Texas Instruments TPS65268QRHBRQ1

Overview

TPS65268QRHBRQ1 from Texas Instruments is an AEC-Q100 Grade 1 automotive triple synchronous step-down converter delivering 3 A, 2 A, and 2 A output currents across three independent channels (BUCK1/BUCK2/BUCK3), with 4-V to 8-V input range, 0.6-V ±1% feedback reference, and adjustable 200 kHz–2.3 MHz switching frequency. It operates in forced continuous conduction mode (FCCM) for low output ripple and supports 180° out-of-phase BUCK1 timing versus in-phase BUCK2/BUCK3 to minimize input filter requirements in car audio and ADAS power rails.

For engineers reviewing the TPS65268QRHBRQ1 datasheet, TPS65268QRHBRQ1 pinout, TPS65268QRHBRQ1 application, or TPS65268QRHBRQ1 equivalent, this device serves as a monolithic, thermally robust, and ESD-hardened (HBM ±2 kV, CDM ±750 V) power management IC optimized for automotive infotainment, camera modules, and gateway ECUs requiring precise voltage sequencing, PGOOD supervision, and robust overtemperature/overcurrent protection.

Technical Context

The TPS65268QRHBRQ1 implements constant-frequency peak-current-mode control with dedicated COMP, FB, SS, EN, BST, and LX pins per buck channel-enabling independent loop compensation, soft-start programming, and UVLO adjustment. Its internal PLL synchronizes switching to external clocks via ROSC, while phase-shifted operation between BUCK1 and BUCK2/BUCK3 reduces RMS input current by up to 40% compared to in-phase operation.

Each channel integrates high-side (R_DS(on) = 110 mΩ for BUCK1; 149 mΩ for BUCK2/BUCK3) and low-side MOSFETs, bootstrap circuitry with VBST–VLX UVLO monitoring, and 100% duty-cycle capability. The V7V LDO (4.96–6.3 V output, 78–260 mA limit) supplies gate drivers and internal logic, eliminating need for external bias rails.

Key Specifications

Pinout & Package

TPS65268QRHBRQ1 is housed in a 5.00 mm × 5.00 mm RHB (VQFN-32) package with exposed thermal pad soldered to PCB for optimal thermal performance (R_θJB = 7.4°C/W). Pin functions are validated per TI SLVSE48C datasheet Rev C (May 2023).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS65268QRHBRQ1, the TPS65267QRHBRQ1 extends input range at the expense of efficiency below 8 V and lower current capability, while the MPQ4436-AEC1 trades automotive-grade integration (V7V LDO, ROSC sync, PGOOD) for broader input voltage coverage and lower unit cost in non-automotive contexts.

Availability

TPS65268QRHBRQ1 is available at Aetrix Electronics and suitable for automotive infotainment systems, ADAS camera modules, and gateway ECUs requiring stable component supply, AEC-Q100 compliance, and long-term production continuity.

Supply support for TPS65268QRHBRQ1 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 deep expertise in automotive-grade power management and functional safety solutions.

The TPS65268-Q1 product line delivers highly integrated, AEC-Q100 qualified triple buck converters designed specifically for automotive subsystems demanding high reliability, precise sequencing, and robust fault handling in harsh environments.

FAQ

What is the maximum allowable input voltage for TPS65268QRHBRQ1?

The absolute maximum input voltage for TPS65268QRHBRQ1 is 12 V on PVIN1/PVIN2/PVIN3 and VIN pins, but the recommended operating range is strictly 4 V to 8 V per AEC-Q100 specification. Exceeding 8 V continuously risks violating thermal and electrical stress limits defined in the datasheet, even if within absolute max ratings. For 12-V tolerant designs, consider TPS65267QRHBRQ1 instead.

Does TPS65268QRHBRQ1 support power sequencing between its three outputs?

Yes, TPS65268QRHBRQ1 supports precise power sequencing via independent SS1/SS2/SS3 pins. Each soft-start pin has an internal 5.2-µA current source, allowing external capacitor values to set individual ramp times. By selecting different C_SS values (e.g., 100 nF for BUCK1, 220 nF for BUCK2, 470 nF for BUCK3), designers achieve staggered startup with programmable delays-critical for SoC and FPGA power-up requirements.

How does the PGOOD pin behave during startup and fault conditions in TPS65268QRHBRQ1?

The PGOOD pin of TPS65268QRHBRQ1 is an open-drain output that remains low until all three buck outputs reach regulation (within ±5% of target) and complete their soft-start cycles. If any output falls outside regulation-due to overvoltage (>107.5% V_REF), undervoltage (<92.5% V_REF), or hiccup-mode overcurrent-the PGOOD pin is actively pulled low. It reasserts high only after all faults clear and regulation is restored.

Can TPS65268QRHBRQ1 operate with 100% duty cycle, and under what conditions?

Yes, TPS65268QRHBRQ1 supports 100% duty cycle operation as long as the bootstrap capacitor voltage (V_BST–V_LX) remains above the UVLO threshold of ~2.1 V. This condition is maintained during low-VIN operation (e.g., 4.2 V input regulating 3.3 V output) when the high-side FET must remain on continuously. The internal bootstrap UVLO circuit monitors V_BST–V_LX and forces LX low to recharge the BST capacitor if the threshold is breached.

What thermal metrics define the package-level cooling performance of TPS65268QRHBRQ1?

TPS65268QRHBRQ1 in the RHB (VQFN-32) package has R_θJA = 33.3°C/W (junction-to-ambient, JEDEC standard), R_θJB = 7.4°C/W (junction-to-board), and R_θJC(bot) = 2.1°C/W (junction-to-case bottom). These values assume proper PCB layout: 400 mm² copper pour under the exposed thermal pad, 4 thermal vias (0.3-mm diameter), and minimal trace resistance. Real-world board-level R_θJB typically achieves 8–10°C/W with standard 2-layer designs.