AD8418WBRZ-RL - 20V/V Bidirectional Zero-Drift Current Sense Amp | ADI
MPN: AD8418WBRZ-RL ✗ Cuối đờiAD8418WBRZ-RL Tóm tắt
A current sense amplifier is a specialized instrumentation amplifier that amplifies the small voltage drop across a shunt resistor to measure load current precisely. It sits within the amplifier IC family, under analog signal conditioning ICs. The AD8418 belongs to the zero-drift amplifier class, which uses chopper stabilization to eliminate offset voltage and drift - a key requirement in closed-loop current control systems where long-term accuracy is essential.
Key features include a 250 kHz bandwidth, a supply current of only 4.1 mA typical, and an internally fixed gain that removes the need for external gain-setting resistors. The zero-drift architecture achieves a maximum offset of ±50 µV (10 µV typical) and a gain drift of ±1 ppm/°C across -40°C to +125°C, while the output stage swings within 50 mV of the rails to maximize dynamic range.
Technically, the AD8418 uses a chopper-stabilized input stage, and its reference pins allow output level shifting for bidirectional current measurement on a single supply. This flexibility supports both unidirectional and bidirectional sensing topologies without negative supplies.
Typical applications include automotive motor control, solenoid control, battery management, and power supply monitoring, where the wide common-mode range and AEC-Q100 qualification ensure reliable operation in harsh environments.
Design tip: drive the reference pins from a low-impedance source and use short shunt traces with proper supply decoupling to avoid gain errors and noise pickup.
Bộ thay thế dễ dàng lắp đặt cho AD8418WBRZ-RL — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
AD8418WBRZ
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
AD8418BRZ-RL
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
AD8418BRZ
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
INA282BID
⚡ Đồng gói ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
AD8418WBRZ-RL Tỷ lệ tối đa & tính chất điện
| Amplifier Type | Bidirectional zero-drift current sense amplifier |
| Kênh | 1 |
| Gain | 20 V/V (fixed) |
| Gain Error | ±0.15% max over temperature |
| Common-Mode Voltage Range | -2 V to +70 V |
| Supply Voltage Range | 2.75 V to 5.5 V |
| Bandwidth | 250 kHz |
| Offset Voltage | ±50 µV max (10 µV typical) |
| Gain Drift | ±1 ppm/°C |
| Điện áp cung cấp | 4.1 mA typical |
| Output Swing | Within 50 mV of rails |
| Nhiệt độ hoạt động | -40°C to +125°C |
| Hộp | 8-lead SOIC |
| Kiểu lắp đặt | Surface Mount |
| Automotive Qualification | AEC-Q100 qualified |
| Packaging | Tape and Reel (-RL) |
| Trạng thái RoHS | Compliant |
Hướng dẫn cấu hình chân AD8418WBRZ-RL 8-lead soic
Cấu hình chân cho AD8418WBRZ-RL (8-lead soic gói). Thành phần số hiệu này có chân đầu vào, đầu ra và nguồn cung cấp. Tham khảo tài liệu thông số kỹ thuật của nhà sản xuất để biết cấu hình chân bù, bù trừ và chân kích hoạt. Hoàn hảo cho điều kiện tín hiệu và mạch khuếch đại.
Không có dữ liệu chân cụ thể sẵn có cho AD8418WBRZ-RL.
Tham khảo: tài liệu kỹ thuật cho cấu hình chân đầy đủ.
Ứng dụng tiêu biểu
AD8418WBRZ-RL phù hợp cho 6 Áp dụngs: Automotive Motor Control Current Sensing, Battery Management Systems, Solenoid and Actuator Control, Power Supply and DC Bus Monitoring, 48V Mild-Hybrid Systems, Industrial Process Control.
Automotive Motor Control Current Sensing
The AD8418WBRZ-RL fits automotive motor control because its -2V to +70V common-mode range tolerates 12V/24V bus transients and its ±0.15% gain error preserves torque-control accuracy in closed-loop FOC schemes. Placed across a shunt in the DC bus or low-side return with a 250 kHz bandwidth, it resolves current ripples for control loops well beyond typical PWM sampling rates, while AEC-Q100 qualification and -40°C to +125°C operation ensure reliability under hood.
