My Inquiry
My Account
Texas Instruments LM53635AQRNLRQ1
- Part No.:
- LM53635AQRNLRQ1
- Manufacturer:
- Texas Instruments
- Package:
- 22-PowerVFQFN
- Datasheet:
-
LM53635AQRNLRQ1.pdf
- Description:
- IC REG BUCK ADJ 3.5A 22VQFN
- Quantity:
- Payment:
- Shipping:
Inventory:2,835
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM53635AQRNLRQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive synchronous buck DC-DC converter delivering up to 3.5 A at adjustable output voltage, operating from 3.9 V to 36 V input with 2.1-MHz fixed switching frequency and ±1% output voltage accuracy over –40°C to +125°C junction temperature. It integrates high-side/low-side MOSFETs, internal compensation, soft-start, and thermal shutdown - used in automotive head units for stable 3.3-V or 5-V rail generation under transient surges.
For engineers reviewing the LM53635AQRNLRQ1 datasheet, LM53635AQRNLRQ1 pinout, LM53635AQRNLRQ1 application, or LM53635AQRNLRQ1 equivalent, key selection criteria include its 3.5-A continuous output capability, wettable-flank VQFN-22 package, spread-spectrum EMI reduction, external frequency synchronization (1.9–2.3 MHz), and integrated open-drain RESET with 3-ms release timer - all validated for automotive telematics and instrumentation cluster power rails.
Technical Context
The LM53635AQRNLRQ1 employs peak current-mode control with adaptive off-time extension to maintain regulation down to 300-mV dropout at 3.5 A, enabling operation with input as low as 3.55 V for 3.3-V output. Its flip-chip HotRod QFN architecture minimizes parasitic inductance, reducing switch-node ringing and radiated EMI without requiring external snubbers.
It supports seamless transition between forced PWM (via FPWM pin) and automatic light-load diode-emulation mode, achieving 15 µA typical quiescent current at no load (3.3-V output). The device includes built-in 0.6-V reference, 1.0-V feedback threshold, and a dedicated BIAS pin for efficiency optimization when connected to output rail.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Current | 3.5 A continuous - supports high-power automotive subsystems without external current boosting. |
| Input Voltage Range | 3.9 V to 36 V - accommodates cold-crank (≥3.55 V start-up) and load-dump transients up to 42 V (≤500 ms). |
| Switching Frequency | 2.1 MHz nominal - enables compact 2.2-µH inductors and avoids AM-band interference. |
| Output Voltage Accuracy | ±1% over –40°C to +125°C TJ - ensures reliable microcontroller and sensor rail stability across automotive ambient range. |
| Quiescent Current | 15 µA typical at no load (3.3-V output) - eliminates need for backup LDO in always-on domains. |
| RESET Output | Open-drain with 3-ms release timer and internal glitch filter (12–45 µs) - replaces discrete supervisor IC in safety-critical clusters. |
| Junction Temperature Range | –40°C to +150°C - qualified for under-hood placement per AEC-Q100 Grade 1 (–40°C to +125°C ambient). |
Pinout & Package
LM53635AQRNLRQ1 uses a 5.0-mm × 4.0-mm VQFN-HR (RNL) 22-pin package with wettable flanks for automated optical solder-joint inspection. Thermal performance is optimized via bottom-side PGND1/PGND2 pads and top-exposed thermal pad (connected to AGND).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VCC | Internal 3.1-V LDO output | Supplies internal control circuitry; requires 4.7-µF capacitor to AGND for stability. |
| CBOOT | Bootstrap capacitor node | Connects 470-nF capacitor to SW to drive high-side MOSFET gate above VIN. |
| SYNC | External clock input | Accepts 1.9–2.3 MHz system clock (rising-edge triggered); enables multi-rail synchronization. |
| PVIN1 / PVIN2 | Main power inputs | Dual VIN pins reduce IR drop and loop inductance; must be shorted on PCB with input capacitors. |
| SW | Switch node | Connects directly to power inductor; high dv/dt node requiring tight layout and ground shielding. |
| FB | Feedback input | Monitors output via resistor divider (for adjustable version); 1.0-V reference sets VOUT = 1.0 × (1 + R1/R2). |
| EN | Enable input | Active-high logic; 1.7–2.0 V threshold with 0.5 V hysteresis; supports direct connection to VIN. |
| RESET | Open-drain fault flag | Asserts low during UVLO, thermal shutdown, or EN deactivation; requires external pull-up. |
| FPWM | Forced PWM mode control | High = fixed 2.1-MHz operation; low = automatic light-load mode with diode emulation. |
| BIAS | Auxiliary bias supply input | Connected to output rail to improve light-load efficiency and reduce VCC LDO losses. |
Key Features
| Feature | Design Value |
|---|---|
| Integrated high-side/low-side MOSFETs | RDSON of 60–130 mΩ (HS) and 40–80 mΩ (LS) enables 3.5-A output without external switches or drivers. |
| Spread-spectrum modulation | ±3% frequency dithering reduces peak EMI by >10 dB, easing CISPR-25 Class 5 compliance in head units. |
