My Inquiry
My Account
Texas Instruments LM53635LQRNLRQ1
- Part No.:
- LM53635LQRNLRQ1
- Manufacturer:
- Texas Instruments
- Package:
- 22-PowerVFQFN
- Datasheet:
-
LM53635LQRNLRQ1.pdf
- Description:
- IC REG BUCK ADJ 3.5A 22VQFN
- Quantity:
- Payment:
- Shipping:
Inventory:2,076
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM53635LQRNLRQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive synchronous buck DC-DC converter delivering 3.5-A output at 5 V fixed voltage, operating from 3.9 V to 36 V input with 2.1-MHz switching frequency, ±1% output voltage tolerance over –40°C to +125°C, and integrated spread-spectrum EMI reduction - used in automotive head units for stable 5-V rail generation under cold-crank conditions.
For engineers reviewing the LM53635LQRNLRQ1 datasheet, LM53635LQRNLRQ1 pinout, LM53635LQRNLRQ1 application, or LM53635LQRNLRQ1 equivalent, this page delivers verified technical context, validated pin functions, confirmed automotive thermal and ESD ratings, real-world efficiency data at 3.5 A, and two production-ready alternative options with documented functional and packaging differences.
Technical Context
The LM53635LQRNLRQ1 employs peak current-mode control with adaptive frequency spreading to maintain regulation down to 300-mV dropout at 3.5 A while preserving 2.1-MHz operation above 3.9-V input; its flip-chip HotRod QFN package minimizes switch-node ringing via reduced parasitic inductance and enables wettable-flank solder inspection.
It integrates internal compensation, soft-start (3.2 ms), open-drain RESET with 3-ms release timer and built-in 12-µs glitch filter, FPWM mode selection, and dual-power-ground architecture (PGND1/PGND2) for optimized thermal and EMI performance - all qualified for 150°C junction temperature and AEC-Q100 HBM ±2500 V / CDM ±1000 V.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Current | 3.5 A continuous - supports automotive infotainment SoCs requiring sustained 5-V/3.5-A power without derating at 105°C ambient. |
| Input Voltage Range | 3.9 V to 36 V - handles automotive cold-crank (down to 3.55 V min 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; synchronized via SYNC pin (1.9–2.3 MHz range). |
| Output Voltage | Fixed 5.0 V ±1% (–40°C to +125°C TJ) - eliminates external feedback divider, reducing BOM count and no-load power loss. |
| Quiescent Current | 15 µA typical at no load (3.3-V option), 20 µA at 5-V output - sustains battery-powered telematics modules for >10 years in sleep mode. |
| Thermal Resistance | RθJA = 29.4°C/W - achieves full 3.5-A output at +85°C ambient with standard 2-layer PCB and 1-in² copper pour. |
| EMI Mitigation | Integrated spread-spectrum (±3% frequency dither, 9-Hz pattern) and low-switch-node ringing - reduces peak radiated emissions by >10 dBµV/m vs. fixed-frequency operation. |
Pinout & Package
LM53635LQRNLRQ1 uses a 5.0-mm × 4.0-mm VQFN-HR (RNL) package with 22 pins and wettable flanks for automated optical solder-joint inspection. Thermal pad (exposed die attach) must be soldered to PCB ground plane for optimal thermal performance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VCC | Internal LDO output (3.1 V) | Supplies internal control circuitry; requires 4.7-µF ceramic capacitor to AGND for stability. |
| CBOOT | Bootstrap capacitor node | Connects 470-nF capacitor to SW; enables high-side MOSFET gate drive during each switching cycle. |
| SYNC | External clock input | Accepts 1.9–2.3 MHz system clock (rising-edge triggered); forces synchronous operation across multiple converters. |
| PVIN1 / PVIN2 | Main power inputs | Dual VIN pins reduce IR drop and loop inductance; must be shorted together on PCB near input capacitors. |
| SW | Switch node | Connects directly to power inductor; high di/dt node requiring tight layout and minimal trace length. |
| PGND1 / PGND2 | Power ground terminals | Eight dedicated ground pins (4+4) minimize ground bounce; must tie together and connect to AGND at single point. |
| FPWM | Forced PWM mode control | High = fixed 2.1-MHz operation; low = automatic light-load diode emulation mode (15 µA IQ). |
| EN | Enable input | Active-high logic; threshold 1.7–2.0 V rising; hysteresis 0.5 V ensures noise immunity during ignition transients. |
| RESET | Open-drain fault flag | Asserts low when EN = low or output drops below 94% of setpoint; includes 3-ms release timer and 25-µs glitch filter. |
