AMC1200BDWVR [Texas Instruments]

Key Features

1. ±250mV Shunt-Optimized Input Range

The AMC1200BDWVR accepts a linear differential input signal from −250mV to +250mV, making it suitable for measuring the small voltage developed across a low-value current-shunt resistor.

Advantages:

• Supports bidirectional current measurement
• Reduces power dissipation in the shunt resistor
• Provides direct connection to common current-sensing shunts
• Suitable for high-side and phase-current measurement
• Helps preserve measurement accuracy at high current levels

2. Reinforced Silicon-Dioxide Isolation Barrier

The device uses a capacitive silicon-dioxide isolation barrier to electrically separate its input and output circuits. The AMC1200B version supports 4250VPEAK isolation voltage and 1200VPEAK maximum working insulation voltage.

Advantages:

• Protects low-voltage control electronics
• Breaks ground loops between high- and low-voltage domains
• Supports high-voltage industrial power systems
• Provides predictable long-term isolation performance
• Meets UL 1577 and VDE V 0884-10 isolation requirements

3. Fixed Gain of 8

The amplifier provides a factory-defined differential gain of 8V/V. A 250mV differential input therefore produces an approximately 2V differential output.

Advantages:

• Eliminates external gain-setting resistors
• Reduces gain errors caused by resistor tolerances
• Simplifies interface design
• Provides consistent performance between production units
• Produces an ADC-compatible differential signal

4. Precision Current Measurement

The AMC1200BDWVR combines maximum nonlinearity of 0.075%, maximum input offset voltage of 1.5mV, and maximum initial gain error of ±0.5%.

Advantages:

• Improves current-control accuracy
• Reduces torque ripple in motor-control systems
• Supports stable measurements across the industrial temperature range
• Minimizes calibration requirements
• Enables reliable overcurrent monitoring

5. Fully Differential Output

The device generates a differential analog output referenced to the low-voltage-side power supply. Differential signaling helps reject noise coupled equally into both output lines.

Advantages:

• Improves noise immunity
• Interfaces efficiently with differential ADC inputs
• Reduces sensitivity to output-side ground interference
• Supports accurate signal transmission in electrically noisy systems
• Simplifies isolated feedback implementation

6. 60kHz Minimum Signal Bandwidth

A minimum small-signal bandwidth of 60kHz, with approximately 100kHz typical performance, allows the amplifier to track rapidly changing current signals.

Advantages:

• Suitable for motor phase-current measurement
• Supports fast protection and control loops
• Captures switching-system current behavior
• Provides responsive overload detection
• Improves dynamic control performance

7. High Common-Mode Rejection and Transient Immunity

The AMC1200BDWVR provides 108dB DC common-mode rejection and minimum common-mode transient immunity of 10kV/µs.

Advantages:

• Maintains signal integrity during high-voltage switching
• Resists interference from fast power-transistor transitions
• Suitable for IGBT- and MOSFET-based power stages
• Reduces measurement errors in noisy industrial environments
• Improves stability of isolated control loops

8. Flexible Low-Side Power Supply

The high-voltage input side operates from 4.5V to 5.5V, while the low-voltage output side supports supplies from 2.7V to 5.5V.

Advantages:

• Supports 3.3V and 5V control systems
• Interfaces with modern microcontrollers and ADCs
• Reduces the need for additional level-conversion circuitry
• Allows independent power supplies across the isolation barrier
• Provides flexibility in mixed-voltage designs

Applications

Industrial Motor Control

• Motor phase-current measurement
• AC motor drives
• Brushless DC motor controllers
• Servo drives
• Variable-frequency drives
• Industrial motion-control equipment

Power Conversion Systems

• Industrial inverters
• Solar power inverters
• Uninterruptible power supplies
• Switch-mode power supplies
• Power-factor-correction systems
• High-voltage DC-to-DC converters

Isolated Current Monitoring

• High-side current sensing
• Low-side current sensing with galvanic isolation
• Bidirectional current measurement
• Overcurrent protection circuits
• Battery current monitoring
• Power-stage diagnostic systems

Industrial Measurement and Control

• Factory automation equipment
• Programmable logic controller interfaces
• Isolated analog feedback circuits
• High-voltage test equipment
• Industrial power monitoring
• Data-acquisition systems