| Low-dropout operation | Maintains regulation with only 300-mV VIN–VOUT differential at 3.5 A, supporting wide-input automotive systems. |
| Automotive-grade protection | Includes thermal shutdown (155–175°C trip), hiccup-mode short-circuit protection (6-ms wait), and UVLO with hysteresis. |
| Wettable-flank VQFN package | Enables AOI-compatible solder-joint inspection without X-ray, critical for zero-defect automotive manufacturing. |
Applications
| Telematics Control Unit | Automotive Head Unit |
|---|---|
Use Scenario: Powering LTE modem, GNSS receiver, and CAN gateway in vehicle infotainment systems with strict EMI limits. IC Role / Device Role / Timing Role: Primary 3.3-V/5-V buck regulator supplying processor I/O, memory, and RF front-end rails. Use Value: Spread-spectrum operation and low EMI switch-node waveform meet CISPR-25 Class 5 radiated emissions requirements without added filtering. |
Use Scenario: Generating stable 3.3-V and 5-V supplies for display controller, audio codec, and touch interface in digital dashboards. IC Role / Device Role / Timing Role: High-efficiency point-of-load regulator with RESET output monitoring system health for ASIL-B functional safety compliance. Use Value: Integrated RESET with 3-ms release timer and internal filtering eliminates external supervisor IC, saving board space and BOM cost. |
| Instrumentation Cluster | Battery Monitoring System |
Use Scenario: Supplying MCU, TFT LCD driver, and CAN transceiver in analog/digital gauge clusters exposed to under-hood temperatures. IC Role / Device Role / Timing Role: Automotive-qualified buck converter operating from 5–16 V battery with cold-crank support down to 3.55 V input. Use Value: Junction temperature rating up to +150°C and AEC-Q100 Grade 1 qualification ensure reliability in high-ambient environments. |
Use Scenario: Powering fuel-cell stack sensors, cell voltage monitors, and isolation amplifiers in 12-V/48-V hybrid battery management systems. IC Role / Device Role / Timing Role: Input-transient-tolerant regulator handling load-dump events up to 42 V for ≤500 ms without latch-off. Use Value: Absolute maximum VIN rating of 40 V with transient tolerance to 42 V simplifies input surge protection design and reduces TVS count. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar synchronous buck regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM53635MQRNLRQ1 | Includes spread-spectrum EMI reduction (±3%), while LM53635AQRNLRQ1 has fixed 2.1-MHz operation. | Suitable where radiated emissions compliance is critical (e.g., telematics modules near antennas); not required for shielded enclosures. | Select LM53635MQRNLRQ1 if CISPR-25 Class 5 testing shows marginal EMI margins; otherwise LM53635AQRNLRQ1 offers simpler timing analysis. |
| TPS54360BQDDAQ1 | Lower 3.5-A rating, 100-kHz to 2.5-MHz adjustable frequency, no integrated BIAS pin or wettable flanks. | Better for cost-sensitive non-telematics applications; lacks RESET output and automotive-specific thermal derating curves. | Choose TPS54360BQDDAQ1 only when footprint compatibility and lower BOM cost outweigh need for integrated RESET and AOI-friendly packaging. |
Compared with LM53635MQRNLRQ1 and TPS54360BQDDAQ1, LM53635AQRNLRQ1 provides superior EMI performance through optimized HotRod layout and wettable flanks for production traceability, while offering the most complete automotive feature set - including AEC-Q100 Grade 1 validation, integrated RESET, and BIAS-assisted efficiency - without requiring frequency tuning or external supervision.
Availability
LM53635AQRNLRQ1 is available at Aetrix Electronics and suitable for automotive telematics, head unit power management, and instrumentation cluster designs requiring stable component supply, long-term lifecycle support, and AEC-Q100-compliant sourcing.
Supply support for LM53635AQRNLRQ1 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 ICs, with decades of automotive qualification expertise and ISO/TS 16949-certified manufacturing.
LM53635AQRNLRQ1 belongs to TI's automotive-optimized DC-DC converter portfolio, designed specifically for high-reliability, low-EMI power conversion in head units, telematics, and instrument clusters operating across extended temperature and transient-voltage conditions.
FAQ
What is the minimum input voltage required for LM53635AQRNLRQ1 to start regulation?
The LM53635AQRNLRQ1 has a rising UVLO threshold of 3.2 V to 3.95 V, with typical startup at 3.55 V for 3.3-V output. This enables operation during automotive cold-crank events. Once started, it maintains regulation down to 300-mV dropout - meaning for a 3.3-V output, it sustains regulation with input as low as 3.6 V at full 3.5-A load. The exact value depends on junction temperature and output configuration; refer to Section 7.3 of the LM53635AQRNLRQ1 datasheet for test conditions.
