IR22771SPBF Datasheet Summary

Overview

The IR22771SPBF is a high voltage, high speed, single phase current sensor interface designed for AC motor drive applications. It features a floating channel up to 600V, synchronous sampling measurement system, and high PWM noise rejection capability. The device is suitable for bootstrap power supplies and offers low sensing latency.

Features

• Floating Channel Voltage: Up to 600V
• Synchronous Sampling Measurement System: Ensures accurate current sensing
• High PWM Noise Rejection: Effective ripple rejection
• Digital PWM Output: Suitable for high-speed applications
• Fast Over Current Detection: Provides protection for IGBTs
• Low Sensing Latency: Less than 7.5 µsec at 20kHz PWM frequency
• Package Type: SOIC16WB

Electrical Characteristics

• Input Voltage Range: ±250mV
• Bootstrap Supply Range: 8-20V
• Quiescent Current: 2.2 mA (max) for floating channel
• Sensing Latency: Less than 7.5 µsec at 20kHz PWM frequency
• Throughput: 40 ksample/sec (max) at 20kHz PWM frequency
• Over Current Threshold: ±470 mV (max)

Absolute Maximum Ratings

• High Side Floating Supply Voltage (VB): -0.3 to 625V
• High Side Floating Ground Voltage (VS): VB - 25V to VB + 0.3V
• High-Side Input Voltages (Vin+/Vin-): VB - 5V to VB + 0.3V
• High-Side Range Selectors (G0/G1): VB - 0.3V to VB + 0.3V
• Low-Side Fixed Supply Voltage (VCC): -0.3 to 25V
• Synchronization Signal (Sync): -0.3V to VCC + 0.3V
• PWM Output (PO): -0.3V to VCC + 0.3V
• Over Current Output (OC): -0.3V to VCC + 0.3V
• Maximum Power Dissipation: 250 mW
• Thermal Resistance (RthJA): 90 °C/W
• Operating Junction Temperature (TJ): -40 to 125 °C
• Storage Temperature (TS): -55 to 150 °C

Recommended Operating Conditions

• High Side Floating Supply Voltage (VBS): VS + 8.0V to VS + 20V
• High Side Floating Ground Voltage (VS): -5V to 600V
• High-Side Input Voltages (Vin+/Vin-): VS - 5.0V to VS + 5.0V
• Low-Side Logic Fixed Supply Voltage (VCC): 8V to 20V
• Synchronization Signal Frequency (fsync): 4kHz to 20kHz
• Ambient Temperature (TA): -40 to 125 °C

Static Electrical Characteristics

• Quiescent VBS Supply Current (IQBS): 1 to 2.2 mA
• Quiescent VCC Supply Current (IQCC): 6 mA
• Offset Supply Leakage Current (ILK): 50 µA (max)
• Maximum Input Voltage Before Saturation (Vinmax): 250 mV
• Minimum Input Voltage Before Saturation (Vinmin): -250 mV
• Sync Input High Threshold (VIH): 2.2V
• Sync Input Low Threshold (VIL): 0.8V
• Sync Input Hysteresis (Vhy): 0.2V
• Over Current Activation Threshold (|Vocth|): 300 to 470 mV

AC Electrical Characteristics

• PWM Frequency (fsync): 4kHz to 20kHz
• Throughput (fout): 2 * fsync ksample/sec
• Bandwidth (BW): fsync kHz
• Group Delay (GD): 4 * fsync to 1 µs
• Minimum Duty Cycle (Dmin): 10%
• Maximum Duty Cycle (Dmax): 30%
• De-bounce Time of OC (tdOCon): 2.7 to 4.7 µs
• Time to Reset OC Forcing PO (TOCoff): 0.5 µs
• Measurement Delay (MD): 2 * fsync to 30 µs
• Step Response (SR): fsync to 51 µs

Pin Configuration

• 1: VCC (Low side voltage supply)
• 2: NC (No connection)
• 3: VSS (Low side ground supply)
• 4-5: NC (No connection)
• 6: OC (Over current signal, open drain)
• 7: PO (PWM output, open drain)
• 8: Sync (DSP synchronization signal)
• 9-10: NC (No connection)
• 11: G0 (Integrator gain lsb)
• 12: G1 (Integrator gain msb)
• 13: VS (High side return)
• 14: VIN- (Negative sense input)
• 15: VIN+ (Positive sense input)
• 16: VB (High side supply)

Functional Description

• SYNC Input: Clocks the whole device and must be synchronous with the triangular PWM carrier.
• PWM Output (PO): Open collector output (active low) that must be pulled up with an external resistor.
• Over Current Output (OC): Open drain output (active low) that triggers when the input voltage exceeds the threshold.
• DC Transfer Function: The PWM output duty cycle is inversely proportional to the input signal.
• Filter AC Characteristics: The signal path includes three stages, with the first two stages performing filtering actions to reject PWM noise.

Sizing Tips

• Bootstrap Supply: The VBS supply is floating and can be generated using a bootstrap method with a diode and capacitor.
• Bootstrap Capacitor Sizing: Consider factors such as quiescent current, leakage current, and charge required by internal level shifters.
• Bootstrap Diode: Should have a high breakdown voltage (BV) and fast recovery time (trr < 100 ns).