Motors & Drives Information

IR's Integrated HVIC Technology Enables Sophisticated Protection and Shrinks Size Compared to Opto-Coupler- or Transformer-Based Discrete Solutions

International Rectifier, IR(R)(NYSE:IRF), a world leader in power management technology, today introduced a series of high voltage IGBT control ICs with a sophisticated set of protection functions. In addition to these advanced functions, these devices feature high noise immunity with up to 30% fewer components in half the footprint compared to discrete opto-coupler- or transformer-based solutions. The series consists of 1200V and 600V gate driver ICs and current sense interface ICs for a variety of applications including inverterized motor drives, general-purpose inverter circuits, switch-mode power supplies (SMPS) and uninterruptible power supplies (UPS).

"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, over-current 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 line of driver ICs and sensor ICs fill this requirement, while reducing component count and simplifying circuits.

1200V HVICs for Industrial Applications

There are five 1200V gate drivers made with IR's HVIC technology.

The IR22381 is an analog, three-phase IGBT gate driver. With a deadtime of 0.5usec (micro-seconds), the device is ten times faster than comparable opto-coupler-based drivers. Also, the IR22381 minimizes temperature drift and changes in performance over time.

An integrated de-saturation feature provides for all modes of over-current protection, including ground fault, shoot-through and short to supply rails protection. Soft shutdown is initiated in the event of an over-current condition followed by the turn-off of all six outputs. A shutdown input is included to enable custom shutdown functions. The IR22381 includes programmable deadtime, and the output drivers have separate turn-on/turn-off pins with a two-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 40kSamples/second, suitable for up to 20kHz asymmetrical PWM modulation and maximum delay is less than 7.5usec @20kHz. A noise immune bi-directional level-shifting circuit is used to avoid false common mode dV/dt noise up to 50V/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 three-phase 380VAC circuits at up to 50A@80 degrees C. Unlike solutions using opto-couplers, 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 deadtime insertion. Their low quiescent current on the high-side enables economical and space-saving bootstrap supply topology. Fault feedback on IGBT de-saturation 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 de-saturation 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. Input and output pins are 3.3V CMOS-compatible to simplify microprocessor interfacing. Separate power and signal ground pins enable emitter shunt configurations to simplify low-side IGBT current sensing. These devices are housed in a SSOP-24 package.