AD7994BRU-0REEL - 4-Ch 12-Bit 188kSPS SAR ADC I2C 16-TSSOP
부품 번호: AD7994BRU-0REEL ✓ 활성| 수량 | 단가 | 합계 |
|---|---|---|
| 1 | $8.42 | $8.42 |
| 10 | $7.55 | $75.50 |
| 100 | $6.32 | $632.00 |
| 500 | $5.41 | $2,705.00 |
| 1,000 | $4.68 | $4,680.00 |
AD7994BRU-0REEL 개요
A SAR ADC is a type of data converter that performs a binary search through successive approximations against a precision DAC to digitize an analog input, achieving an excellent balance between speed, accuracy, and power consumption for mid-rate applications. Within the broader signal chain hierarchy, the AD7994 sits between the analog front-end (sensors, op-amps, muxes) and the digital controller (microcontroller, FPGA, ASIC), functioning as a power-management-aware mixed-signal IC. ADCs in the 10-12 bit, 100kSPS-1MSPS class are the workhorse of industrial monitoring, portable instrumentation, and embedded sensor readback.
Key features of the AD7994BRU-0REEL include a 188 kSPS throughput rate, a 2 microsecond typical conversion time, single 2.7 V to 5.5 V supply operation, and four single-ended analog input channels with a track-and-hold amplifier that supports input bandwidths up to 11 MHz. The device also provides an automatic cycle mode for sequential channel scanning, pin-selectable I2C addressing via the AS pin for bus sharing, and an automatic shutdown mode that reduces supply current to a typical 1 microamp between conversions.
Technically, the AD7994 uses a charge-redistribution SAR core with an internal clock derived from the I2C SCL line, eliminating the need for an external crystal or oscillator. The integrated 4-channel analog multiplexer and track-and-hold block allow ratiometric or absolute measurements against VDD, and the wide input bandwidth preserves transient integrity for multiplexed signals.
Typical applications include battery monitoring in portable equipment, sensor array reading in industrial control, panel meters and instrumentation, and digital system monitoring of temperature, pressure, or supply rails. Compact 16-lead TSSOP packaging keeps the part footprint compatible with space-constrained designs.
When designing with this part, observe the I2C address-scheme strategy (AS pin logic level) to avoid bus conflicts when multiple AD799x devices share the same controller. Decouple VDD with a 0.1 microfarad ceramic capacitor placed as close as possible to the supply pin, and keep analog traces short and guarded by the AGND pin to minimize digital coupling into the conversion result.
This page synthesizes distributor pricing, cross-brand drop-in alternatives, and practical design notes that are not collected in the bare manufacturer datasheet.
드롭인 대체품: AD7994BRU-0REEL — 동일 패키지, 핀 호환. PCB 재작업이 필요한 다른 패키지 부품은 제외됩니다.
이 시리즈의 변형
다음과 드롭인 호환되는 동일 시리즈 모델: AD7994BRU-0REEL (동일 폼 팩터 및 풋프린트) — 차이점: Resolution, RoHS Status, Input Type, Packaging, Data Interface.
빠른 비교 도구 — 나란히 비교할 대체 부품을 선택하십시오:
AD7994BRU-0
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
AD7994BRUZ-0
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
AD7993BRU-0REEL
✅ 드롭인✓ 재고 있음
$3.4 / 개
데이터시트 보기 →AD7997BRU-0REEL
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
AD7998BRUZ-1REEL7
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
AD7904BRU-REEL
✅ 드롭인✓ 재고 있음
$5.2 / 개
데이터시트 보기 →AD7708BRU-REEL
✅ 드롭인✓ 재고 있음
$6.19 / 개
데이터시트 보기 →AD7994BRU-0REEL 최대 정격 & 전기적 특성
| Number of Channels | 4 |
| 분해능 | 12 bit |
| Architecture | SAR (Successive Approximation) |
| 샘플링 속도 | 188 kSPS |
| Conversion Time | 2 us (typical) |
| Input Type | Single-Ended |
| Input Bandwidth | 11 MHz (track-and-hold) |
| Supply Voltage (VDD) | 2.7 V to 5.5 V |
| 인터페이스 | I2C-compatible (Standard, Fast, High-Speed modes) |
| Address Selection | Pin-selectable via AS pin |
| Sequencer | Automatic cycle mode for sequential channel scan |
| 셧다운 전류 | 1 uA max (automatic shutdown mode) |
| 패키지 | 16-pin TSSOP (RU-16) |
| 동작 온도 | -40C to +125C |
| 실장 유형 | Surface Mount |
| Reel Diameter | 7-inch reel (REEL7 suffix per JEDEC standard packaging) |
| RoHS 상태 | Compliant |
AD7994BRU-0REEL 핀 구성
| 핀 1 | VIN0 — Analog input channel 0 |
| 핀 2 | VIN1 — Analog input channel 1 |
| 핀 3 | VIN2 — Analog input channel 2 |
| 핀 4 | VIN3 — Analog input channel 3 |
| 핀 5 | AGND — Analog ground |
| 핀 6 | REF — Voltage reference input (typically tied to VDD) |
| 핀 7 | SDA — I2C serial data |
| 핀 8 | SCL — I2C serial clock |
| 핀 9 | AS — Address select input (sets I2C address LSB) |
| 핀 10 | NC — Not connected |
| 핀 11 | NC — Not connected |
| 핀 12 | NC — Not connected |
| 핀 13 | NC — Not connected |
| 핀 14 | NC — Not connected |
| 핀 15 | NC — Not connected |
| 핀 16 | VDD — Power supply (2.7 V to 5.5 V) |
일반적인 애플리케이션
AD7994BRU-0REEL 적합 용도: 6 애플리케이션s: Battery Cell Monitoring, Industrial Sensor Array Readback, Digital Panel Meter and Instrumentation, Portable Medical Device Data Logging, Power-Supply Telemetry and Supervision, Smart Building and HVAC Sensor Hub.
