替換替代品，適用於 ADCS7478AIMFE — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： ADCS7478AIMFE （相同外形與佔位） — 差異在於 Resolution, Operating Temperature Range, Package, RoHS Status, Input Type.
ADCS7478AIMF
✅ 直接替換聯絡詢價
查看資料表 →ADCS7478AIMF/NOPB
✅ 直接替換📋 參考替代品（不在目錄中）
ADCS7477AIMF/NOPB
✅ 直接替換📋 參考替代品（不在目錄中）
ADCS7476AIMF/NOPB
✅ 直接替換聯絡詢價
查看資料表 →ADCS7478AIMFE 最大額定值與電氣特性
| 解析度 | 8 bits |
| 取樣率 | 1 MSPS |
| Architecture | SAR (Successive Approximation Register) |
| Number of Input Channels | 1 single-ended |
| 封裝 | SOT-23-6 (DBV) |
| Data Interface | SPI, QSPI, MICROWIRE, Serial |
| Input Type | Single-ended analog |
| 工作溫度範圍 | -40C to +85C (industrial) |
| Temperature Grade | Industrial |
| Terminal Form | Gull Wing |
| Number of Terminals | 6 |
| Package Code | LSSOP |
| Process Technology | CMOS |
| Track-and-Hold | Internal |
| RoHS 狀態 | Compliant (NOPB suffix) |
ADCS7478AIMFE 腳位配置
| 腳位 1 | VDD — Analog supply voltage |
| 腳位 2 | GND — Analog ground |
| 腳位 3 | AIN — Analog input |
| 腳位 4 | REF — Reference voltage input |
| 腳位 5 | SDO — Serial data output |
| 腳位 6 | CS/SCLK — Chip select / serial clock (per datasheet, see timing diagram) |
典型應用
ADCS7478AIMFE 適用於 6 應用s: Portable Battery-Powered Instrumentation, Industrial Process Control Loops, Motor Control Current Sensing, Optical Sensor Front-Ends, Audio Signal Monitoring, Consumer White-Goods and Appliance Control.
Portable Battery-Powered Instrumentation
The ADCS7478AIMFE's low-power CMOS process and 8-bit resolution at 1 MSPS make it ideal for portable, battery-powered instruments such as handheld multimeters, digital thermometers, and field data loggers. Its single 2.7V-5.25V supply supports direct operation from a single Li-ion cell or two AA batteries, eliminating the need for a separate analog supply rail. The SOT-23-6 package keeps the analog front-end footprint under 10 mm^2, critical for wearables and pocket-sized instruments.
推薦
Industrial Process Control Loops
The ADCS7478AIMFE suits 4-20 mA loop monitoring and discrete sensor digitisation in industrial control panels. Its 1 MSPS throughput easily captures multiplexed thermocouple, RTD, and pressure-transducer signals after front-end signal conditioning. The industrial -40C to +85C temperature grade and SPI/QSPI/MICROWIRE compatibility with common PLC and DSP hosts simplify integration. The 8-bit resolution is sufficient for setpoint monitoring and threshold alarms where 1% accuracy is acceptable.
推薦
Motor Control Current Sensing
BLDC and stepper motor control loops benefit from the ADCS7478AIMFE's 1 MSPS sampling rate for shunt-current feedback in FOC algorithms. While 8-bit resolution limits precision at low currents, it is sufficient for overcurrent protection, commutation timing, and fault detection. The deterministic SAR latency (no pipeline delay) makes the conversion result available in the same cycle it is sampled, simplifying control-loop timing in real-time motor firmware.
推薦
Optical Sensor Front-Ends
Photodiode and ambient-light sensor digitisation at up to 1 MSPS is a common application for the ADCS7478AIMFE. The single-ended analog input accepts the amplified photodiode current directly via a transimpedance stage. The 8-bit resolution provides 256 brightness levels, sufficient for LED backlight control, automatic gain control, and proximity-sensor thresholding in consumer devices and ambient-light compensation in display panels.
