Texas Instruments TPS61151DRCT

Overview

TPS61151DRCT from Texas Instruments is a dual-output, single-inductor boost WLED driver IC designed for independent current regulation of two white LED strings in portable displays. It operates from 2.5 V to 6 V input, delivers up to 27 V output per channel, integrates a 0.7-A N-channel MOSFET and built-in power diode, and supports PWM dimming up to 30 kHz - enabling high-efficiency backlight control in clamshell phones and dual-display handhelds.

For engineers reviewing the TPS61151DRCT datasheet, TPS61151DRCT pinout, TPS61151DRCT application, or TPS61151DRCT equivalent, key selection considerations include its 22-V overvoltage protection threshold, 10-μH inductor requirement, 330-mV IFB regulation voltage, and dual SEL-pin mode control for independent or simultaneous string enablement.

Technical Context

The TPS61151DRCT uses a fixed-frequency (1.2 MHz) current-mode PWM boost architecture with adaptive feedback headroom: it dynamically regulates the higher-voltage IFB pin (IFB1 or IFB2) to maintain 330 mV while allowing the other to float above regulation - minimizing power loss in mismatched LED strings. Its integrated 0.9-Ω rDS(on) MOSFET and 1-V forward-drop diode support up to 83% efficiency at typical loads.

Each output is controlled via dedicated SEL pins with internal 300–700 kΩ pulldown resistors, enabling shutdown (<1.5 μA), individual PWM dimming, or multiplexed operation. Overvoltage protection triggers at 22 V (typical) with 440 mV hysteresis, and thermal shutdown activates at 160°C with 15°C hysteresis - ensuring robust operation under fault conditions.

Key Specifications

Pinout & Package

TPS61151DRCT is housed in a 3.00 mm × 3.00 mm, 10-pin VSON package with exposed thermal pad for enhanced power dissipation (R_θJA = 44.3°C/W). The thermal pad must be soldered to analog ground with thermal vias for optimal junction temperature control.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-output WLED driver applications.

Compared with TPS61150DRCT, the TPS61151DRCT trades OVP margin for tighter voltage compliance in 22-V systems, while RT8532GQW adds configurability at the cost of integration - making TPS61151DRCT optimal for compact, cost-sensitive dual-backlight designs with defined 22-V ceiling.

Availability

TPS61151DRCT is available at Aetrix Electronics and suitable for clamshell phone backlighting, portable display modules, and keypad illumination systems requiring stable component supply, consistent parametric performance, and long-term production continuity.

Supply support for TPS61151DRCT 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 expertise in high-efficiency DC/DC conversion and LED driver innovation.

The TPS6115x product line was engineered specifically for space-constrained portable devices requiring dual independent WLED current regulation - prioritizing integration, thermal efficiency, and PWM dimming fidelity in ultra-small form factors.

FAQ

What is the overvoltage protection (OVP) threshold for TPS61151DRCT?

The TPS61151DRCT has a nominal overvoltage protection threshold of 22 V, with a typical hysteresis of 440 mV. This value is factory-trimmed and fixed per device variant - confirmed in Table 1 of the SLVS625E datasheet. It protects the internal 30-V MOSFET and ensures compatibility with standard 25-V output capacitors. The TPS61151DRCT OVP is lower than the 28-V threshold of the TPS61150DRCT, making it suitable for applications where strict 22-V ceiling compliance is required.

Can TPS61151DRCT drive mismatched LED strings with different forward voltages?

Yes, the TPS61151DRCT supports mismatched LED strings through its adaptive IFB regulation architecture. It dynamically regulates the higher-voltage IFB pin (IFB1 or IFB2) to 330 mV while allowing the other to float - maintaining accurate current in both strings despite forward-voltage differences up to ±150 mV. This behavior is explicitly described in Section 8.4.1 and validated in Figure 17 of the SLVS625E datasheet, where one string controls regulation during PWM dimming to suppress output ripple.

What is the recommended inductor value for TPS61151DRCT, and why?

The recommended inductor value for TPS61151DRCT is 10 μH, as specified in Section 7.3 and validated in the Typical Application (Figure 8) and Table 4. This value balances peak-to-peak ripple current (targeted at 30–40% of DC load), loop stability, and physical size. Using ±20% tolerance inductors is acceptable; however, values significantly outside 10 μH risk instability (larger L) or discontinuous conduction (smaller L), both degrading efficiency and regulation accuracy per Section 9.2.2.3.

How does PWM dimming work on TPS61151DRCT, and what is the maximum usable frequency?

PWM dimming on TPS61151DRCT is implemented via logic-level signals on SEL1 and SEL2: high enables the corresponding current sink, low disables it. The maximum usable frequency is 30 kHz, limited by the 6-μs current sink settle time (T_isink) and soft-start disable behavior during PWM. At 20% minimum duty cycle, Equation 4 in Section 9.2.2.2 confirms up to 33 kHz is feasible - placing noise above the audible range. This is verified in Figure 4 (dimming linearity) and Figure 6 (multiplexed waveform) of the datasheet.

Is TPS61151DRCT pin-compatible with TPS61150DRCT?

Yes, TPS61151DRCT is pin-compatible and package-compatible with TPS61150DRCT - both use the same 10-pin VSON (DRC) package with identical pin configuration, function mapping, and thermal pad layout. The only functional difference is the OVP threshold (22 V vs. 28 V), as documented in Table 1 of SLVS625E. No PCB changes are required for substitution; however, system-level validation of output voltage margin is recommended when swapping variants.