Battery Cell Monitoring
The AD7994BRU-0REEL is well suited to battery management because its 2.7 V to 5.5 V supply range directly spans single-cell Li-ion and 3 V coin-cell chemistries without level translation, while the 1 microamp automatic shutdown current between conversions preserves standby battery life. Its 12-bit resolution (0.024 percent FS quantization) yields roughly 1 mV LSB at a 4.2 V full scale, which is adequate for state-of-charge estimation and end-of-discharge detection in packs. The four single-ended channels let a single ADC digitize cell voltage, charge current shunt, pack thermistor, and load-side rail simultaneously, reducing BOM cost. In practice, the part is placed adjacent to the protection IC, with VDD locally bypassed by a 0.1 microfarat ceramic and AGND tied to the cell sense ground to keep ADC error below the shunt amplifier offset.
추천
Industrial Sensor Array Readback
The AD7994BRU-0REEL works well as a sensor-array digitizer in industrial PLCs and remote I/O modules because its 4 single-ended inputs and automatic cycle mode sequentially scan up to four analog signals without CPU intervention, freeing the host microcontroller for control loops. The 188 kSPS throughput comfortably exceeds typical 4-20 mA loop update rates of 100 Hz per channel, leaving margin for oversampling and digital averaging to improve ENOB beyond the rated 12 bits. The 11 MHz track-and-hold bandwidth preserves step-response fidelity for fast multiplexed signals, and the pin-selectable I2C address allows multiple AD7994s on a single bus to monitor dozens of channels. Place the part near the analog connector with short, guarded traces and a star-ground layout to reject ground-noise pickup common in factory environments.
추천
Digital Panel Meter and Instrumentation
The AD7994BRU-0REEL is a strong fit for digital panel meters, multimeters, and bench instrumentation because its 12-bit resolution plus the ratiometric 0-VREF input configuration produces a stable, low-noise display reading when VREF is tied to a precision 2.5 V reference. The 2 microsecond conversion time enables a fresh measurement every display refresh cycle (typically 2-4 Hz) with margin for moving-average filtering. The I2C interface drops straight into microcontroller-driven front panels with minimal GPIO, and the TSSOP-16 footprint allows compact handheld form factors. Drive the ADC input through a buffer op-amp (for high-impedance sources) or a low-side current shunt (for current meters) to keep source-impedance-induced gain error below the 12-bit quantisation threshold.
추천
Portable Medical Device Data Logging
The AD7994BRU-0REEL fits portable medical peripherals such as glucose meters, pulse-oximeters, and wearable patches because of its sub-1 microamp shutdown current, which extends coin-cell life during idle intervals between patient measurements. The 188 kSPS throughput captures pulse-waveform envelopes at sample rates well above the 50 Hz physiological band, enabling accurate peak-detection algorithms. The four single-ended channels accommodate multiple biosensor electrodes in a single device, and the I2C bus shares the same lines used for a downstream BLE SoC, simplifying routing. Use a buffered ECG front-end and ESD protection diodes to meet IEC 60601-1 limits, and qualify the ADC for EMI immunity per IEC 55011 during system-level EMC testing.
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Power-Supply Telemetry and Supervision
The AD7994BRU-0REEL is useful in telecom and server motherboard supervisory subsystems where multiple supply rails (12 V, 5 V, 3.3 V, 1.8 V) must be digitized for fault logging and PMBus-style health monitoring. The wide 2.7-5.5 V supply allows direct sensing of 3.3 V and 5 V rails via resistor dividers, while the four-channel mux covers four rails with one IC, reducing PCB area. The automatic cycle mode simplifies host firmware by sequentially updating all four readings without explicit channel-select commands. The exposed pad on the LFCSP variant (BRUZ) improves thermal dissipation when VDD is tied to a higher-voltage rail, but the TSSOP version remains adequate for typical supervisory applications under 10 mA total current draw.
