My Inquiry
My Account
Texas Instruments LM43603AQPWPRQ1
- Part No.:
- LM43603AQPWPRQ1
- Manufacturer:
- Texas Instruments
- Package:
- 16-PowerTSSOP (0.173", 4.40mm Width)
- Datasheet:
-
LM43603AQPWPRQ1.pdf
- Description:
- IC REG BUCK ADJ 3A 16HTSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:6,688
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM43603AQPWPRQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive-qualified 3.5-V to 36-V input, 3-A synchronous step-down DC-DC converter in HTSSOP-16 package. It delivers 27-µA quiescent current in regulation, supports 200 kHz–2.2 MHz adjustable switching frequency, and integrates synchronous rectification, internal compensation, and power-good flag - enabling compact, high-efficiency point-of-load regulation in automotive infotainment and ADAS power rails.
For engineers reviewing the LM43603AQPWPRQ1 datasheet, LM43603AQPWPRQ1 pinout, LM43603AQPWPRQ1 application, or LM43603AQPWPRQ1 equivalent, key selection criteria include its 1.015-V ±0.013-V feedback reference accuracy over –40°C to +125°C, 4.1-ms internal soft-start, PFM/DCM light-load operation, EN precision UVLO (2.20 V ±0.22 V), and EN55022 Class B radiated EMI compliance without external filters.
Technical Context
The LM43603AQPWPRQ1 employs peak current mode control with cycle-by-cycle current limiting and internal slope compensation for stable loop response across wide VIN and load ranges. Its architecture integrates high-side (120 mΩ) and low-side (65 mΩ) MOSFETs, a dedicated BIAS pin for efficiency optimization, and SYNC input for external clock synchronization up to 2.2 MHz.
It features dual-mode operation: forced PWM at full load and automatic transition to discontinuous conduction mode (DCM) or pulse-frequency modulation (PFM) at light loads to maintain >85% efficiency down to 1 mA. The device includes thermal shutdown (160°C), hiccup-mode short-circuit protection, and precision enable with 290-mV hysteresis for robust system-level sequencing.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 3.5 V to 36 V - supports 12 V and 24 V automotive battery rails with 42 V absolute max tolerance. |
| Output Current | 3 A continuous - sufficient for powering microcontrollers, sensors, and interface ICs in automotive ECUs. |
| Feedback Reference | 1.015 V ±0.013 V (–40°C to +125°C) - enables <±1% output voltage accuracy with standard resistor dividers. |
| Quiescent Current | 27 µA in regulation - extends battery runtime in always-on vehicle modules like telematics and body controllers. |
| Switching Frequency | 200 kHz to 2.2 MHz (500 kHz default) - allows optimization of inductor size, EMI, and efficiency for space-constrained layouts. |
| Thermal Shutdown | 160°C shutdown / 150°C recovery - provides reliable overtemperature protection in sealed enclosures without derating. |
| EMI Compliance | Meets EN55022 Class B radiated emissions - reduces need for external shielding or ferrite beads in infotainment head units. |
Pinout & Package
LM43603AQPWPRQ1 is housed in a thermally enhanced 16-pin HTSSOP (PWP) package measuring 6.6 mm × 5.1 mm × 1.2 mm, with exposed thermal pad connected internally to AGND for PCB heat sinking.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| SW (1,2) | Power switch node | Connects to inductor; carries high di/dt switching current - requires short, low-inductance layout to minimize ringing. |
| CBOOT (3) | Bootstrap capacitor connection | Supplies gate drive for high-side FET; requires 470-nF ceramic capacitor between CBOOT and SW. |
| VCC (4) | Internal LDO output | Bypass with 1–10 µF capacitor to AGND; no external loading permitted - powers internal logic and gate drivers. |
| BIAS (5) | Optional LDO input | Tie to VOUT (if 3.3–28 V) or external 3.3/5 V rail to reduce power loss; never exceed VIN - improves light-load efficiency by ~5%. |
| SYNC (6) | External clock input | Accepts 200 kHz–2.2 MHz square wave; enables synchronized multi-rail systems and EMI spreading - terminate with 50 Ω to avoid reflections. |
| RT (7) | Frequency programming | Resistor to AGND sets switching frequency; open circuit = 500 kHz default - 1% tolerance resistors recommended for stable timing. |
| PGOOD (8) | Open-drain power-good flag | Asserts high when VOUT is within ±10% of target; requires 10–100 kΩ pullup to ≤12 V logic rail - used for processor reset sequencing. |
| FB (9) | Feedback sense input | High-impedance (≤65 nA leakage) node monitoring resistor divider midpoint - determines output voltage with 1.015-V reference. |
| AGND (10) | Analog ground reference | Reference for FB, EN, SS/TRK, and internal references - must be star-connected to PGND near device to avoid noise coupling. |
| SS/TRK (11) | Soft-start / tracking control | Capacitor to AGND extends soft-start time; external ramp enables output voltage tracking during power-up - prevents backfeeding in multi-rail systems. |
| EN (12) | Enable input | Logic-compatible input with 2.20 V rising threshold and 290-mV hysteresis - supports precise system-level UVLO and sequencing with resistor dividers. |
