Infineon Technologies TDA38840AUMA1

Overview

TDA38840AUMA1 from Infineon is a fully integrated 40 A synchronous Buck regulator with OptiMOS™ power stages, operating from 4.3 V to 17 V (or 2.0 V–17 V with external VCC), featuring 0.6 V ±0.5% reference voltage, fast Constant On-Time (COT) control, and monotonic soft-start with four selectable times. It delivers high-efficiency point-of-load power for server VRMs, telecom POLs, and storage subsystems.

For engineers reviewing the TDA38840AUMA1 datasheet, TDA38840AUMA1 pinout, TDA38840AUMA1 application, or TDA38840AUMA1 equivalent, key selection criteria include input voltage flexibility (2.0–17 V), programmable switching frequency (600 kHz–2 MHz), thermally compensated OCP with four settings, FCCM/DEM mode selection, and pre-bias start-up capability in distributed power architectures.

Technical Context

The TDA38840AUMA1 implements a fast COT control architecture with adaptive on-time generation, enabling stable regulation with ceramic output capacitors and sub-100 ns load transient response. Its internal LDO powers gate drivers and logic, supporting single-supply operation or extended PVin range via external VCC biasing.

It integrates dual OptiMOS™ MOSFETs (high-side and low-side), bootstrap diode, and current-sense circuitry. Protection includes thermally compensated over-current detection with four user-selectable thresholds, pre-bias start-up, and open-drain Power Good with adjustable threshold via feedback divider.

Key Specifications

Pinout & Package

Package: 5 mm × 6 mm PQFN (37-pin, exposed thermal pad), halogen-free and RoHS2-compliant with exemption 7a.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck regulator applications.

Compared with MP8772GQ-Z and TPS546D24, the TDA38840AUMA1 uniquely combines full integration (bootstrap diode, LDO, dual FETs), pre-bias start-up, and thermally compensated OCP in a 5×6 mm package-making it optimal for space-constrained, high-reliability industrial POLs where analog simplicity and fault resilience are prioritized over digital configurability.

Availability

TDA38840AUMA1 is available at Aetrix Electronics and suitable for server VRMs, telecom POLs, and enterprise storage power delivery requiring stable component supply, long-term industrial qualification, and consistent thermal performance across –40 °C to +125 °C.

Supply support for TDA38840AUMA1 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

Infineon Technologies is a German semiconductor manufacturer specializing in power management, automotive, and industrial control ICs, with leadership in silicon and wide-bandgap power devices.

The TDA38840 belongs to Infineon's OptiMOS™ IPOL family-designed specifically for high-current, low-voltage point-of-load regulation in datacenter and communications infrastructure where integration, thermal robustness, and fast transient response are critical.

FAQ

What is the minimum recommended output capacitance for stable operation?

The TDA38840AUMA1 is optimized for ceramic output capacitors and requires ≥220 µF total effective capacitance with ≤5 mΩ ESR. Stability is maintained across the full 600 kHz–2 MHz frequency range without external compensation, provided the feedforward capacitor (Cff = 0.1 µF) is placed per Figure 3 in the datasheet and layout follows section 15 recommendations.

Can the TDA38840AUMA1 operate without an external VCC supply?

Yes. The device operates from a single PVin supply (4.3 V–17 V) using its internal LDO to power gate drivers and logic. When PVin drops below 4.3 V, an external VCC (2.0 V–5.5 V) must be supplied to VCC/LDO to extend input range - Vin is then shorted to VCC/LDO, sharing the same 10 µF decoupling capacitor.

How is over-current protection configured and what happens during a fault?

OCP is set by connecting a resistor from ILIM to AGND, selecting one of four thresholds (e.g., 45 A, 50 A, 55 A, 60 A). During over-current, the device enters hiccup mode after 20 ms delay: it shuts down, waits 10 ms, then attempts restart. Thermal compensation adjusts the trip point linearly with junction temperature to maintain consistent protection across operating range.

Is the TDA38840AUMA1 compatible with standard 5 mm × 6 mm QFN reflow profiles?

Yes. The PQFN package meets IPC/JEDEC J-STD-020D moisture sensitivity level 3 and is qualified for standard lead-free reflow profiles (peak 260 °C, 20–40 sec above 217 °C). The exposed thermal pad must be soldered to a solid copper thermal plane with ≥80% solder coverage and 6–8 vias to inner ground layers for reliable thermal performance at 40 A continuous load.