Texas Instruments TPS61021ADSGT

Overview

TPS61021ADSGT from Texas Instruments is a synchronous 3-A boost converter IC designed for ultra-low-voltage battery-powered systems. It operates from 0.5 V to 4.4 V input, delivers up to 4.0 V output with ±2.5% reference accuracy, achieves 91% efficiency at 2.4 V_IN/3.3 V_OUT/1.5 A, and uses a 2-MHz switching frequency with PFM mode at light load - enabling extended runtime in single- or dual-cell alkaline/NiMH/Li-ion applications.

For engineers reviewing the TPS61021ADSGT datasheet, TPS61021ADSGT pinout, TPS61021ADSGT application, or TPS61021ADSGT equivalent, key selection criteria include its 0.5-V startup capability, true input-output disconnection during shutdown, 4.35-V overvoltage protection, thermal shutdown at 150°C, and compatibility with compact 2-mm × 2-mm WSON-8 packaging for space-constrained IoT and portable medical designs.

Technical Context

The TPS61021ADSGT implements adaptive constant-on-time valley current-mode control with internal loop compensation, supporting quasi-constant 2-MHz PWM operation above 1.5 V_IN and frequency foldback down to 1 MHz below 1.5 V_IN to maintain efficiency across wide input ranges. Its synchronous rectification uses integrated high-side (51 mΩ) and low-side (58 mΩ) MOSFETs with valley current limit sensing during off-time.

It features pass-through mode when V_IN > V_OUT, under-voltage lockout (0.9 V rising threshold), soft-start (~200 µs typical), and protection including output overvoltage (4.35 V), short-circuit limiting (<100 mA at V_OUT < 1 V), and thermal shutdown with 20°C hysteresis - all implemented without external components beyond feedback resistors, inductor, and capacitors.

Key Specifications

Pinout & Package

TPS61021ADSGT is housed in a thermally enhanced 2.0-mm × 2.0-mm WSON-8 package with exposed thermal pad (DSG). The package supports high-power density layouts and requires solder paste stencil design per TI SLOA197.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS61022DSGR and MAX77818EWL+T, the TPS61021ADSGT uniquely balances ultra-low 0.5-V start-up, 17-µA quiescent current, and compact 2-mm WSON packaging - making it the optimal choice for battery-run IoT edge nodes where runtime, size, and simplicity are prioritized over programmability or extreme current headroom.

Availability

TPS61021ADSGT is available at Aetrix Electronics and suitable for battery-powered IoT devices, portable medical equipment, and supercap backup systems requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for TPS61021ADSGT 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 digital signal technologies - with over 50 years of power management innovation.

The TPS61021A belongs to TI's ultra-low-voltage boost converter product line, engineered specifically for energy-constrained portable and industrial applications where battery depletion, thermal limits, and PCB area are critical constraints.

FAQ

What is the minimum input voltage required for TPS61021ADSGT to start switching?

The TPS61021ADSGT requires a minimum input voltage of 0.9 V to initiate startup (UVLO rising threshold). Once running, it sustains operation down to 0.5 V - confirmed in Section 6.3 of the SLVSDM0 datasheet. This dual-threshold behavior enables deep battery discharge utilization while preventing erratic startup at marginal voltages. The TPS61021ADSGT achieves this via internal hysteresis and adaptive control that maintains regulation even as VIN decays below 1.0 V.

Does TPS61021ADSGT support true load disconnect during shutdown?

Yes, the TPS61021ADSGT provides true disconnection between input and output during shutdown, as explicitly stated in the Features section of the SLVSDM0 datasheet. When EN is pulled low, both internal MOSFETs turn off and no DC path exists from VIN to VOUT - verified by ISD ≤3.0 µA shutdown current (Section 6.5). This eliminates reverse leakage that could drain batteries in always-connected systems, distinguishing it from basic boost ICs with body-diode conduction paths.

What is the recommended inductor value for TPS61021ADSGT in a 3.3-V/1.5-A application?

Texas Instruments recommends a 0.47-µH inductor for 3.3-V/1.5-A operation, as shown in the Figure 11 typical application circuit and Table 2 of the SLVSDM0 datasheet. Validated parts include Coilcraft XFL4015-471ME (4.0×4.0×1.5 mm, 8.36 mΩ DCR, 6.6-A saturation) and Würth 744383360047 (3.0×3.0×2.0 mm, 22 mΩ DCR, 8.0-A saturation). These values balance ripple current (<40% of average), transient response, and thermal performance - avoiding instability or excessive core loss observed with values outside the 0.33–1.0 µH range.

How does TPS61021ADSGT handle output overvoltage conditions?

The TPS61021ADSGT includes dedicated output overvoltage protection (OVP) that triggers at 4.35 V (typical), as specified in Section 6.5 Electrical Characteristics. When VOUT exceeds this threshold, the device halts switching and enters latch-off state until VOUT falls 0.1 V below threshold (4.25 V), then resumes regulation. This protects downstream 3.3-V logic and sensors from damage due to feedback resistor misconfiguration or transient surges - a hardware-level safeguard independent of control loop behavior.

Can TPS61021ADSGT operate with input voltages higher than the programmed output voltage?

Yes, the TPS61021ADSGT supports pass-through mode when VIN exceeds the regulated VOUT by >1%. Per Section 7.3.5, it disables switching and turns on the high-side PMOS FET, delivering VOUT ≈ VIN − (IOUT × R_DS(on) + IOUT × DCR_L). This reduces conduction loss and heat generation during high-input conditions - such as when a supercapacitor discharges from 4.5 V to 3.5 V while powering a 3.3-V rail - improving overall system efficiency without requiring external bypass circuitry.