AP21X1A-EVM User Guide

General Description

The AP21X1A and AP21X1AD are integrated high-side power switches optimized for Universal Serial Bus (USB) and other hot-swap applications. The family of devices complies with USB 2.0 and is available with both polarities of Enable input. They offer current and thermal limiting and short circuit protection, as well as controlled rise time and undervoltage lockout functionality. A 7ms deglitch capability on the open-drain Flag output prevents false overcurrent reporting and does not require any external components.

Applications

• Consumer electronics - LCD TVs & monitors, game machines
• Communications - set-top-boxes, GPS, smartphones
• Computing - laptops, desktops, servers, printers, docking stations, HUBs

Key Features

• Single USB Port Power Switches with Output Discharge
• Overcurrent and Thermal Protection
• 0.8A accurate Current Limiting
• Fast Transient Response
• Reverse Current Blocking
• 90mΩ On-Resistance
• Input Voltage Range: 2.7V - 5.5V
• 0.6ms Typical Rise Time
• Very Low Shutdown Current: 1µA (max)
• Fault Report (FLG) with Blanking Time (7ms typ)
• ESD Protection: 4kV HBM, 300V MM
• Active High (ex. AP2191A/AP2191D) or Active Low (ex. AP2181A/AP2181D) Enable
• Ambient Temperature Range -40°C to +85°C
• SOT25, SO-8, MSOP-8EP (Exposed Pad), and U-DFN2018-6: Available in "Green" Molding Compound (No Br, Sb)
• Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
• Halogen and Antimony Free. "Green" Device (Note 3)
• 15kV ESD Protection per IEC 61000-4-2 (with external capacitance)
• UL Recognized, File Number E322375
• IEC60950-1 CB Scheme Certified

Notes

1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS), 2011/65/EU (RoHS 2) & 2015/863/EU (RoHS 3) compliant. See https://www.diodes.com/quality/lead-free/ for more information about Diodes Incorporated's definitions of Halogen- and Antimony-free, "Green" and Lead-free.
2. Halogen- and Antimony-free "Green" products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and <1000ppm antimony compounds.

Typical Applications Circuit

A typical application circuit schematic for the AP21X1A, illustrating the connection of a power supply (2.7V to 5.5V) to the device's input (IN), with input and output capacitors (10µF, 0.1µF), a current-limiting resistor (10kΩ), and connections for the Enable (EN) and Fault (FLG) pins. A load is connected to the output (OUT).

Recommended Operating Conditions

Ordering Information

Evaluation Board

Photographs and PCB layout diagrams of various AP21X1A-EVM evaluation boards. These visuals display the physical component placement and routing on both the top and bottom layers of the printed circuit boards for different device package types, including SOT25, SOP-8, MSOP-8EP, and U-DFN2018-6.

Quick Start Guide

1. Insert jumpers to configure the input capacitance and output capacitance as described in the Application Information sections of the device datasheet.
2. Place the Enable jumper in the enable position.
3. Connect a +5V power supply between the IN and GND terminals. Make sure the power supply is turned off.
4. Connect an adjustable current or resistive load to the OUT and GND terminals.
5. Turn on the power supply.
6. Increase the load current and observe that the load current will stop increasing after reaching certain level. That is an indication that the device is limiting the load current.
7. Use an oscilloscope or a voltage meter to check that the FLG pin becomes low when the current limit is reached.

Evaluation Board Schematic

Detailed circuit schematics for the AP21X1A-EVM evaluation boards. These diagrams illustrate the internal connections of the AP21X1A IC, associated passive components (capacitors, resistors), jumpers for configuration, and signal paths for input, output, enable, and fault reporting.

Bill Of Materials

Bill Of Materials for AP21X1AW-EVM

Bill Of Materials for AP21X1AMP-EVM

Bill Of Materials for AP21X1AFM-EVM

Bill Of Materials for AP21X1AS-EVM

Bill Of Materials for AP21X1AS/FM/W/MP-EVM

PCB Layout

Visual representations of the PCB top and bottom layers for various evaluation board models are provided in figures. These diagrams detail component placement, trace routing, and mounting hole locations.

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