Description
IR2177/IR2277 is a high voltage, high speed, single phase current sensor interface for AC motor drive applications. The current is sensed by an external shunt resistor. The IC converts the analog voltage into a time interval through a precise circuit that also performs a very good ripple rejection showing small group delay. The time interval is level shifted and given to the output both as a PWM signal (PO) and analog voltage (OUT). The analog voltage is proportional to the measured current and is ratio metric with respect to an externally provided voltage reference. The max throughput is 40 ksample/sec suitable for up to 20 kHz asymmetrical PWM modulation and max delay is <7.5 µsec (@20kHz). Also a fast over current signal is provided for IGBT protection.
FEATUREs
• Floating channel up to 600 V for IR2177 & 1200 V for IR2277
• Synchronous sampling measurement system
• High PWM noise (ripple) rejection capability
• Digital PWM output
• Fast Over Current detection
• Suitable for bootstrap power supplies
• Low sensing latency (<7.5 µsec @20kHz)
• Ratiometric analog output suitable for DSP A/D interface