NXP Semiconductors TDA3629/N2,112

Overview

TDA3629/N2,112 from NXP Semiconductors (formerly Philips) is a monolithic light position controller IC designed for automotive headlight vertical beam elevation adjustment in passenger cars. It implements an on-off motor control strategy with hysteresis, delivers up to 670 mA output current at ≥12.3 V supply, features broken-wire and short-circuit detection on the SET input, and integrates thermal protection up to 160 °C junction temperature.

For engineers reviewing the TDA3629/N2,112 datasheet, TDA3629/N2,112 pinout, TDA3629/N2,112 application, or TDA3629/N2,112 equivalent, this page provides verified functional context, validated DIP8 package mapping, confirmed automotive-grade transient immunity (±150 V), and two documented alternative parts for headlight leveling systems requiring robust potentiometer-based feedback control.

Technical Context

The TDA3629/N2,112 operates as a closed-loop analog comparator system: it compares voltage from a dashboard-mounted setting potentiometer (SET) against voltage from a motor-coupled feedback potentiometer (FB), then drives dual H-bridge outputs (OUT1/OUT2) to rotate a DC motor until equilibrium is reached. Its on-off switching logic eliminates linear amplification losses and reduces noise sensitivity.

Internal protection includes under-voltage lockout (6–8 V), over-voltage shutdown (17.5–22.8 V), thermal foldback above ~160 °C, and dedicated SET-line fault detection-covering open-circuit (broken wire), short-to-battery, and short-to-ground conditions. All protections preserve brake function by short-circuiting the motor when active.

Key Specifications

Pinout & Package

Package: DIP8 (SOT97-1), plastic dual in-line, 300-mil width, through-hole mount. Thermal resistance: 100 K/W in free air.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TDA3629T, the TDA3629/N2,112 offers lower thermal resistance and simpler through-hole mounting; compared with UC2625N, it delivers complete analog servo functionality-including fault diagnostics and brake logic-in a single chip, reducing design risk and validation effort for automotive lighting systems.

Availability

TDA3629/N2,112 is available at Aetrix Electronics and suitable for automotive headlight leveling systems, OEM service replacement programs, and aftermarket lighting control modules requiring stable component supply across extended product lifecycles.

Supply support for TDA3629/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 company specializing in secure connectivity solutions for automotive, industrial, and IoT applications, with roots in Philips' semiconductor division.

The TDA3629/N2,112 belongs to NXP's legacy automotive analog controller family, engineered specifically for electromechanical headlight beam positioning-prioritizing functional safety, fault resilience, and direct potentiometer interface without software dependency.

FAQ

What is the primary function of the TDA3629/N2,112 in automotive systems?

The TDA3629/N2,112 serves as a dedicated analog light position controller that adjusts headlight beam elevation by comparing dashboard potentiometer (SET) and motor-coupled feedback potentiometer (FB) voltages, then driving dual H-bridge outputs to rotate a DC motor. It executes this function with built-in fault detection and thermal protection-no microcontroller or firmware required. The TDA3629/N2,112 is purpose-built for ECE R48-compliant headlight leveling in passenger cars.

Does the TDA3629/N2,112 support both 12 V and 24 V vehicle electrical systems?

The TDA3629/N2,112 is rated for 8–18 V operating supply, making it compatible with nominal 12 V automotive systems including cold-crank (down to 6 V under-voltage threshold) and load-dump transients (up to +100 V). It is not rated for 24 V systems-the absolute maximum non-operating voltage is +50 V, and over-voltage shutdown triggers at 17.5–22.8 V. For 24 V platforms, system-level voltage regulation to ≤18 V is mandatory before connecting the TDA3629/N2,112.

How does the TDA3629/N2,112 handle a broken wire on the SET input line?

The TDA3629/N2,112 includes dedicated broken-wire detection on the SET input: if the SET line opens, the internal circuit senses loss of pull-up bias and forces the motor into brake mode (OUT1/OUT2 shorted), preventing uncommanded beam movement. This behavior is confirmed in the Functional Description section and validated in Fig.6 test conditions. The TDA3629/N2,112 maintains this fail-safe state until the SET connection is restored and valid voltage reappears.

Can the TDA3629/N2,112 be used without external hysteresis components?

No-the TDA3629/N2,112 requires an external resistor (RSET) between SET and VP to set hysteresis level, as explicitly stated in the FEATURES list and CHARACTERISTICS table. Without RSET, the device lacks stable switching thresholds and may oscillate near setpoint. The datasheet specifies RSET > 2 kΩ and provides hysteresis tuning guidance in Fig.9 and Fig.10 application diagrams. Omitting RSET renders the TDA3629/N2,112 nonfunctional for closed-loop control.

Is the TDA3629/N2,112 pin-compatible with newer NXP automotive controllers?

No documented pin-compatible successors exist for the TDA3629/N2,112. While TDA3629T shares identical pin functions, it uses SO16 packaging with different physical layout and thermal characteristics. Modern NXP alternatives like the UJA1075 or SBC families are CAN-based system basis chips-not direct replacements-and require firmware, digital interfaces, and external motor drivers. The TDA3629/N2,112 remains a standalone analog solution with no drop-in upgrade path.