Overview
The AD8218BRMZ-R7 from Analog Devices Inc. is a high-voltage, high-resolution current shunt amplifier designed for precise current sensing in various industrial and telecommunications applications. This device features a zero-drift core, ensuring excellent ac and dc performance. It operates over a wide temperature range of −40°C to +125°C and offers a set gain of 20 V/V with a maximum ±0.35% gain error. The AD8218BRMZ-R7 is particularly useful for high-side current sensing, bidirectional motor control, and precision high-voltage current sources.
Key Specifications
| Parameter | Value | Unit | Test Conditions/Comments |
|---|---|---|---|
| GAIN | 20 | V/V | Initial, Accuracy ±0.1% at VO ≥ 0.1 V dc, TA |
| GAIN Accuracy over Temperature | ±0.35% | TOPR | |
| GAIN vs. Temperature | ±5 ppm/°C | TOPR | |
| VOLTAGE OFFSET | ±200 µV | Offset Voltage (RTI1) at 25°C | |
| VOLTAGE OFFSET Over Temperature | ±300 µV | TOPR | |
| VOLTAGE OFFSET Drift | ±100 nV/°C | TOPR | |
| INPUT Bias Current | 220 µA | TA, input common mode = 4 V, VS = 4 V | |
| Common-Mode Input Voltage Range | 4 V to 80 V | ||
| Differential Input Voltage Range | 0 V to 250 mV | ||
| Supply Voltage Range | 4 V to 5.5 V | VS must be less than 5.5 V if standalone supply is used | |
| Quiescent Current over Temperature | 800 µA | Throughout input common mode | |
| Power Supply Rejection Ratio (PSRR) | 90 dB to 110 dB | TOPR | |
| TEMPERATURE RANGE For Specified Performance | −40°C to +125°C |
Key Features
- High common-mode voltage range: 4 V to 80 V operating, −0.3 V to +85 V survival.
- Buffered output voltage with a gain of 20 V/V.
- Wide operating temperature range: −40°C to +125°C.
- Excellent ac and dc performance with ±100 nV/°C typical offset drift and ±50 µV typical offset voltage.
- Zero-drift core architecture.
- High common-mode rejection ratio (CMRR) of 110 dB at dc.
- Bidirectional current measurements across a shunt resistor.
- Linear ground-referenced analog output when the shunt is battery referenced.
Applications
- High-side current sensing.
- 48 V telecom systems.
- Power management.
- Base stations.
- Bidirectional motor control.
- Precision high-voltage current sources.
- Battery management.
- Base station power amplifier bias control.
Q & A
- What is the operating temperature range of the AD8218BRMZ-R7?
The AD8218BRMZ-R7 operates over a temperature range of −40°C to +125°C. - What is the gain of the AD8218BRMZ-R7?
The gain of the AD8218BRMZ-R7 is 20 V/V. - What is the common-mode input voltage range of the AD8218BRMZ-R7?
The common-mode input voltage range is from 4 V to 80 V. - What is the differential input voltage range of the AD8218BRMZ-R7?
The differential input voltage range is from 0 V to 250 mV. - What is the typical offset voltage of the AD8218BRMZ-R7?
The typical offset voltage is ±200 µV at 25°C. - What is the common-mode rejection ratio (CMRR) of the AD8218BRMZ-R7?
The CMRR is typically 110 dB at dc. - Can the AD8218BRMZ-R7 perform bidirectional current measurements?
Yes, the AD8218BRMZ-R7 can perform bidirectional current measurements across a shunt resistor. - What are some typical applications of the AD8218BRMZ-R7?
Typical applications include high-side current sensing, 48 V telecom systems, power management, base stations, bidirectional motor control, and precision high-voltage current sources. - What is the supply voltage range for the AD8218BRMZ-R7?
The supply voltage range is from 4 V to 5.5 V. - Is the AD8218BRMZ-R7 RoHS compliant?
Yes, the AD8218BRMZ-R7 is RoHS compliant.
