Infineon Technologies IR2155

Overview

IR2155 from Infineon Technologies is a self-oscillating high-voltage half-bridge gate driver IC designed to control N-channel MOSFETs or IGBTs in high-side floating configurations up to 600 V. It integrates a programmable 555-style oscillator (19.4–20.6 kHz typical), matched propagation delays, 1.2 µs typical deadtime, ±210 mA / +420 mA output drive capability, and undervoltage lockout for VCC and VBS. It is used in offline SMPS half-bridge topologies such as AC-DC adapters and fluorescent lamp ballasts.

For engineers reviewing the IR2155 datasheet, IR2155 pinout, IR2155 application, or IR2155 equivalent, key selection considerations include its bootstrap-compatible floating channel, 600 V offset tolerance, micropower startup current (125 µA typ.), oscillator frequency set by RT/CT, and internal deadtime preventing shoot-through in resonant converters.

Technical Context

The IR2155 implements a monolithic high-voltage IC (HVIC) architecture with latch-immune CMOS logic, enabling direct operation at VS = +600 V relative to COM. Its front-end oscillator uses an RT/CT network with f = 1 / [1.4 × (RT + 150 Ω) × CT], supporting precise frequency tuning across 19–106 kHz. The output stage features matched HO/LO propagation delays and built-in 0.5–2.25 µs deadtime to prevent cross-conduction.

It employs dual undervoltage lockout (UVLO) circuits - one for VCC (7.7–9.2 V threshold, 400 mV hysteresis) and one for VBS (7.3–9.2 V, 400 mV hysteresis) - ensuring safe startup and fault recovery. The VCC supply is internally clamped at 15.6 V via a zener, requiring external high-impedance biasing rather than low-impedance DC sourcing.

Key Specifications

Pinout & Package

IR2155 is housed in an 8-lead PDIP package (0.3 inch width), with lead assignments optimized for high-voltage isolation and thermal dissipation in offline power applications. Pin numbering follows standard DIP convention (pin 1 = RT, pin 8 = COM).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar self-oscillating half-bridge driver applications.

Compared with IR2155, IR2153 and IR21531 offer higher drive capability and flexibility but require external timing and lack integrated oscillator functionality - making IR2155 uniquely suitable for cost-sensitive, self-contained half-bridge SMPS where minimal BOM count is prioritized.

Availability

IR2155 is available at Aetrix Electronics and suitable for fluorescent ballasts, offline AC-DC SMPS, induction heating inverters, and small UPS systems requiring stable component supply and long-term industrial availability.

Supply support for IR2155 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Infineon Technologies is a German semiconductor manufacturer specializing in power management, automotive, and industrial control ICs, with global manufacturing and quality certification to industrial standards.

The IR2155 belongs to Infineon's legacy HVIC gate driver product line, engineered specifically for cost-effective, self-contained half-bridge control in offline power conversion - emphasizing integration, reliability, and bootstrap compatibility over programmability.

FAQ

Can IR2155 drive both MOSFETs and IGBTs?

Yes, IR2155 is explicitly qualified to drive both N-channel power MOSFETs and IGBTs in half-bridge configurations. Its ±210 mA / +420 mA peak output current and 600 V offset rating meet gate drive requirements for devices up to ~50 A I_C (IGBT) or 100 A I_D (MOSFET) in typical 20–100 kHz applications, as confirmed in Infineon's application notes AN-978 and AN-1001.

What is the minimum recommended RT resistor value?

The minimum recommended RT is 5 kΩ, per Infineon's design guidelines. Lower values risk excessive current into the RT pin, potentially degrading oscillator stability or exceeding the ±5 mA absolute maximum RT output current rating. At RT = 5 kΩ and CT = 1 nF, f_OSC ≈ 100 kHz - near the upper limit of reliable operation.

Why does IR2155 require a high-impedance VCC supply?

Because IR2155 incorporates an internal 15.6 V zener clamp on VCC, it must be biased through a high-value resistor (e.g., 100–470 kΩ) from a higher voltage rail (e.g., rectified mains). A low-impedance DC source exceeding 15.6 V would cause excessive power dissipation in the clamp and potential thermal failure, as stated in the "Note 1" section of the datasheet.

Is IR2155 pin-compatible with IR2153 or IR21531?

No - IR2155 has an 8-pin PDIP layout with dedicated RT and CT pins for its internal oscillator, while IR2153/IR21531 replace CT with a shutdown (SD) pin and omit the oscillator function. Pin functions differ at RT, CT, and SD locations; PCB layout and schematic changes are required for substitution.