Texas Instruments TPS61045ADRBT

Overview

TPS61045ADRBT from Texas Instruments is a digitally adjustable, high-frequency boost converter IC designed for LCD/OLED bias supply in portable displays. It operates from 1.8 V to 6 V input, delivers up to 28 V output, features true shutdown with 0.1 µA shutdown current, integrates 6-bit DAC-controlled feedback, and uses PFM peak-current control with 375 mA typical current limit.

For engineers reviewing the TPS61045ADRBT datasheet, TPS61045ADRBT pinout, TPS61045ADRBT application, or TPS61045ADRBT equivalent, key selection considerations include digital output voltage programming via CTRL pin timing, 1 MHz max switching frequency enabling compact 4.7 µH inductor use, 1.233 V internal reference accuracy, thermal shutdown at ~160°C, and VSON-8 package compatibility with space-constrained handheld PCB layouts.

Technical Context

The TPS61045ADRBT implements constant peak-current PFM control with 375 mA typical current limit and 6 µs maximum on-time, ensuring stable discontinuous conduction mode (DCM) operation across load and input variations. Its dual-function CTRL pin enables both device enable/disable and digital output voltage stepping via pulse-width-coded commands.

Internal architecture includes a 6-bit DAC (64 steps, 19.6 mV/step) driving the DO pin to modulate the external feedback divider, an integrated input switch (Q1) that disconnects VIN from the system during shutdown, and thermal shutdown protection triggered at ~160°C junction temperature.

Key Specifications

Pinout & Package

TPS61045ADRBT is housed in an 8-pin VSON (DRB) package measuring 3.00 mm × 3.00 mm with exposed thermal pad connected to PGND. The package supports high-density layout and efficient heat dissipation when thermally anchored to PCB ground plane.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS61045ADRBT, TPS61042DRBT removes digital adjustability but improves cost and simplicity for fixed-rail designs, while MAX17065ETA+ trades pulse-based CTRL for I²C configurability and higher resolution-making it preferable in microcontroller-rich environments where bus resources are available.

Availability

TPS61045ADRBT is available at Aetrix Electronics and suitable for smartphone LCD bias supply, OLED display power management, handheld medical display systems, and PDA backlight driver support requiring stable component supply and long-term production continuity.

Supply support for TPS61045ADRBT 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 over 50 years of innovation in energy-efficient power conversion solutions.

The TPS61045ADRBT belongs to TI's portable display power management product line, engineered specifically for ultra-low-power, digitally tunable bias generation in space-constrained handheld and wearable displays.

FAQ

What is the function of the CTRL pin on the TPS61045ADRBT?

The CTRL pin on the TPS61045ADRBT serves two distinct functions: device enable/disable and digital output voltage programming. Pulling CTRL high enables the device with soft-start; pulling it low for ≥560 µs initiates true shutdown (0.1 µA current). Pulses of 1–60 µs or 140–240 µs on CTRL increment or decrement the internal 6-bit DAC, adjusting output voltage in discrete steps. This dual role eliminates need for separate enable and programming signals in compact display systems.

How does the TPS61045ADRBT achieve high efficiency at light loads?

The TPS61045ADRBT achieves high efficiency at light loads (e.g., 1–10 mA) through its pulse frequency modulation (PFM) peak-current control architecture. Unlike PWM converters that maintain fixed frequency and vary duty cycle, PFM reduces switching frequency as load decreases - minimizing switching losses while maintaining regulation. Typical efficiency exceeds 70% at 1 mA and remains >80% up to 10 mA, validated across input voltages from 1.8 V to 6 V per Figure 1 and Figure 2 in the SLVS440C datasheet.

Can the TPS61045ADRBT operate without the digital interface enabled?

Yes, the TPS61045ADRBT can operate without the digital interface. When CTRL is held high continuously, the DO pin defaults to its center voltage (607 mV), setting a fixed mid-range output. Alternatively, the DO pin may be left open and the feedback network configured as a standard resistive divider (R1/R2 only), yielding a static output voltage determined solely by V_FB = 1.233 V. In this mode, the device functions identically to a conventional boost converter with no CTRL timing dependencies or DAC interaction required.

What is the recommended inductor value for the TPS61045ADRBT in a typical 18 V @ 10 mA application?

For a typical 18 V output at 10 mA load, Texas Instruments recommends a 4.7 µH shielded power inductor such as the Murata LQH32CN4R7M51 or Sumida CDRH3D16-4R7. This value balances switching frequency (~1 MHz at full load), efficiency (>82% at 5 V input), and solution size. Inductor saturation current must exceed 450 mA (max ILIM), and DCR should be minimized to preserve efficiency - values below 150 mΩ are preferred. Layout requires short, wide traces between L, SW, and PGND to reduce EMI and conduction loss.

Does the TPS61045ADRBT include thermal protection, and how does it behave?

Yes, the TPS61045ADRBT includes internal thermal shutdown protection that activates when junction temperature exceeds approximately 160°C. Upon triggering, both internal switches (Q1 and Q2) turn off, halting switching and disconnecting input from output. The device remains latched in shutdown until junction temperature falls below the hysteresis threshold (~140°C), at which point normal operation resumes automatically. This behavior is documented in Section 7.3.7 of the SLVS440C datasheet and protects against sustained overload, poor PCB thermal design, or ambient overheating without requiring external circuitry.