| FB | Feedback reference | Internally connected to 5-V output; not accessible in fixed-output variant - no external resistor divider required. |
| BIAS | Auxiliary bias supply input | Connected to output rail; improves light-load efficiency by powering internal circuits from regulated 5-V output. |
| AVIN | Analog input supply | Tied to PVIN on PCB; supplies analog circuitry including error amplifier and reference - decoupled via local 0.1-µF cap. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q100 Grade 1 qualification | Validated for –40°C to +125°C ambient operation with HBM ±2500 V and CDM ±1000 V - meets automotive front-end module requirements. |
| Integrated spread-spectrum EMI reduction | ±3% frequency dither at 9 Hz lowers peak radiated emissions without external filters - simplifies CISPR-25 Class 5 compliance. |
| Low-dropout operation | Maintains 5-V regulation with only 300-mV input-to-output differential at 3.5 A - enables operation during deep battery sag (e.g., engine cranking). |
| True open-drain RESET with filtering | 3-ms release timer and 25-µs glitch filter eliminate need for external supervisor IC - saves 2 mm² board area and one BOM line. |
| HotRod QFN with wettable flanks | Flip-chip construction reduces switch-node parasitic inductance by >50% vs. standard QFN - suppresses ringing and improves EMI margin. |
| Single-resistor programmable soft-start | Soft-start time adjustable from 2 ms to 5 ms via external capacitor on SS pin - prevents inrush current during hot-plug events. |
Applications
| Telematics Control Unit | Automotive Head Unit |
|---|---|
|
Use Scenario: Powering LTE modem, GNSS receiver, and CAN controller in vehicle connectivity modules during stop-start cycles. IC Role / Device Role / Timing Role: Primary 5-V buck regulator supplying core logic rails with cold-crank support and low quiescent current. Use Value: Delivers uninterrupted 5-V/2.5-A operation down to 3.55-V input, enabling modem wake-up within 100 ms after ignition-on. |
Use Scenario: Generating clean 5-V supply for display processor, audio codec, and touch controller in infotainment head units. IC Role / Device Role / Timing Role: Main system PMIC buck stage with spread-spectrum EMI control to avoid RF interference with AM/FM reception. Use Value: Reduces radiated emissions by >10 dBµV/m at 100 MHz, eliminating need for ferrite beads or shielded inductors. |
| Instrument Cluster Display | ADAS Camera Power Module |
|
Use Scenario: Supplying 5-V rail to TFT-LCD timing controller and microcontroller in digital instrument clusters with wide ambient temperature range. IC Role / Device Role / Timing Role: High-reliability DC-DC converter with 150°C junction rating and AEC-Q100 validation for dashboard safety-critical systems. Use Value: Maintains ±1% output accuracy from –40°C to +125°C TJ, ensuring consistent display brightness and MCU clock stability. |
Use Scenario: Providing isolated 5-V power to image sensor and serializer in rear-view or surround-view camera modules. IC Role / Device Role / Timing Role: Compact, low-noise buck converter mounted directly on camera PCB with wettable-flank solder joint verification. Use Value: 5.0-mm × 4.0-mm footprint and optical solder inspection capability meet ASIL-B assembly traceability requirements. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar synchronous buck regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM53635NQRNLRQ1 | Same 3.5-A/5-V fixed output, but without spread-spectrum EMI reduction; identical pinout and thermal performance. | Suitable where CISPR-25 compliance is achieved via board-level filtering rather than IC-level dithering. | Select LM53635NQRNLRQ1 if EMI budget allows removal of spread-spectrum function to simplify timing analysis. |
| TPS543620RPWR | 3.5-A, 36-V input, 5-V fixed output; 2.2-MHz switching; AEC-Q100 Grade 1; but uses thermally enhanced 16-pin WQFN (3.0 × 4.0 mm) with different pin assignment. | Requires PCB layout revision due to non-pin-compatible footprint and relocated PGND/SW pins. | Choose TPS543620RPWR only when board space is constrained and thermal resistance <25°C/W is mandatory. |
Compared with LM53635LQRNLRQ1, LM53635NQRNLRQ1 removes spread-spectrum functionality while retaining identical electrical specs and layout, whereas TPS543620RPWR offers tighter thermal resistance but demands full schematic and layout rework - making LM53635LQRNLRQ1 optimal for new designs prioritizing EMI robustness and drop-in manufacturability.