| VIN (13,14) | Main input supply | Dual pins reduce IR drop and improve thermal performance; connect directly to bulk capacitor with minimal trace length to PGND. |
| PGND (15,16) | Power ground return | Low-impedance return path for high-side and low-side FETs; must be tied to AGND and thermal pad on PCB - critical for EMI and thermal performance. |
| PAD | Exposed thermal pad | Internally connected to AGND; soldered to large copper pour for thermal dissipation - required for 3-A operation at 125°C ambient. |
Key Features
| Feature | Design Value |
|---|---|
| Automotive qualification | AEC-Q100 Grade 1 (–40°C to +125°C TJ) - certified for engine bay, front-end, and ADAS applications requiring long-term reliability. |
| Integrated synchronous FETs | 120 mΩ HS / 65 mΩ LS RDS(on) - eliminates external MOSFETs and drivers, reducing BOM count and footprint by >30% vs discrete solutions. |
| Light-load efficiency mode | Automatic DCM/PFM transition - maintains >85% efficiency at 1 mA load, critical for always-on vehicle subsystems. |
| Pre-biased soft-start | Supports startup into pre-charged output capacitors - prevents reverse current flow and protects downstream circuits during hot-plug events. |
| Output voltage tracking | SS/TRK pin accepts external ramp - enables coordinated power-up of multiple rails (e.g., core and I/O supplies) to meet FPGA or SoC sequencing requirements. |
| Robust protection suite | Thermal shutdown, hiccup-mode short-circuit, cycle-by-cycle current limit, and VCC UVLO - ensures safe operation under fault conditions without external supervision. |
Applications
| Automotive Infotainment Power | ADAS Camera Module Supply |
|---|---|
Use Scenario: Powers display controller, audio codec, and USB hub in head unit with 12 V battery input and strict EMI limits. IC Role / Device Role / Timing Role: Primary 3.3-V/5-V buck regulator providing clean, sequenced, and monitored power to digital subsystems. Use Value: EN55022 Class B compliance eliminates need for external EMI filters; PGOOD flag enables safe MCU boot sequence. |
Use Scenario: Supplies image sensor and ISP in rear-view or surround-view camera with cold-cranking tolerance. IC Role / Device Role / Timing Role: High-efficiency step-down converter delivering stable 1.8-V or 2.8-V rail from 9–16 V automotive input. Use Value: 3.5-V start-up capability supports operation during cranking dips; 27-µA IQ extends battery life in parked surveillance mode. |
| Industrial Telematics Gateway | Automotive Body Control Module |
Use Scenario: Provides regulated 5-V and 3.3-V rails for cellular modem, GNSS receiver, and CAN transceivers in fleet management units. IC Role / Device Role / Timing Role: Dual-output capable buck regulator (with external divider) serving as main system power manager. Use Value: Adjustable frequency (200 kHz–2.2 MHz) allows EMI tuning around cellular bands; SYNC input enables multi-rail coherence. |
Use Scenario: Powers microcontroller, LIN transceiver, and LED drivers in door module or lighting control unit. IC Role / Device Role / Timing Role: Compact, thermally efficient buck converter replacing discrete regulators in space-constrained modules. Use Value: HTSSOP-16 package with thermal pad enables 3-A output in <100 mm² area; BIAS pin optimization reduces thermal load by 15%. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar synchronous step-down converter applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM43602AQPWPRQ1 | 2-A output rating, identical pinout and feature set - lower current capacity but reduced thermal stress at 1.5–2 A loads. | Suitable for lower-power ECUs (e.g., mirror controls, seat modules) where 3-A headroom is unnecessary. | Select when thermal margin or cost optimization is prioritized over maximum output current headroom. |
| TPS54360BQDDAQ1 | 3.5–60 V input, 3.5-A output, external compensation - wider VIN range and higher current, but requires more external components and layout effort. | Better suited for 48-V mild-hybrid systems or designs needing >36 V input tolerance. | Choose when input voltage exceeds 36 V or when custom loop response tuning is required via external compensation. |
Compared with LM43602AQPWPRQ1 and TPS54360BQDDAQ1, the LM43603AQPWPRQ1 offers optimal balance of 3-A capability, integrated compensation, and automotive-grade EMI performance in a compact HTSSOP package - making it ideal for mainstream 12/24-V automotive power rails where board space and design simplicity are critical.
Availability
LM43603AQPWPRQ1 is available at Aetrix Electronics and suitable for automotive infotainment, ADAS camera modules, and industrial telematics requiring stable component supply, AEC-Q100 compliance, and long-term production continuity.
Supply support for LM43603AQPWPRQ1 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 power management technologies with decades of automotive qualification expertise.
The LM43603-Q1 family was designed specifically for demanding automotive power applications - delivering high efficiency, low EMI, and robust protection in compact packages for infotainment, ADAS, and body electronics.