Does LM53635AQRNLRQ1 support external frequency synchronization?
Yes, LM53635AQRNLRQ1 supports external frequency synchronization via the SYNC pin, which accepts a 1.9-MHz to 2.3-MHz square wave (rising-edge triggered). This allows precise timing alignment with other switching regulators in multi-rail automotive systems - critical for reducing beat-frequency noise in sensitive analog sections like audio codecs or camera ISPs. The LM53635AQRNLRQ1 maintains tight frequency lock across temperature and input voltage variations.
What is the purpose of the BIAS pin on LM53635AQRNLRQ1?
The BIAS pin on LM53635AQRNLRQ1 connects to the output voltage rail to power the internal VCC LDO more efficiently. When tied to VOUT, it reduces quiescent current and improves light-load efficiency by bypassing the internal charge pump. For a 3.3-V output, connecting BIAS to VOUT lowers IQ to 15 µA (typical); leaving it unconnected increases IQ to ~40 µA. This pin is mandatory for optimal performance in always-on automotive domains.
How does the RESET output of LM53635AQRNLRQ1 behave during startup and fault conditions?
The LM53635AQRNLRQ1 RESET output is an open-drain signal that goes low during EN deactivation, input UVLO, thermal shutdown, or output overvoltage. It features a built-in 3-ms release timer after fault clearance and a 12–45 µs internal glitch filter to reject noise. During normal startup, RESET asserts high only after the output reaches 90% of target voltage and remains stable - ensuring reliable power-good signaling for microcontrollers in automotive clusters without external RC delays.
Is LM53635AQRNLRQ1 pin-compatible with other devices in the LM536xx-Q1 family?
Yes, LM53635AQRNLRQ1 shares identical 22-pin VQFN-HR (RNL) package, pinout, and footprint with all LM53625/35-Q1 variants - including LM536353QRNLRQ1 (3.3-V fixed), LM536355QRNLRQ1 (5-V fixed), and LM53635MQRNLRQ1 (spread-spectrum). This enables single PCB design reuse across output voltage and EMI requirements. However, FB network values, BIAS connection, and FPWM/SYNC usage must be verified per variant per the LM53635AQRNLRQ1 application guidelines.
LM53635AQRNLRQ1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 22-PowerVFQFN
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Output Type:
- Adjustable
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 3.9V
- Voltage - Input (Max):
- 36V
- Voltage - Output (Min/Fixed):
- 3.3V
- Voltage - Output (Max):
- 10V
- Current - Output:
- 3.5A
- Frequency - Switching:
- 2.1MHz
- Synchronous Rectifier:
- Yes
- Operating Temperature:
- -40°C ~ 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q100
- Mounting Type:
- Surface Mount, Wettable Flank
- Supplier Device Package:
- 22-VQFN-HR (5x4)
LM53635AQRNLRQ1 FAQ
1.How can I place an order for LM53635AQRNLRQ1 through Aetrix?
Please submit a Request for Quotation (RFQ) for LM53635AQRNLRQ1 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for LM53635AQRNLRQ1 reliable?
The price and inventory of LM53635AQRNLRQ1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM53635AQRNLRQ1 is usually 5 days.
3.What payment methods are accepted for LM53635AQRNLRQ1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM53635AQRNLRQ1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM53635AQRNLRQ1?
LM53635AQRNLRQ1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM53635AQRNLRQ1 order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for LM53635AQRNLRQ1?
For technical support, including LM53635AQRNLRQ1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM53635AQRNLRQ1 requirements.
6.How does Aetrix verify that LM53635AQRNLRQ1 is sourced from the original manufacturer or authorized distributors?
All LM53635AQRNLRQ1 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that LM53635AQRNLRQ1 meets industry standards.
7.What is the process for return or replacement of LM53635AQRNLRQ1?
All LM53635AQRNLRQ1 units undergo pre-shipment inspection (PSI). If there is an issue with LM53635AQRNLRQ1, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The LM53635AQRNLRQ1 part is unused and in its original packaging.
Return procedure for LM53635AQRNLRQ1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM53635AQRNLRQ1 Tags
-
TPS562201DDCR
Texas Instruments
-
MC34063ABD-TR
STMicroelectronics
-
TPS561201DDCR
Texas Instruments
-
MC33063ADR
Texas Instruments
-
MC34063ADR
Texas Instruments
-
TPS560200DBVR
Texas Instruments
-
AP3012KTR-G1
Diodes Incorporated
-
TLV61048DBVR
Texas Instruments
-
AZ34063UMTR-G1
Diodes Incorporated
-
TPS562200DDCR
Texas Instruments
-
AP62300TWU-7
Diodes Incorporated
-
MC34063EBD-TR
STMicroelectronics
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
