NXP Semiconductors TDA3629T/N2,112

Overview

TDA3629T/N2,112 from NXP Semiconductors (formerly Philips) is a monolithic light position controller IC designed for automotive headlight elevation control in passenger cars. It implements an on-off motor control strategy with hysteresis, supports dual supply inputs (VP1/VP2), delivers up to 670 mA output current at 12.3 V, and integrates broken-wire and short-circuit detection on the SET input for dashboard potentiometer interfaces.

For engineers reviewing the TDA3629T/N2,112 datasheet, TDA3629T/N2,112 pinout, TDA3629T/N2,112 application, or TDA3629T/N2,112 equivalent, this page provides verified functional context, SO16 package mapping, automotive-grade transient immunity data (±150 V), thermal protection behavior, and validated alternatives for headlight leveling systems requiring fail-safe motor actuation.

Technical Context

The TDA3629T/N2,112 uses a comparator-based feedback loop with externally set hysteresis to drive bidirectional DC motors via two complementary output stages (OUT1/OUT2). Its SET input monitors a dashboard potentiometer wiper voltage (1.5–0.95×VP), while FB senses mechanical feedback from a coupled potentiometer. The device operates only within 8–18 V supply range and disables outputs outside under-voltage (6–8 V) or over-voltage (17.5–22.8 V) thresholds.

Internal protection includes thermal shutdown (~160 °C), broken-wire detection (ΔVSET ≤ 160 mV), SET short-to-battery/ground fault response, and automotive transient suppression per ISO/DIS 11452-tolerating ±150 V pulses on VP with internal flip-flop state retention during transients.

Key Specifications

Pinout & Package

Package: SO16 plastic small outline package (SOT109-1), 16-pin, 3.9 mm body width, lead pitch 1.27 mm, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar light position controller applications.

Compared with LM1949N and TLE4207-2G, the TDA3629T/N2,112 delivers complete, self-contained headlight leveling functionality-including dual supply support, embedded fault diagnostics, and transient-hardened operation-in a single SO16 package, reducing system-level complexity and qualification burden.

Availability

TDA3629T/N2,112 is available at Aetrix Electronics and suitable for automotive lighting systems, headlight leveling modules, and OEM passenger car electronics requiring stable component supply across extended temperature and voltage ranges.

Supply support for TDA3629T/N2,112 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

NXP Semiconductors is a global semiconductor leader focused on automotive, industrial, and IoT applications, with deep heritage in automotive analog and power ICs inherited from Philips.

The TDA3629T/N2,112 belongs to NXP's legacy automotive analog controller family, specifically engineered for fail-safe, low-noise headlight beam positioning in passenger vehicles-prioritizing functional safety, EMC robustness, and long-term supply stability.

FAQ

What is the primary function of the TDA3629T/N2,112 in automotive systems?

The TDA3629T/N2,112 is a dedicated light position controller IC that regulates headlight beam elevation by comparing dashboard potentiometer (SET) and mechanical feedback (FB) voltages, then driving a bidirectional DC motor via OUT1/OUT2 outputs. Its core function is closed-loop, fail-safe positioning-ensuring accurate, stable, and safe headlight adjustment under varying vehicle load and road conditions. This function is intrinsic to the TDA3629T/N2,112 and confirmed in Philips' 1996 specification.

Does the TDA3629T/N2,112 support dual-headlight (left/right) control from a single potentiometer?

Yes, the TDA3629T/N2,112 supports stereo operation via its VP2 pin, enabling two devices to share one SET potentiometer while maintaining independent power domains. This configuration prevents cross-talk during faults-e.g., if one module loses battery connection, the other continues regulating. The TDA3629T/N2,112 datasheet explicitly describes this use case and specifies VP2 as a second supply input for such applications.

How does the TDA3629T/N2,112 detect and respond to a broken SET wire?

The TDA3629T/N2,112 detects broken SET ground via ∆VSET measurement: it compares the voltage on the SET line during normal operation (≈0.17×Vb) with the voltage when the ground wire is interrupted. If the difference falls below 160 mV, the device halts motor motion and activates the brake. This behavior is defined in the "Characteristics" table and Fig.6 of the TDA3629T/N2,112 datasheet and is integral to its safety design.

What automotive transient standards does the TDA3629T/N2,112 meet?

The TDA3629T/N2,112 meets ISO/DIS 11452 immunity requirements for narrowband electromagnetic disturbances and withstands worst-case battery-line transients per IEC 747-1: −150 V negative pulses and +100 V positive pulses (50 ms max, non-repetitive). These ratings are documented in the "Limiting Values" section and validated in Figs 7–8 and 18–19 of the TDA3629T/N2,112 datasheet.

Is thermal protection active during continuous motor operation in the TDA3629T/N2,112?

Yes, the TDA3629T/N2,112 incorporates thermal protection that activates at approximately 160 °C junction temperature, reducing motor current to limit dissipation. Under continuous operation at Tamb = 105 °C, the SO16 package's 105 K/W thermal resistance limits usable motor current to ~220 mA at 13 V-values derived from the "Thermal aspects" section and Table 1 in the TDA3629T/N2,112 datasheet.