Được đề xuất
Battery Management Systems
For BMS pack current monitoring, the AD8418WBRZ-RL's zero-drift offset of ±50 µV max allows accurate measurement with small shunts, minimizing power loss, while ±1 ppm/°C gain drift keeps coulomb-counting accurate over battery life. Its -2V common-mode floor captures charging and regenerative reverse currents on a single supply, and the 20 V/V gain conveniently maps shunt drops into a 5V ADC range without extra gain stages.
Được đề xuất
Solenoid and Actuator Control
Solenoid drivers benefit from the AD8418WBRZ-RL's ability to sense current in high-side configurations up to +70V common-mode, enabling diagnostics of shorted loads and open circuits in 24V industrial and automotive actuators. The 250 kHz bandwidth captures peak-and-hold current waveforms, and the fixed 20 V/V gain simplifies design with no external gain resistors to drift, keeping trip thresholds accurate across temperature.
Được đề xuất
Power Supply and DC Bus Monitoring
In telecom and industrial power supplies, the AD8418WBRZ-RL monitors DC bus current with high-side shunts, where its wide common-mode range survives bus transients that would damage conventional amplifiers. The 10 µV typical offset enables millivolt-level shunt drops to be measured accurately, reducing shunt dissipation, and the output can be level-shifted via the REF pins to match any downstream ADC input range.
Được đề xuất
48V Mild-Hybrid Systems
The AD8418WBRZ-RL's +70V absolute common-mode capability provides headroom for 48V mild-hybrid battery rails and their transient overshoot. Its zero-drift architecture maintains ±0.15% gain accuracy over the full -40°C to +125°C range, supporting accurate load-current reporting to vehicle control units. AEC-Q100 qualification and tape-and-reel supply make it suitable for high-volume automotive production environments.
Được đề xuất
Industrial Process Control
In industrial current-loop and actuator monitoring, the AD8418WBRZ-RL provides a single-supply analog front end with bidirectional sensing via its REF pins, allowing positive and negative current indication around a mid-scale reference. The 4.1 mA supply current suits multichannel systems, and the chopper-stabilized input eliminates offset drift that would otherwise require periodic field calibration of current thresholds.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho AD8418WBRZ-RL — 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 | AD8418WBRZ | AD8418BRZ-RL | INA282BID |
|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Texas Instruments |
| Package | 8-SOIC | 8-SOIC - same | 8-SOIC - same | 8-SOIC |
| Gain | 20 V/V | 20 V/V | 20 V/V | 50 V/V |
| Common-Mode Range | -2 V to +70 V | -2 V to +70 V | -2 V to +70 V | -14 V to +80 V |
| AEC-Q100 | Qualified (W grade) | Qualified (W grade) | Qualified | Not qualified (standard) |
| Lifecycle | NRND | NRND | NRND | Active |
Bảo phân biệt quan trọng
- Zero-drift accuracy with wide common-mode (vsINA282BID)
- Bidirectional sensing on a single supply (vsINA282BID)
- Package choice flexibility within family (vsAD8418WBRMZ-RL)
Ghi chú thiết kế
Use a Kelvin-connected shunt: route the amplifier input traces directly to the shunt resistor pads, not to shared current-carrying copper. With a ±50 µV maximum offset, even 1 mΩ of extra trace resistance adds error at high currents. Keep the input loop short and symmetrical, and place a 0.1 µF decoupling capacitor within 2 mm of the VS pin per Analog Devices layout guidance in the AD8418 datasheet typical application section.
Drive the REF pins from a low-impedance source. Because the reference-to-output gain is 1 V/V, any noise or impedance on REF appears directly at the output; a simple resistor divider without buffering introduces both gain error and offset shift. For bidirectional sensing, buffer the mid-scale reference with an op amp such as the AD8628 or use a precision reference IC.
The AD8418 is listed as NRND - Analog Devices does not recommend it for new designs, so plan a second-source strategy. Also note the WBRZ grade is specified for -40°C to +125°C; lower grades may not meet automotive requirements. Do not exceed the +70V common-mode rating during load-dump events without verifying transient conditions against the datasheet absolute maximum ratings.
Thông tin tuân thủ
RoHS compliance per distributor listings; AEC-Q100 qualification for the W automotive grade per ADI product data. REACH and halogen-free status not stated in provided data.