추천
Smart Building and HVAC Sensor Hub
The AD7994BRU-0REEL is well matched to multi-sensor HVAC and building-automation nodes that combine temperature, humidity, illumination, and airflow signals into one I2C address. The 4-channel mux reads each transducer sequentially, the automatic cycle mode keeps a continuous health log without waking the host MCU, and the 1 microamp shutdown current aligns with energy-harvesting or battery-backed wireless sensor nodes. The I2C bus can be shared with an environmental sensor like the ADT7410, simplifying firmware. Place the ADC adjacent to the analog sensors with shared AGND, and guard the analog traces against switching-noise sources like relay drivers and TRIAC dimmers that couple strongly into long cable runs.
추천
추천 제품 요약
엔지니어링 참조 데이터: AD7994BRU-0REEL — 비교, 설계 지침 및 규정 준수 정보.
선택 가이드
대체품과의 비교
| 파라미터 | 이 제품 | AD7994BRU-0 | AD7994BRUZ-0 | AD7993BRU-0REEL | AD7997BRU-0REEL | AD7998BRUZ-1REEL7 |
|---|---|---|---|---|---|---|
| Package | TSSOP-16 (RU-16) | TSSOP-16 - same | TSSOP-16 - same | TSSOP-16 - same | TSSOP-16 - same | TSSOP-16 - same |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Resolution | 12 bit | 12 bit | 12 bit | 10 bit | 10/12 bit selectable | 12 bit |
| Channels | 4 | 4 | 4 | 4 | 8 | 8 |
| Sampling Rate | 188 kSPS | 188 kSPS | 188 kSPS | 188 kSPS | 188 kSPS | 188 kSPS |
| Interface | I2C (Standard/Fast/HS) | I2C | I2C | I2C | I2C | I2C |
| Supply Voltage | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V |
| Architecture | SAR | SAR | SAR | SAR | SAR | SAR |
주요 차별점
- Lowest shutdown current in this ADC class (vs AD7998BRUZ-1REEL7)
- Pin-selectable I2C addressing without glue logic (vs AD7904BRU-REEL)
- Same 16-pin TSSOP footprint as 10-bit variant for upgrade path (vs AD7993BRU-0REEL)
설계 노트
Decouple VDD (pin 16) with a 0.1 microfarat X7R ceramic capacitor placed within 5 mm of the supply pin to suppress digital switching noise that otherwise couples into the analog conversion result. For multi-rail systems where VDD shares a switching regulator, add a ferrite bead or small RC filter (10 ohm + 1 nanofarad) between the ADC VDD pin and the regulator output to attenuate switching ripple. The REF pin can be tied directly to VDD for ratiometric measurements, but for absolute readings drive REF from a low-noise external reference such as the ADR03. Estimated: at 188 kSPS, the dynamic supply current peaks at roughly 0.5 mA, so the decoupling network must present low impedance above 1 MHz.
Use a star-ground topology that ties the ADC AGND (pin 5) directly to the system analog ground at a single point near the connector, with digital ground on a separate plane that joins analog ground only at the regulator return. Route analog input traces (VIN0-VIN3) as short, parallel, guarded traces away from the SDA/SCL lines; keep at least 3x trace width between analog and digital signals to minimize capacitive coupling. Place any input protection diodes or RC filters within 5 mm of the connector to suppress ESD before the traces radiate pickup into the analog section.
Source impedance above 1 kilohm degrades the AD7994 sample-and-hold acquisition accuracy because the internal sampling capacitor (~20 pF typical) must charge through the source resistance within the acquisition window; place a buffer amplifier (such as the AD8628) immediately ahead of each VIN pin if the source impedance exceeds this limit. Add a small RC anti-alias filter (typically 100 ohm + 1 nanofarad) at each input to limit the input bandwidth below half the sampling rate (94 kHz). Avoid long cable runs directly into the VIN pins; use a differential buffer or instrumentation amp for noisy field wiring.
Do not leave the AS pin floating: tie AS to VDD or AGND to select the I2C address LSB and prevent bus-address contention when multiple AD7994 devices share the same controller. Ensure the I2C SDA line has a pull-up resistor (typically 2.2 kilohm to 10 kilohm depending on bus speed and capacitance) per I2C bus specification; the AD7994 SDA pin is open-drain and cannot drive the line high. Avoid routing SDA/SCL across noisy regions of the board; use guard traces or route them on the inner layer adjacent to a ground plane to maintain signal integrity at 3.4 MHz high-speed mode.
규정 준수 정보
RoHS and REACH compliance per Analog Devices product page; lead-free per TSSOP package marking. Halogen-free status not explicitly stated in the verified web data. AEC-Q100 not applicable for this non-automotive-grade variant.
