Texas Instruments UCC29411D

Overview

UCC29411D from Texas Instruments is a low-power synchronous boost converter IC optimized for single/dual alkaline battery operation, delivering 3.3 V at up to 200 mW from inputs as low as 0.8 V start-up and down to 0.5 V in operation. It integrates adaptive current-mode control, programmable reset timing via CT pin, and dual-output capability (main VOUT + auxiliary VGD). Used in battery-powered pagers and portable electronics requiring high efficiency across milliwatt-to-hundred-milliwatt loads.

For engineers reviewing the UCC29411D datasheet, UCC29411D pinout, UCC29411D application, or UCC29411D equivalent, key selection considerations include its 0.5 Ω charge switch R_DS(on), 1.2 Ω synchronous rectifier R_DS(on), 6 µA shutdown supply current, 3.3 V fixed output, and SOIC-8 package compatibility with space-constrained portable designs.

Technical Context

The UCC29411D employs bang-bang (hysteretic) control with multiplexed servicing of VOUT and VGD outputs, prioritizing VOUT unless VGD falls below 6.3 V. Its adaptive current-mode architecture transitions between discontinuous and continuous conduction modes based on load, enabling high efficiency from light to heavy loads.

Internal circuitry includes glitch-filtered reset generation (RESB), programmable reset period via external CT capacitor, anti-cross-conduction logic, and startup circuitry ensuring full-load operation at VIN ≥ 1 V. The SD/FB pin serves dual function: feedback input for adjustable versions (not applicable to UCC29411D) and shutdown control for all variants.

Key Specifications

Pinout & Package

UCC29411D is housed in an 8-pin SOIC (D) package, 3.94 mm × 4.90 mm × 1.75 mm, RoHS-compliant, MSL Level-2-260°C-1 year.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-input-voltage boost converter applications.

Compared with TLC59202D and TPS61200DRCR, UCC29411D uniquely combines guaranteed 1 V start-up, integrated 7 V VGD supply, and programmable open-drain RESB-making it optimal for compact, battery-critical systems where auxiliary rail and deterministic reset are essential.

Availability

UCC29411D is available at Aetrix Electronics and suitable for portable medical devices, wireless sensor nodes, handheld scanners, and industrial data loggers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for UCC29411D 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 low-power DC/DC conversion.

The UCC29411D belongs to TI's UCCx9411 family of ultra-low-voltage synchronous boost converters, designed specifically for maximizing battery life in single/dual-cell alkaline, NiCd, and NiMH-powered portable electronics.

FAQ

What is the guaranteed minimum input voltage for UCC29411D to start up under full load?

The UCC29411D guarantees startup under full 60 mA load at input voltages ≥1.0 V. This is ensured by design per the datasheet, enabling reliable operation even as alkaline batteries deplete. Once running, the device continues operation down to 0.5 V input. This behavior is specific to the UCC29411D and verified in electrical characteristics tables under "Minimum start-up voltage" test conditions.

Does UCC29411D require external feedback resistors to set its 3.3 V output?

No, UCC29411D provides a fixed 3.3 V output and does not require external feedback resistors. Unlike the adjustable UCC29411 variant (which uses SD/FB for feedback), the UCC29411D uses SD/FB exclusively for shutdown control. Its output regulation is internal and factory-trimmed, simplifying design and reducing BOM count. This fixed-output configuration is confirmed in the "available options" table and electrical characteristics section.

How is the reset timeout period programmed on UCC29411D?

The reset timeout period on UCC29411D is programmed using an external capacitor connected between the CT pin and GND. The relationship is t_RP = C × 1.25 seconds, where C is in farads. For example, a 0.15 µF capacitor yields a typical reset period of 188 ms. This timing controls the delay between VOUT rising above 90% of 3.3 V and RESB going high, ensuring stable microcontroller clock startup. The formula and typical values are specified in the RESET SECTION of the electrical characteristics table.

What is the function of the VGD pin on UCC29411D, and what load can it support?

The VGD pin on UCC29411D provides a coarsely regulated ~7 V auxiliary supply primarily for internal gate drive, but it can also power external circuitry. It supports up to 10 mA load as long as voltage remains above 2 V during startup. Below 6.3 V, VGD takes priority over VOUT in the multiplexing scheme. Its regulation range is 6.3–7.7 V, and it is explicitly characterized in the "VGD OUTPUT SECTION" of the electrical characteristics table.

Can UCC29411D operate from a single NiMH cell, and what efficiency can be expected at light loads?

Yes, UCC29411D supports NiMH input sources, with a specified input voltage range of 1.1–3.2 V and guaranteed operation down to 0.5 V. At light loads (e.g., 1–10 mA), efficiency exceeds 85% due to adaptive current-mode control minimizing switching and quiescent losses. Typical efficiency curves (Figures 6–11) show >87% at 10 mA with 1.2 V input and 22 µH inductor, confirming suitability for always-on sensor nodes.