AP63301WU-7 - 3A, 32V Sync Buck Converter, TSOT-23-6 | Diodes Inc
MPN: AP63301WU-7 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.8 | $0.80 |
| 10 | $0.69 | $6.90 |
| 100 | $0.55 | $55.00 |
| 500 | $0.46 | $230.00 |
| 1,000 | $0.4 | $400.00 |
| 3,000 | $0.35 | $1,050.00 |
AP63301WU-7 Overview
A synchronous buck converter is a switched-mode power supply topology that uses pulse-width modulation (PWM) to regulate an output voltage lower than its input, while replacing the external Schottky diode with an internal low-side MOSFET for higher efficiency. AP63301WU-7 belongs to the hierarchy: synchronous buck converter -> buck converter -> step-down regulator -> switching regulator -> DC-DC converter -> power management IC -> semiconductor IC. This category is used wherever a board needs a low-voltage rail (e.g., 3.3 V, 5 V, 12 V) generated from a higher-voltage bus (e.g., 12 V, 24 V industrial supplies), with higher efficiency than a linear regulator.
Key differentiating features include an internal high-side 75 mΩ / low-side 40 mΩ MOSFET pair, peak current-mode control with internal compensation, a 1.18 V-typical enable input that can be connected directly to VIN for automatic startup, internal soft-start, and an EMI-optimized gate driver that helps meet CISPR 25 / CISPR 22 conducted-emissions limits without complex filtering. The AP63301WU-7 is the EMI-tuned version of the family, while its sibling AP63300WU-7 adds frequency spread spectrum.
Technically, the device operates at a fixed switching frequency, uses peak current-mode control for fast transient behavior and simple loop compensation, and provides cycle-by-cycle current limit, thermal shutdown, and over-voltage protection. The TSOT-23-6 package with an exposed thermal pad keeps junction-to-ambient resistance low enough for 3 A operation at moderate VIN-VOUT differentials without external heatsinking.
Typical applications include 12 V and 24 V industrial bus point-of-loads, USB-PD / Type-C charging rails, white goods and home appliance power, telecom 5 V/3.3 V auxiliary supplies, and FPGA/MCU core or I/O rails. Compared with linear regulators, AP63301WU-7 dramatically lowers the heat dissipated when stepping 24 V to 5 V at 3 A.
Designers should size the input capacitor for RMS current, select the output inductor for approximately 20-40% ripple, and follow the datasheet feedback-resistor table to program the output between 0.8 V and roughly VIN minus losses. This page synthesizes distributor pricing, drop-in TSOT-23-6 alternatives, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for AP63301WU-7 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with AP63301WU-7 (same form factor and footprint) — differing in Continuous Output Current, Package, Quiescent Current.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
AP63300WU-7
✅ Drop-In📋 Reference alternative (not in catalog)
AP63205WU-7
✅ Drop-In✓ In Stock
$0.2036 / Unit
View Datasheet →AP63210WU
✅ Drop-In📋 Reference alternative (not in catalog)
AP63301WU-7 Maximum Ratings & Electrical Characteristics
| Topology | Synchronous Buck (Step-Down) |
| Input Voltage Range | 3.8 V to 32 V |
| Output Voltage Range | 0.8 V to ~28 V (adjustable) |
| Continuous Output Current | 3 A |
| High-Side MOSFET | 75 mΩ (typ.) |
| Low-Side MOSFET | 40 mΩ (typ.) |
| Quiescent Current | 280 µA (typ., no load) |
| Control Mode | Peak Current-Mode PWM |
| Feedback Voltage Reference | 0.8 V (typ.) |
| Enable Threshold (Rising) | 1.18 V (typ.) |
| EMI Reduction | EMI-optimized gate driver (no FSS) |
| Soft-Start | Internal |
| Protections | OCP, OVP, UVLO, Thermal Shutdown |
| Operating Junction Temperature | -40 °C to +125 °C |
| Package | TSOT-23-6 (TSOT26) with exposed pad |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
AP63301WU-7 Pin Configuration
| Pin 1 | EN — Enable input (active high; tie to VIN for auto-startup; rising threshold typ. 1.18 V) |
| Pin 2 | GND — Power and analog ground return |
| Pin 3 | SW — Switch node - connection point of the internal high-side / low-side MOSFETs and external inductor |
| Pin 4 | VIN — Input supply voltage, 3.8 V to 32 V |
| Pin 5 | BST — Bootstrap pin for high-side gate driver; connect to SW via 100 nF bootstrap capacitor |
| Pin 6 | FB — Feedback input to internal error amplifier; connect to VOUT resistor divider (VREF = 0.8 V typ.) |
Typical Applications
AP63301WU-7 is suitable for 6 applications: 24V Industrial Bus Point-of-Load, USB-PD / Type-C Charging Rails, Home Appliance & White Goods Power, Telecom Auxiliary Supplies, FPGA / MCU Power Rails, Automotive Accessory Power (Non-Safety).
