HVICs for Motion Control Take on Higher Voltages and Safety Features

International Rectifier (IR) has expanded its portfolio of high-voltage integrated circuits (HVICs) for motion control by introducing new gate driver ICs and current-sensing ICs with higher voltage ratings and greater functionality. The company is introducing 1200-V and 600-V gate drivers and current-sensing ICs that can be used in inverterized motor drives as well as general-purpose inverters, switched-mode power supplies and UPSs.

Although IR has previously introduced current-sensing ICs for these applications, the new parts are the first to offer ratings as high as 1200 V. And while the company already offers 1200-V rated gate drivers, the new versions integrate safety features that previously required the addition of external glue logic or some programming of the host system’s DSP.

“This new suite of gate driver and sensor ICs made with IR’s high-voltage IC technology enables small circuits with full protection, including ground fault protection, which was once available only in high-end systems. The new ICs blaze a new path for low-end industrial or servo drives as well as cost-competitive appliances,” said David Tam, vice president of IR’s Consumer and Industrial Group.

Power stages using IGBTs or MOSFETs must be protected from failures such as short circuits, overcurrent conditions and ground faults. In addition to protection circuits, the fault conditions must be detected, or sensed, in order to enable the protection functions. IR’s new driver ICs and sensor ICs fill this requirement, while reducing component count and simplifying circuits.

Among the new 1200-V ICs is the IR22381, an analog, 3-phase IGBT gate driver. With a dead time of 0.5 µs, the device is said to be 10 times faster than comparable optocoupler-based drivers. Also, the IR22381 minimizes temperature drift and changes in performance over time.

An integrated desaturation feature protects against all modes of overcurrent, including ground fault, shoot-through and short-to-supply rails. Soft shutdown is initiated in the event of an overcurrent condition followed by the turn-off of all six outputs. A shutdown input is included to enable custom shutdown functions. The IR22381 includes programmable dead time, and the output drivers have separate turn-on/turn-off pins with a 2-stage turn-on output to achieve the desired IGBT dv/dt switching level. Voltage feedback provides accurate measurements, and a bootstrap power supply eliminates an auxiliary power supply.

The IR2277 and IR22771 are high-speed, single-phase current-sense interface ICs with synchronous sampling for motor drive applications. The current is sensed through an external shunt resistor, which converts the analog voltage into a time interval through a precise dual ramp system. The time interval is level-shifted and provides digital PWM output suitable for DSP and analog-to-digital interfaces without additional logic circuits.

The maximum throughput is 40 ksamples/s and maximum delay is less than 7.5 µs at 20 kHz. A noise immune bidirectional level-shifting circuit is used to avoid false common mode dV/dt noise up to 50 V/ns. The IR2277 provides both analog and PWM output, while the IR22771 provides PWM output.

The IR2214 and IR22141 are designed to drive single half-bridge circuits in power switching applications as well as 3-phase 380-Vac circuits at up to 50 A at 80°C. Unlike solutions using optocouplers, the IR2214 and IR22141 gate drivers deliver stability during their lifetime and include parameter matching, such as propagation delay for high- and low-side channels as well as dead time insertion. Their low quiescent current on the high-side enables economical and space-saving bootstrap supply topology.

Fault feedback on IGBT desaturation is included which automatically shuts down the IGBT when used in multi-phase configurations. Desaturation detection for both sides as well as an internal biasing resistor are included in the IR2214, while an active desaturation diode bias is included in the IR22141. The IR2214 and IR22141 can be connected together via a dedicated pin to protect the drive system from phase-to-phase short circuits.

For appliance motor drives and a wide range of general-purpose inverter circuits, the 1200V HVICs are available in 600V versions. The IR21381 is an analog 3-phase driver, similar to the IR22381. The IR2177 and IR21771 are 600-V versions of the IR2277 and IR22771. Rounding out the set, the IR2114 and IR21141 are 600-V versions of the IR2214 and IR22141. The new IC model numbers are listed in Table 1 and Table 2 along with their package types and component descriptions. Available immediately, these parts are offered with the following unit pricing in quantities of 10,000:

• IR22381Q, $12.05
• IR2277S, IR22771S (analog output); $3.94
• IR2214SS, IR22141SS; $4.50
• IR21381Q, $10.50
• IR2177S, IR21771S (analog output); $2.56
• IR2114SS, IR21141SS; $3.90.