推薦
Audio Signal Monitoring
The ADCS7478AIMFE can digitise audio-bandwidth signals up to Nyquist (500 kHz at 1 MSPS), making it suitable for voice-band monitoring, VU-meter front-ends, and consumer audio level detection. While 8-bit resolution yields only ~48 dB dynamic range (insufficient for high-fidelity audio), it is more than adequate for envelope following, compression control, and ALC (automatic level control) feedback loops in PA systems and intercoms.
推薦
Consumer White-Goods and Appliance Control
Washing machines, dishwashers, and HVAC controllers use the ADCS7478AIMFE to digitise temperature, humidity, and water-level sensors. The 1 MSPS sampling rate supports multiplexed sensor scanning across multiple analog channels via an external mux. The SOT-23-6 footprint and low cost make it ideal for cost-engineered consumer white-goods where 8-bit resolution is sufficient for thermistor-based temperature control loops with hysteresis.
推薦
推薦產品摘要
工程參考資料，適用於 ADCS7478AIMFE — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | ADCS7478AIMF | ADCS7478AIMF/NOPB | ADCS7477AIMF/NOPB | ADCS7476AIMF/NOPB | AD7478AAKSZ-REEL |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Analog Devices |
| Package | SOT-23-6 (DBV) | SOT-23-6 (DBV) - same | SOT-23-6 (DBV) - same | SOT-23-6 (DBV) - same | SOT-23-6 (DBV) - same | SC-70-6 - different footprint |
| Resolution | 8 bits | 8 bits | 8 bits | 10 bits | 12 bits | 8 bits |
| Sampling Rate | 1 MSPS | 1 MSPS | 1 MSPS | 1 MSPS | 1 MSPS | 1 MSPS |
| Architecture | SAR | SAR | SAR | SAR | SAR | SAR |
| RoHS Compliance | Yes (NOPB) | No (non-NOPB) | Yes (NOPB) | Yes (NOPB) | Yes (NOPB) | Yes |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
| Input Channels | 1 single-ended | 1 single-ended | 1 single-ended | 1 single-ended | 1 single-ended | 1 single-ended |
主要差異化特點
- Lowest-cost member of the ADCS747x family (對比ADCS7476AIMF/NOPB (12-bit))
- Pin-compatible upgrade path to higher resolution (對比ADCS7477AIMF/NOPB (10-bit) and ADCS7476AIMF/NOPB (12-bit))
- Explicit drop-in replacement for legacy AD747x (對比AD7478AAKSZ-REEL (Analog Devices))
設計說明
The ADCS7478AIMFE operates from a single 2.7V to 5.25V analog supply on the VDD pin. Decouple VDD with a 10uF tantalum or ceramic bulk capacitor plus a 0.1uF ceramic high-frequency bypass capacitor placed within 5 mm of the VDD pin. Place the capacitors on the same PCB layer as the ADC to minimise lead inductance. A linear LDO (not a switching regulator) is recommended for VDD to avoid coupling switching noise into the analog front-end.
Use a single solid ground plane under the ADC and route analog and digital grounds to a single star point at the ADC's GND pin. Keep the analog input trace short and guarded by ground on both sides to minimise coupling from SPI clock edges. The REF pin trace should also be short and decoupled close to the pin with a 10uF + 0.1uF pair. Avoid routing the SDO and CS/SCLK traces parallel to the AIN trace for more than a few millimetres.
The SAR architecture requires the analog input to settle within the acquisition window. Add a small RC input filter (typically 100 ohm + 10nF) to limit broadband noise, but verify the -3dB cutoff is well above the input signal bandwidth. The internal track-and-hold requires the input impedance seen during sampling to be low enough; for source impedances above 1 kohm, add an input buffer amplifier such as the OPA2333 to prevent acquisition-time distortion.
Common pitfalls with the ADCS7478AIMFE include: (1) sharing the REF pin between multiple ADCs without a buffer, which causes crosstalk and reference droop during simultaneous conversions; (2) driving the analog input from a high-impedance source directly without a buffer, causing gain errors; (3) using a noisy digital supply as VDD which couples noise into the conversion result; (4) forgetting to assert CS high between conversions, which leaves the SDO line in an undefined state.
合規資訊
RoHS compliance indicated by /NOPB suffix per TI part numbering convention. Not AEC-Q100 qualified - industrial temperature grade only. For automotive applications, look at higher-tier TI ADC families.