Texas Instruments LM5165YQDGSTQ1

Overview

LM5165YQDGSTQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive synchronous buck converter delivering up to 150 mA at fixed 3.3 V output, with 3 V–65 V input range, 10.5 µA no-load quiescent current, and integrated 2-Ω PMOS high-side and 1-Ω NMOS low-side switches. It enables compact, high-efficiency bias supplies in engine control units, ADAS camera modules, and infotainment power rails.

For engineers reviewing the LM5165YQDGSTQ1 datasheet, LM5165YQDGSTQ1 pinout, LM5165YQDGSTQ1 application, or LM5165YQDGSTQ1 equivalent, key selection criteria include ultra-low IQ for always-on systems, 100% duty-cycle capability for low-dropout operation, selectable PFM/COT control modes, AEC-Q100 qualification, and compatibility with 3.3-V fixed-output automotive designs requiring EN/PGOOD sequencing and thermal shutdown with hysteresis.

Technical Context

The LM5165YQDGSTQ1 implements a constant-on-time (COT) or pulse-frequency modulation (PFM) control architecture without loop compensation, using an internal 1.223-V ±1% reference and adaptive dead-time management between its integrated PMOS high-side and NMOS low-side switches. Its 100% duty-cycle support eliminates bootstrap capacitor requirements and enables operation down to VIN – VOUT < 100 mV.

It features precision enable with 1.212-V turn-on threshold and 68-mV hysteresis, programmable current limit via ILIM resistor (four discrete levels), and active slew-rate control to meet CISPR 22 Class B EMI limits. The device operates across –40°C to +150°C junction temperature with thermal shutdown at 170°C and 10°C hysteresis.

Key Specifications

Pinout & Package

LM5165YQDGSTQ1 is housed in a 10-pin VSON package (DRC) with 3.0 mm × 3.0 mm body size and 0.5-mm pin pitch, featuring an exposed thermal pad for enhanced PCB heat dissipation. The package is RoHS-compliant and optimized for automated assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck converter applications.

Compared with LM5164YQDGSRQ1 and TPS54202HDDCR, LM5165YQDGSTQ1 uniquely combines AEC-Q100 Grade 1 qualification, 150-mA output, 10.5-µA IQ, and fixed 3.3-V output in a 3-mm² VSON package-making it the optimal choice for space-constrained, battery-sensitive automotive bias rails where reliability and integration are critical.

Availability

LM5165YQDGSTQ1 is available at Aetrix Electronics and suitable for automotive engine control units, ADAS camera modules, and telematics control units requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for LM5165YQDGSTQ1 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 experience in high-reliability power management solutions.

The LM5165-Q1 product line delivers ultra-low-IQ, wide-input synchronous buck converters designed specifically for automotive subsystems requiring long-term battery hold-up, AEC-Q100 compliance, and minimal external components.

FAQ

What is the maximum output current capability of the LM5165YQDGSTQ1?

The LM5165YQDGSTQ1 delivers up to 150 mA of continuous DC output current in Constant On-Time (COT) mode and up to 100 mA in Pulse Frequency Modulation (PFM) mode. This rating assumes proper thermal management using the exposed pad and recommended PCB copper area per TI's layout guidelines. The actual achievable current depends on input voltage, ambient temperature, and inductor DCR-LM5165YQDGSTQ1 maintains regulation across its full –40°C to +150°C junction range.

Does the LM5165YQDGSTQ1 require external compensation components?

No, the LM5165YQDGSTQ1 does not require external loop compensation components in either PFM or COT operating mode. Its control architecture is inherently stable due to internal voltage feedforward (in COT) and hysteretic regulation (in PFM), eliminating the need for external RC networks or op-amps. This simplifies design, reduces BOM count, and improves reliability-LM5165YQDGSTQ1 achieves excellent line and load transient response without user-tuned compensation.

How is the current limit configured on the LM5165YQDGSTQ1?

The LM5165YQDGSTQ1 uses the ILIM pin to select one of four preset peak current limit thresholds: 48 mA, 100 mA, 155 mA, or 240 mA (typical values for VSON package). A resistor from ILIM to GND sets the level-e.g., 56.2 kΩ yields ~120 mA, while shorting ILIM to GND selects the maximum 240 mA limit. This allows optimization of inductor saturation current and ripple for specific load requirements-LM5165YQDGSTQ1's current limit is internally sensed and cycle-by-cycle controlled.

Can the LM5165YQDGSTQ1 operate with input voltage below the output voltage?

Yes, the LM5165YQDGSTQ1 supports 100% duty-cycle operation, enabling dropout voltages as low as 100 mV. When VIN drops near VOUT (e.g., 3.3 V input), the high-side PMOS remains fully enhanced, sustaining regulation without requiring a bootstrap capacitor. This behavior is critical during automotive cold-crank events where battery voltage falls to 3 V-LM5165YQDGSTQ1 continues regulating its 3.3-V output with no interruption or dropout.

Is the LM5165YQDGSTQ1 pin-compatible with other members of the LM5165-Q1 family?

Yes, LM5165YQDGSTQ1 shares identical pinout and package (10-pin VSON, DRC) with LM5165XQDGSTQ1 (5-V fixed) and LM5165QDGSRQ1 (adjustable), enabling drop-in replacement across output voltage variants. All share identical EN, PGOOD, ILIM, SS, RT, and thermal pad connections-only the FB/VOUT pin function differs (internal divider vs. external resistor network). Layout reuse is fully supported-LM5165YQDGSTQ1 requires no PCB changes when substituting for other VSON-packaged LM5165-Q1 variants.