Texas Instruments LM63635CC5QDRRRQ1

Overview

LM63635CC5QDRRRQ1 from Texas Instruments is an AEC-Q100 Grade 1 qualified synchronous step-down DC/DC converter delivering fixed 5V output at up to 3.25A, operating from 3.5V to 36V input, with 2.1MHz switching frequency, 50ns minimum on-time, and 23µA quiescent current - designed for automotive infotainment power rails.

For engineers reviewing the LM63635CC5QDRRRQ1 datasheet, LM63635CC5QDRRRQ1 pinout, LM63635CC5QDRRRQ1 application, or LM63635CC5QDRRRQ1 equivalent, key selection considerations include its WSON-12 package thermal performance (R_θJC(bot) = 6.3°C/W), precision enable thresholds (VEN-H = 1.5V ±75mV), RESET flag timing (t_RISE-DELAY = 2–5ms), and spread-spectrum EMI compliance per CISPR 25.

Technical Context

The LM63635CC5QDRRRQ1 implements peak-current-mode control with automatic PFM/PWM mode transition, enabling high light-load efficiency while maintaining tight regulation. Its internal 5V LDO (V_CC = 4.75–5.25V) powers control circuitry and supports logic-level interface functions including SYNC/MODE pin programmability and open-drain RESET flag.

It integrates high-side (R_DS-ON-HS = 93mΩ) and low-side (R_DS-ON-LS = 61mΩ) MOSFETs, features hiccup-mode short-circuit protection (NOC = 128 cycles), thermal shutdown (T_SD = 155–175°C), and input UVLO with hysteresis (V_{UVLO_R} = 3.5V, V_{UVLO_F} = 2.6–3.0V).

Key Specifications

Pinout & Package

LM63635CC5QDRRRQ1 uses a 3.00mm × 3.00mm WSON-12 package with exposed thermal pad (DAP), optimized for automotive PCB space constraints and thermal management. The 12-pin layout includes dedicated power, analog, and ground terminals with no internal connections on pins 3, 8, and 11.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar step-down converter applications.

Compared with LM63635CA5QDRRRQ1, the LM63635CC5QDRRRQ1 offers smaller solution size and better high-frequency EMI performance; versus TPS62933-Q1, it provides built-in spread spectrum and superior thermal resistance in a smaller 12-pin WSON, though with slightly lower output accuracy.

Availability

LM63635CC5QDRRRQ1 is available at Aetrix Electronics and suitable for automotive infotainment, ADAS camera modules, digital instrument clusters, and body control units requiring stable component supply across extended temperature and lifecycle demands.

Supply support for LM63635CC5QDRRRQ1 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and automotive-grade power management solutions.

The LM63635C-Q1 product line delivers highly integrated, AEC-Q100-qualified buck converters targeting demanding automotive power rails where small size, low IQ, and EMI robustness are critical.

FAQ

What is the exact output voltage tolerance of the LM63635CC5QDRRRQ1 under full load and temperature range?

The LM63635CC5QDRRRQ1 delivers a fixed 5.0V output with ±1.5% regulation accuracy over input voltage (7V–30V), load (1A–3.25A), and junction temperature (–40°C to +150°C) in continuous conduction mode. This specification is verified per Section 6.8 of the datasheet and reflects worst-case deviation from nominal, not typical performance.

Does the LM63635CC5QDRRRQ1 support external frequency synchronization, and what are the timing requirements?

Yes, the LM63635CC5QDRRRQ1 supports external synchronization via the SYNC/MODE pin. It accepts TTL/CMOS-compatible clocks up to 2.2MHz with t_{ON_OFF-SYNC} ≤ 100ns for both ON and OFF times. The device locks to the external clock within one cycle and maintains phase alignment - critical for multi-rail systems requiring deterministic switching timing.

How does the RESET flag on the LM63635CC5QDRRRQ1 behave during startup and fault conditions?

The LM63635CC5QDRRRQ1 RESET pin is an open-drain output that remains low until V_OUT reaches 93–95% of regulation (V_RESET-LOW) and stays valid for ≥2ms (t_RISE-DELAY). It asserts low during thermal shutdown, overcurrent hiccup, and EN deactivation. With EN low, RESET remains functional down to VIN ≥1.2V, enabling reliable system reset sequencing.

What thermal performance can be expected from the LM63635CC5QDRRRQ1 in a standard 4-layer automotive PCB layout?

In a JEDEC-standard 4-layer board with 2oz copper and 1in² thermal pad connection, the LM63635CC5QDRRRQ1 achieves R_θJA = 47.4°C/W and R_θJC(bot) = 6.3°C/W. At 3.25A load and 25°C ambient, junction temperature rise is ~20°C above ambient - well within the 150°C max rating. Optimized layout with additional thermal vias further reduces θ_JA by 15–20%.

Is the LM63635CC5QDRRRQ1 pin-compatible with other members of the LM63635C-Q1 family, such as the 3.3V or 400kHz variants?

Yes, all LM63635C-Q1 variants - including LM63635CC5QDRRRQ1 (5V/2.1MHz), LM63635CC3QDRRRQ1 (3.3V/2.1MHz), LM63635CA5QDRRRQ1 (5V/400kHz), and LM63635CA3QDRRRQ1 (3.3V/400kHz) - share identical WSON-12 (DRR) package, pinout, and footprint. Only V_OUT and f_SW differ; no PCB redesign is required when selecting among them.