Texas Instruments TPS62321YEDT

Overview

TPS62321YEDT from Texas Instruments is a 500-mA, 3-MHz synchronous step-down DC-DC converter in Chip Scale Package (CSP-8), delivering fixed 1.5 V output with ±1.3% DC accuracy over –40°C to 85°C, 2.7–6 V input range, and 86 µA quiescent current-designed for space-constrained mobile phones and smart-phone power rails.

For engineers reviewing the TPS62321YEDT datasheet, TPS62321YEDT pinout, TPS62321YEDT application, or TPS62321YEDT equivalent, key selection criteria include its 35-ns minimum on-time, integrated active power-down sequencing, 100% duty cycle capability for low-dropout operation, and compatibility with 0.9–2.2 µH inductors and 4.7–10 µF ceramic output capacitors.

Technical Context

The TPS62321YEDT employs voltage-mode control with input voltage feed-forward for fast transient response, operating at a fixed 3-MHz switching frequency with automatic PFM/PWM mode transition based on load current. Its dual MOSFET current limiting-720 mA (P-MOS) and 600 mA (N-MOS)-ensures stable operation during start-up and light-load conditions.

It integrates a dedicated discharge resistor (30–50 Ω) for controlled power-down sequencing and supports external synchronization via the MODE/SYNC pin, enabling master-slave configuration across multiple converters without phase conflict. The device features thermal shutdown at 150°C with 20°C hysteresis and undervoltage lockout at 2.4 V.

Key Specifications

Pinout & Package

TPS62321YEDT is packaged in an 8-pin NanoFree™ Chip Scale Package (CSP-8), bottom-terminal layout with 0.5 mm pitch, optimized for minimal PCB footprint and thermal performance via direct die attach.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous step-down converter applications.

Compared with TPS62321YEDT, TPS62320YED offers design flexibility at the cost of added external components, while TPS62313YZD serves a distinct voltage domain-neither is pin-compatible replacement, but both share identical thermal and layout constraints in CSP-8 form factor.

Availability

TPS62321YEDT is available at Aetrix Electronics and suitable for cell phone power management, smart-phone baseband subsystems, and WLAN module design requiring stable component supply with guaranteed long-term manufacturability.

Supply support for TPS62321YEDT 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 IC design.

The TPS623xx family was engineered for ultra-compact, high-efficiency DC-DC conversion in battery-powered portable electronics-emphasizing minimal solution size, fast transient response, and seamless integration with modern mobile SoCs.

FAQ

What is the recommended inductor value for TPS62321YEDT in a typical 3.6 V to 1.5 V application?

The TPS62321YEDT is validated with 0.9 µH and 2.2 µH inductors. For optimal efficiency and transient response at 3.6 V input, TI recommends a 0.9 µH shielded power inductor (e.g., FDK MIPW3226 series) with ≥500 mA saturation current. Larger values reduce ripple but increase size and degrade light-load efficiency.

Does TPS62321YEDT support external synchronization, and what clock signal parameters are required?

Yes, TPS62321YEDT supports external synchronization via the MODE/SYNC pin. It accepts a 2.65–3.35 MHz square wave with 20–80% duty cycle. Synchronization forces fixed-frequency PWM operation and aligns the P-channel MOSFET turn-on edge to the falling edge of the external clock-enabling deterministic phase relationships in multi-rail systems.

How does the power-save mode operate in TPS62321YEDT, and what is the PFM/PWM transition current?

In power-save mode, TPS62321YEDT pulses intermittently when output voltage drops below –1.5% of nominal (1.4775 V). The PFM/PWM transition occurs near 10–20 mA depending on input voltage and inductor value, approximated by IPFM/PWM ≈ (VO × (VI − VO)) / (2 × L × fSW). At 3.6 V input and 0.9 µH inductor, transition is ~15 mA.

Can TPS62321YEDT be used with ceramic output capacitors, and what is the minimum recommended value?

Yes, TPS62321YEDT is fully compatible with X5R/X7R ceramic capacitors. TI specifies a minimum 4.7 µF output capacitance (e.g., 0805 4.7 µF/6.3 V) for stable operation and acceptable output ripple. Using ≥10 µF further improves load transient response and reduces peak-to-peak ripple to <25 mV under 400 mA steps.

What thermal considerations apply to TPS62321YEDT in CSP-8 package at 500 mA continuous load?

With θJA = 250°C/W (low-K board), TPS62321YEDT dissipates ~350 mW at 500 mA/1.5 V output and 3.6 V input, resulting in ~88°C junction rise above ambient. To maintain TJ < 125°C, limit ambient temperature to ≤37°C or enhance PCB copper area under the PowerPAD™ to reduce thermal resistance.