Texas Instruments TPS54340QDDAQ1

Overview

TPS54340QDDAQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive-qualified 4.5–42 V input, 3.5-A synchronous step-down DC-DC converter with integrated 92-mΩ high-side MOSFET, Eco-mode™ pulse-skipping for light-load efficiency, and adjustable 100 kHz–2.5 MHz switching frequency. It delivers regulated output down to 0.8 V in vehicle accessories, ADAS power rails, and industrial 12/24-V systems.

For engineers reviewing the TPS54340QDDAQ1 datasheet, TPS54340QDDAQ1 pinout, TPS54340QDDAQ1 application, or TPS54340QDDAQ1 equivalent, key selection considerations include its 146-μA no-load quiescent current, internal soft-start timing (0.42–2.1 ms), BOOT-recharge FET enabling >99% duty cycle, thermal shutdown at 176°C, and RT/CLK pin synchronization capability.

Technical Context

The TPS54340QDDAQ1 implements constant-frequency peak-current-mode control with internal slope compensation to prevent subharmonic oscillation above 50% duty cycle. Its transconductance error amplifier (350 μA/V normal, 77 μA/V during soft-start) drives the COMP pin to regulate FB against a 0.8 V ±1% reference.

Switching is governed by an internal PLL tied to the RT/CLK pin-supporting either resistor-programmed frequency (100–2500 kHz) or external clock synchronization. Frequency foldback activates during start-up and overcurrent faults to maintain inductor current control, while overvoltage protection disables the high-side MOSFET if output exceeds 106% of setpoint.

Key Specifications

Pinout & Package

TPS54340QDDAQ1 is housed in an 8-pin thermally enhanced HSOP (DDA) package (4.89 mm × 3.90 mm) with exposed PowerPAD™ thermal pad (Pin 9) requiring direct PCB GND connection for thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM5164QDDAQ1, TPS54340QDDAQ1 delivers 2.3× more output current at same input range but consumes slightly higher quiescent current; versus TPS54540QDDAQ1, it offers identical feature set and layout compatibility at reduced cost and thermal load for ≤3.5-A applications.

Availability

TPS54340QDDAQ1 is available at Aetrix Electronics and suitable for automotive infotainment, ADAS camera power, and industrial 24-V field controllers requiring stable component supply under AEC-Q100 Grade 1 conditions.

Supply support for TPS54340QDDAQ1 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 ICs, with deep expertise in automotive-grade reliability and functional safety.

TPS54340QDDAQ1 belongs to TI's automotive-qualified DC-DC converter portfolio, designed specifically for robust, high-efficiency power conversion in demanding vehicle subsystems including body electronics, ADAS, and infotainment.

FAQ

What is the maximum output voltage achievable with TPS54340QDDAQ1?

The TPS54340QDDAQ1 supports output voltages up to 58.8 V, determined by the feedback resistor divider ratio and the 0.8 V internal reference. However, practical maximum is constrained by the 42-V input limit and duty-cycle ceiling-output cannot exceed VIN minus losses. For example, with VIN = 42 V and 92-mΩ R_DS(on), max regulated output is ~39 V at light load. Always verify loop stability and thermal limits at high V_OUT/I_OUT combinations.

Does TPS54340QDDAQ1 require an external bootstrap diode?

No, TPS54340QDDAQ1 integrates a bootstrap recharge FET, eliminating the need for an external bootstrap diode. A 0.1-μF X7R/X5R ceramic capacitor (10-V rating minimum) must be placed between BOOT and SW pins. This integration simplifies layout, reduces component count, and enables reliable operation at >99% duty cycle-critical for low-dropout applications like 5-V output from 5.8-V battery.

How does Eco-mode™ operate in TPS54340QDDAQ1, and what triggers entry/exit?

TPS54340QDDAQ1 enters Eco-mode™ when output voltage remains regulated and peak switch current falls below the pulse-skip threshold (corresponding to ~600 mV on COMP pin). In this mode, switching halts, COMP is clamped, and quiescent current drops to 146 μA. Exit occurs when output droop causes the error amplifier to lift COMP above 600 mV, restarting PWM. Entry point depends on inductor value-e.g., ~31 mA with 22 μH-and is not fixed load-current threshold.

Can TPS54340QDDAQ1 synchronize to an external clock, and what are the timing requirements?

Yes, TPS54340QDDAQ1 synchronizes to an external clock via the RT/CLK pin. When pulled above 1.55 V, the internal amplifier disables and RT/CLK becomes a high-impedance clock input. Minimum CLK pulse width is 15 ns; PLL lock time is 78 μs at 500 kHz. Synchronization range is 160–2300 kHz. This capability reduces EMI by aligning switching edges with system clocks-essential in noise-sensitive ADAS and infotainment designs.

What thermal derating guidance applies to TPS54340QDDAQ1 in HSOP-8 PowerPAD™ package?

With θ_JA = 42°C/W on standard board, TPS54340QDDAQ1 dissipates ~2.1 W before reaching 150°C junction limit at 25°C ambient. Derate linearly above 25°C: max power = (150 − T_A) / 42. For 85°C ambient, max continuous power drops to ~1.55 W-limiting 3.5-A output to ~12-V input or lower. Use 2+ oz copper, thermal vias under PowerPAD, and minimize trace resistance to achieve full 3.5-A rating at elevated temperatures.