Texas Instruments TPS61120PW

Overview

TPS61120PW from Texas Instruments is a synchronous boost converter with integrated 200-mA LDO, designed for single-cell Li-Ion/Li-Polymer or multi-cell alkaline/NiMH battery-powered portable systems. It delivers adjustable DC-DC output (2.5–5.5 V) and adjustable LDO output (0.9–5.5 V), supports 1.8–5.5 V input, achieves 95% peak efficiency, and operates with 40-µA typical quiescent current - enabling long runtime in MP3 players, PDAs, and USB-powered handheld devices.

For engineers reviewing the TPS61120PW datasheet, TPS61120PW pinout, TPS61120PW application, or TPS61120PW equivalent, key selection considerations include dual-output configurability (boost + post-regulated LDO), low-battery detection (LBI/LBO), power-good signaling (PGOOD), thermal shutdown protection, and compatibility with compact 16-pin TSSOP packaging for space-constrained portable designs.

Technical Context

The TPS61120PW implements a fixed-frequency (400–600 kHz) PWM controller with multiple feed-forward compensation - monitoring V_IN, V_OUT, and NMOS switch voltage drop to dynamically adjust duty cycle without relying solely on slow error-amplifier feedback. Peak switch current is internally limited to 1300 mA (typ), and soft-start limits inrush during startup.

Its dual-ground architecture separates logic ground (GND) from power ground (PGND) to prevent noise coupling; the integrated antiringing switch clamps SW node ringing in discontinuous conduction mode, reducing EMI. The LDO stage is reverse-voltage protected, back-bias tolerant, and independently enabled via LDOEN - allowing flexible sourcing from boost output, battery, or external rails.

Key Specifications

Pinout & Package

TPS61120PW is housed in a 16-pin TSSOP package (5.00 mm × 4.40 mm body size) with exposed thermal pad not connected internally - suitable for standard reflow assembly and compatible with JEDEC MS-012AC footprint.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-output DC-DC + LDO applications.

Compared with TPS61121PW, the TPS61120PW offers full voltage adjustability at the cost of two external resistors; compared with TPS61222DRCR, it integrates LDO functionality but occupies larger board area - making TPS61120PW optimal for flexible, space-tolerant dual-rail portable designs.

Availability

TPS61120PW is available at Aetrix Electronics and suitable for MP3 players, PDAs, USB-powered medical sensors, industrial handheld scanners, and other portable electronics requiring stable dual-output power supply with battery longevity and seamless input source handling.

Supply support for TPS61120PW 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 over 50 years of innovation in energy-efficient power conversion solutions.

The TPS6112x product line was engineered specifically for portable battery-powered systems needing high-efficiency dual-rail generation from low-input sources - balancing integration, thermal performance, and design flexibility in compact packages.

FAQ

What is the minimum input voltage required for TPS61120PW to start up and regulate?

The TPS61120PW incorporates undervoltage lockout (UVLO) that prevents startup below approximately 1.6 V on VBAT. Stable regulation begins at 1.8 V input, supporting full discharge of single-cell Li-ion batteries down to 2.5 V and multi-cell alkaline/NiMH down to 1.8 V. Below 1.6 V, the device remains in shutdown with 0.2 µA current draw.

Can TPS61120PW generate two independent output voltages from separate input sources?

Yes. The TPS61120PW supports dual-input operation: the boost stage draws from VBAT, while the LDO can be supplied from LDOIN connected to an external source (e.g., USB 5 V or wall adapter). The LDO is reverse-voltage protected and back-bias tolerant, enabling seamless switchover without external diodes or OR-ing controllers.

How does the low-battery detection circuit function on TPS61120PW?

The TPS61120PW uses the LBI pin to monitor battery voltage via an external resistor divider. When the scaled voltage drops below 500 mV (±10 mV hysteresis), the open-drain LBO pin pulls low. This signal remains active only when EN = high; during shutdown, LBO is high-impedance. LBI must never float and should be tied to GND if unused.

What thermal considerations apply to TPS61120PW in TSSOP-16 package?

The TPS61120PW in TSSOP-16 has R_θJA = 100.5 °C/W. To maintain junction temperature ≤125°C at 85°C ambient, average power dissipation must stay below ~400 mW. Use ≥2 cm² of 2-oz copper connected to PGND/GND pins, avoid enclosing the IC, and ensure airflow if operating near maximum load (e.g., 500 mA at 5 V out from 1.8 V in).

Is TPS61120PW pin-compatible with other variants in the TPS6112x family?

Yes - all TPS6112x devices (TPS61120PW, TPS61121PW, TPS61122PW) share identical TSSOP-16 pinout and footprint. Functionally, they differ only in factory-set output voltages: TPS61120PW is fully adjustable (FB + LDOSENSE), while TPS61121PW and TPS61122PW have fixed outputs. No PCB redesign is needed when substituting within the family.