Infineon Technologies IR2156STRPBF

Overview

IR2156STRPBF from Infineon Technologies is a ballast control IC integrating high-voltage half-bridge gate driver, programmable oscillator, and state-machine logic for fluorescent lamp electronic ballasts. It delivers programmable preheat frequency (49–60 kHz), run frequency (36–44 kHz), preheat time via CPH/RT/RPH, internal ignition ramp, and over-current threshold (1.1–1.44 V) with latch immunity. Used in 2D/4-pin CFL and T5/T8 linear lamp drivers.

For engineers reviewing the IR2156STRPBF datasheet, IR2156STRPBF pinout, IR2156STRPBF application, or IR2156STRPBF equivalent, key selection criteria include preheat timing control accuracy, high-side floating supply tolerance (VB up to 625 V), CT/CPH/RT programmability, CS fault response latency (160 ns), and SOIC-14 package thermal performance (RθJA = 82 °C/W).

Technical Context

The IR2156STRPBF implements a three-state lamp control sequence-PREHEAT → IGNITION RAMP → RUN-with automatic transition triggered by CPH voltage thresholds (7.5 V entry, 10 V exit, 13 V ramp completion). Its oscillator uses CT capacitor charging/discharging with dual thresholds (VCT+ = 8.3 V, VCT− = 4.8 V) and internal 3 kΩ dead-time resistor.

Protection logic includes UVLO (11.5 V turn-on, 9.5 V turn-off, 2 V hysteresis), shutdown pin threshold (5.1 V), over-current detection (1.25 V typ, 135 ns pulse width), and DC bus sensing via RVDC (10 kΩ typ) with VDC input. The VCC zener clamp (15.6 V) limits supply rail stress during transients.

Key Specifications

Pinout & Package

IR2156STRPBF is housed in a 14-lead SOIC (SOICN14) package with 1.27 mm pitch, rated for 1.40 W power dissipation at TA ≤ +25°C and RθJA = 82 °C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ballast control applications.

Compared with IRS2156DSPBF and IR2159SPBF, IR2156STRPBF offers optimized tape-and-reel delivery for high-volume SMT production, maintains lowest BOM count for dedicated ballast designs, and provides best-in-class preheat timing resolution via independent RT/RPH/CPH programming.

Availability

IR2156STRPBF is available at Aetrix Electronics and suitable for compact fluorescent lamp (CFL) ballasts, T5 linear fluorescent drivers, T8 dimmable ballasts, and lamp diagnostic modules requiring stable component supply and long-lifecycle support.

Supply support for IR2156STRPBF 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 ISO 9001 and IATF 16949.

The IR2156 product line targets energy-efficient fluorescent lamp ballast control, emphasizing integration, programmability, and robust fault handling for lighting OEMs transitioning from magnetic to electronic ballasts.

FAQ

What is the maximum allowable high-side floating supply voltage (VB) for IR2156STRPBF?

The absolute maximum VB rating is 625 V referenced to COM. Operation above this level risks permanent damage to the high-side driver stage. In practice, designs should maintain VB ≤ 600 V under worst-case transient conditions, as specified in Recommended Operating Conditions. The device's dV/dt immunity (50 V/ns) supports reliable operation in high-noise half-bridge environments.

How does the CPH pin control preheat duration and ignition ramp timing?

CPH is charged by a 4.3 µA internal current source through RPH. Preheat begins when CPH reaches 7.5 V, ends at 10 V (enabling RUN mode), and triggers ignition ramp at 13 V. The RPH value directly sets preheat time: e.g., 100 kΩ yields ~2.3 s to 10 V. During ramp, RPH is open, allowing CPH to rise further while fOSCRUN increases linearly from fOSCPH.

Can IR2156STRPBF operate without an external RT resistor?

No - RT is mandatory for preheat mode initialization. With RT open, the oscillator remains disabled and the IC stays in UVLO mode regardless of VCC or SD status. RT sets the preheat frequency base point; typical values range from 39 kΩ to 100 kΩ depending on lamp type and desired fOSCPH (49–60 kHz). Omitting RT prevents any lamp starting sequence.

What happens when the CS pin exceeds 1.25 V for longer than 135 ns?

The over-current protection circuit triggers a fault latch: HO and LO outputs disable immediately, CPH and CT discharge to 0 V, and quiescent current rises to ~180 µA in FAULT mode. Recovery requires cycling VCC below 9.5 V or pulling SD low to reset the latch. This behavior prevents MOSFET destruction during sustained short-circuit or lamp arc faults.