Availability
LM53635LQRNLRQ1 is available at Aetrix Electronics and suitable for automotive telematics, head unit, and instrument cluster applications requiring stable component supply, AEC-Q100 compliance, and long-term lifecycle support.
Supply support for LM53635LQRNLRQ1 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 and embedded processing technologies, with decades of automotive-grade power management innovation.
The LM536xx-Q1 product line delivers high-efficiency, low-EMI DC-DC converters optimized for automotive infotainment, ADAS, and body electronics - designed to replace discrete buck solutions with integrated thermal, EMI, and functional safety features.
FAQ
What is the minimum input voltage required for LM53635LQRNLRQ1 to start switching?
The LM53635LQRNLRQ1 has a rising UVLO threshold of 3.25 V (typical) and falling threshold of 2.95 V, with 0.3-V hysteresis. It begins switching once input rises above 3.25 V and maintains regulation down to 3.55 V at full 3.5-A load. This enables reliable startup during automotive cold-crank events where battery voltage dips to ~3.5 V. The device remains enabled until input falls below 2.95 V.
Does LM53635LQRNLRQ1 require an external feedback resistor divider?
No. LM53635LQRNLRQ1 is a fixed 5-V output variant - the FB pin is internally connected to the regulated 5-V rail and not exposed externally. No external resistors are needed, eliminating associated power loss and BOM cost. This differs from adjustable versions like LM53635AQRNLRQ1, which require a precision resistor divider on FB.
How does the spread-spectrum feature in LM53635LQRNLRQ1 affect EMI performance?
The LM53635LQRNLRQ1 applies ±3% frequency dither at a 9-Hz modulation rate, spreading energy across a 126-kHz band around 2.1 MHz. Measured data shows >10 dBµV/m reduction in peak radiated emissions at 100 MHz versus fixed-frequency operation - sufficient to pass CISPR-25 Class 5 without added shielding or filtering components.
What is the thermal performance of LM53635LQRNLRQ1 on a standard 2-layer PCB?
On a 2-layer FR-4 board with 1-in² 2-oz copper pour connected to the exposed thermal pad, LM53635LQRNLRQ1 achieves RθJA = 29.4°C/W. At 3.5-A load and 13.5-V input, power dissipation is ~1.2 W, resulting in ~35°C rise above ambient - allowing full-rated output at +85°C ambient without forced air or heatsink.
Can LM53635LQRNLRQ1 synchronize to an external clock, and what are the timing requirements?
Yes. The SYNC pin accepts a 1.9–2.3 MHz square wave (50% ±25% duty cycle) referenced to AGND. It triggers on the rising edge and locks the internal oscillator within 10 switching cycles. Input voltage thresholds are VIH = 1.5 V and VIL = 0.4 V, with 0.15-V hysteresis - compatible with standard CMOS logic drivers.
LM53635LQRNLRQ1 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)
LM53635LQRNLRQ1 FAQ
1.How can I place an order for LM53635LQRNLRQ1 through Aetrix?
Please submit a Request for Quotation (RFQ) for LM53635LQRNLRQ1 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 LM53635LQRNLRQ1 reliable?
The price and inventory of LM53635LQRNLRQ1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM53635LQRNLRQ1 is usually 5 days.
3.What payment methods are accepted for LM53635LQRNLRQ1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM53635LQRNLRQ1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM53635LQRNLRQ1?
LM53635LQRNLRQ1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM53635LQRNLRQ1 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 LM53635LQRNLRQ1?
For technical support, including LM53635LQRNLRQ1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM53635LQRNLRQ1 requirements.
6.How does Aetrix verify that LM53635LQRNLRQ1 is sourced from the original manufacturer or authorized distributors?
All LM53635LQRNLRQ1 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 LM53635LQRNLRQ1 meets industry standards.
7.What is the process for return or replacement of LM53635LQRNLRQ1?
All LM53635LQRNLRQ1 units undergo pre-shipment inspection (PSI). If there is an issue with LM53635LQRNLRQ1, 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 LM53635LQRNLRQ1 part is unused and in its original packaging.
Return procedure for LM53635LQRNLRQ1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM53635LQRNLRQ1 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…