FAQ
What is the minimum input voltage required for the LM43603AQPWPRQ1 to start switching?
The LM43603AQPWPRQ1 requires a minimum input voltage of 3.8 V to initiate switching, as specified in the datasheet's "Minimum input voltage for start-up" parameter (VIN-MIN-ST). This ensures reliable operation during automotive cold-crank events where battery voltage may dip to 6–7 V, while still maintaining regulation above 3.5 V nominal input. The device remains functional down to 3.5 V input but requires ≥3.8 V to exit UVLO and begin regulation. This behavior is consistent across all operating temperatures from –40°C to +125°C.
How does the BIAS pin improve efficiency in the LM43603AQPWPRQ1?
The BIAS pin on the LM43603AQPWPRQ1 allows connection to the output rail (for VOUT = 3.3–28 V) or an external 3.3/5 V supply, bypassing the internal VCC LDO and reducing power loss in the bias path. When enabled, it lowers operating quiescent current from 27 µA (VIN-powered) to ~13 µA (BIAS-powered), improving light-load efficiency by up to 5 percentage points. TI specifies that BIAS voltage must never exceed VIN, and the pin must not be left floating - grounding it disables the feature. This optimization is especially valuable in always-on automotive modules.
Can the LM43603AQPWPRQ1 be synchronized to an external clock, and what are the timing requirements?
Yes, the LM43603AQPWPRQ1 supports external clock synchronization via the SYNC pin, accepting frequencies from 200 kHz to 2.2 MHz with TTL/CMOS-compatible thresholds (0.4 V low, 2 V high). The sync signal must have a duty cycle between 10% and 90%, with minimum ON/OFF times of 80 ns each. Proper 50-Ω termination is required to prevent ringing. Synchronization enables EMI reduction through frequency alignment and coordinated multi-rail operation - critical in complex automotive systems where multiple converters share proximity on the PCB.
What is the purpose of the SS/TRK pin on the LM43603AQPWPRQ1, and how is it configured for tracking?
The SS/TRK pin on the LM43603AQPWPRQ1 serves dual functions: internal soft-start control (via external capacitor) and output voltage tracking (via external ramp voltage). For tracking, apply a voltage ramp (e.g., from another regulator's SS pin) to SS/TRK - the LM43603AQPWPRQ1's output follows this ramp with unity gain, enabling precise sequencing of multiple rails. This avoids backfeed and latch-up in FPGAs or processors requiring ordered power-up. Internal soft-start time is 4.1 ms with pin open; adding capacitance extends it linearly based on ISSC = 2 µA charge current.
Does the LM43603AQPWPRQ1 support operation into a pre-biased output capacitor?
Yes, the LM43603AQPWPRQ1 supports soft-start into a pre-biased output capacitor - a key requirement for hot-swap and redundant power systems. Its control architecture prevents reverse current flow during startup by disabling the low-side FET until the internal soft-start ramp exceeds the existing output voltage. This eliminates inrush current and potential damage to downstream components. The feature is enabled by default and requires no external configuration - verified across the full –40°C to +125°C temperature range and all supported output voltages from 1 V to 28 V.
LM43603AQPWPRQ1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- SIMPLE SWITCHER®
- Package/Case:
- 16-PowerTSSOP (0.173", 4.40mm Width)
- 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):
- 3.5V
- Voltage - Input (Max):
- 36V
- Voltage - Output (Min/Fixed):
- 1V
- Voltage - Output (Max):
- 28V
- Current - Output:
- 3A
- Frequency - Switching:
- 200kHz ~ 2.2MHz
- Synchronous Rectifier:
- Yes
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q100
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-HTSSOP
LM43603AQPWPRQ1 FAQ
1.How can I place an order for LM43603AQPWPRQ1 through Aetrix?
Please submit a Request for Quotation (RFQ) for LM43603AQPWPRQ1 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 LM43603AQPWPRQ1 reliable?
The price and inventory of LM43603AQPWPRQ1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM43603AQPWPRQ1 is usually 5 days.
3.What payment methods are accepted for LM43603AQPWPRQ1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM43603AQPWPRQ1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM43603AQPWPRQ1?
LM43603AQPWPRQ1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM43603AQPWPRQ1 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 LM43603AQPWPRQ1?
For technical support, including LM43603AQPWPRQ1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM43603AQPWPRQ1 requirements.
6.How does Aetrix verify that LM43603AQPWPRQ1 is sourced from the original manufacturer or authorized distributors?
All LM43603AQPWPRQ1 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 LM43603AQPWPRQ1 meets industry standards.
7.What is the process for return or replacement of LM43603AQPWPRQ1?
All LM43603AQPWPRQ1 units undergo pre-shipment inspection (PSI). If there is an issue with LM43603AQPWPRQ1, 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 LM43603AQPWPRQ1 part is unused and in its original packaging.
Return procedure for LM43603AQPWPRQ1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM43603AQPWPRQ1 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…