24V Industrial Bus Point-of-Load
The AP63301WU-7's 3.8 V to 32 V VIN window directly accepts the 24V industrial bus and steps it down to 3.3V, 5V, or 12V rails without a pre-regulator. With 3 A capability and a 75 mΩ/40 mΩ MOSFET pair, it delivers 3.3V at 3 A from 24V input with roughly 90% efficiency and under 1 W dissipation. Its EMI-optimized gate driver helps meet CISPR 11/22 Class B in PLC, sensor, and motor-drive subsystems without complex input filtering.
Recommended
USB-PD / Type-C Charging Rails
USB-PD chargers require a buck converter that can take a 5V to 20V bus and produce 5V, 9V, 15V, or 20V outputs at 2 A to 3 A. The AP63301WU-7's 32V VIN tolerance and 3 A IOUT deliver USB-PD 60W capability in a TSOT-23-6 footprint, ideal for compact travel adapters and Type-C docks. The internal compensation and peak current-mode control simplify the loop design, while OVP and OCP safeguard the cable and downstream device.
Recommended
Home Appliance & White Goods Power
White goods such as washing machines, refrigerators, and dishwashers run from rectified 12V or 24V rails and need 3.3V, 5V, and 12V subsystems at 1 A to 3 A. The AP63301WU-7's TSOT-23-6 package fits small control boards, and its -40 °C to +125 °C junction range handles appliance thermal stress. EMI-optimized switching passes CISPR 14-1 conducted emissions without a complex pi-filter on VIN.
Recommended
Telecom Auxiliary Supplies
Telecom 48V systems use intermediate 12V or 5V rails for fans, microcontrollers, and housekeeping circuitry. The AP63301WU-7 directly accepts a 24 V to 32 V telecom tap and produces 5 V at 3 A for fans and control logic. Synchronous rectification keeps efficiency high at the 32V-max VIN, while internal OVP/OCP protects downstream ASICs during transient bus events.
Recommended
FPGA / MCU Power Rails
Modern FPGAs and high-performance MCUs require low-voltage, high-current cores (e.g., 1.0V, 1.2V, 3.3V) generated from a 5V or 12V rail. The AP63301WU-7's 0.8V reference and 3 A capability easily power a 1.2V/2 A core or 3.3V/3 A I/O rail. Peak current-mode control with internal compensation delivers fast load-step behavior when the SoC wakes from sleep.
Recommended
Automotive Accessory Power (Non-Safety)
12V automotive rails see 6V cranking dips up to 18V load-dump transients. The AP63301WU-7's 32V absolute-maximum VIN tolerates load-dump, while its 3.8V minimum starts cleanly during cranking. The TSOT-23-6 footprint is well-suited to infotainment, ambient lighting, and accessory USB hubs. For safety-critical powertrain or ADAS rails, an AEC-Q100-qualified part is recommended instead.
Recommended
Recommended Products Summary
Engineering reference data for AP63301WU-7 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | AP63300WU-7 | AP63205WU-7 |
|---|---|---|---|
| Package | TSOT-23-6 | TSOT-23-6 - same | TSOT-23-6 - same |
| Brand | Diodes Incorporated | Diodes Incorporated | Diodes Incorporated |
| Input Voltage Range | 3.8 V to 32 V | 3.8 V to 32 V | 3.8 V to 18 V |
| Continuous Output Current | 3 A | 3 A | 2 A |
| AEC-Q100 Automotive Grade | No | No | No |
Key Differentiators
- EMI-optimized gate driver without FSS (vs AP63300WU-7)
- 3 A output current in TSOT-23-6 (vs AP63205WU-7)
- Wide 32V VIN for industrial and telecom (vs Generic 18V buck in TSOT-23-6)
Design Notes
Place the input ceramic capacitor (≥ 10 µF X7R) directly between VIN (pin 4) and GND (pin 2) using the shortest possible trace. Place the bootstrap capacitor (100 nF) between BST (pin 5) and SW (pin 3) using a short, wide trace. The feedback divider (R1 from VOUT to FB, R2 from FB to GND) must connect to a Kelvin point after the output capacitor to prevent load-regulation errors. The exposed pad (EP) under the TSOT-23-6 must be soldered to a continuous ground copper pour to achieve rated thermal performance.
Estimated: at VIN = 24 V, VOUT = 5 V, and IOUT = 3 A, power dissipation P = (VIN - VOUT) × IOUT × (1/η - 1) ≈ 1.0 W assuming 92% efficiency. With θJA ≈ 60 °C/W on a 4-layer 1 oz JEDEC PCB, the junction rises ~60 °C above ambient; at 25 °C ambient the junction reaches ~85 °C, well within the 125 °C limit. For continuous VIN ≥ 28 V at 3 A, increase copper area or reduce VIN-VOUT differential.
Do not leave the BST pin floating - the converter will not start. Do not load the SW node with anything other than the inductor. Do not program VOUT above approximately VIN - 1.5 V or the high-side MOSFET will not turn on long enough to regulate. When using EN, ensure the source can drive above the 1.18 V rising threshold; tying EN directly to VIN is allowed because EN is a high-voltage tolerant pin. Avoid placing the feedback trace near the SW trace to prevent noise injection into the FB node.
Compliance Information
RoHS and REACH compliant per Diodes Incorporated product page. Not AEC-Q100 qualified - choose an AEC-Q100 part for automotive safety applications. Halogen-free per JEDEC JS709.
