TPS7A4525EVM-385

This user’s guide describes the characteristics, operation, and use of the TPS7A45xxEVM-385 evaluation module (EVM). This EVM demonstrates the Texas Instruments TPS7A45xx low-noise fast-transient-response 1.5-A low-dropout (LDO) voltage regulator. This user’s guide includes setup instructions, a schematic diagram, a bill of materials (BOM), and PCB layout drawings for the EVM.

1 Introduction

The TPS7A45xxEVM-385 helps designers evaluate the operation and performance of the TPS7A45xx dc/dc converter. This converter is a 1.5-A low-noise fast-transient-response regulator.

1.1 Related Documentation From Texas Instruments

TPS7A45xx 1.5-A Low-Noise Fast-Transient-Response Low-Dropout Regulator in 5DDPAK/TO-263 package data sheet (SLVS720 )

2 Setup

This section describes the jumpers and connectors on the EVM and how to properly connect, set up, and use the TPS7A45xxEVM-385.

2.1 Input/Output Connector Descriptions

2.1.1 J1– INPUT (4-Wire Power/Sense Option)

This is the positive input supply voltage. Twist the leads to the input supply and keep them as short as possible to minimize EMI transmission.

2.1.2 J3– IN_GND (4-Wire Power/Sense Option)

This is the return connection for the input power supply of the converter.

2.1.3 J2– OUTPUT (4-Wire Power/Sense Option)

This is the positive connection from the output. Connect this pin to the positive input of the load.

2.1.4 J4– OUT_GND (4-Wire Power/Sense Option)

This is the return connection for the output.

2.1.5 JP1–ENABLE

This jumper enables or disables the regulator. Connecting the shorting jumper between pins 1 and 2 (VIN and EN) enables the converter. Connecting the shorting jumper between pins 2 and 3 (EN and GND) disables the converter. Do not leave this pin floating.

2.1.6 JP2– MODE

This jumper sets the mode of the TPS7A45xx. Connecting the shorting jumper between pins 1 and 2 forces the TPS7A45xx into fixed-output mode. Use this setting with fixed-output devices only. Remove J8 shorting jumper for adjustable-output devices.

For adjustable-output devices, the output voltage may be selected using these equations: VOUT = 1.21 (1 + R2 / R1) + IADJ · R2 IADJ = 1.21 / R1 R1 < 4.17 kW

3 Operation

Connect the positive input power supply to J1. Connect the input power return (ground) to J3. The TPS7A45xx device has an absolute maximum input voltage of 20 V. The recommended maximum operating voltage is 20 V.

Connect the desired load between J2 and J4. The TPS7A45xx device can supply up to 1.5 A of output current.

Configure jumpers JP1 and JP2 as required. The functions of JP1 and JP2 are described in Section 2.1.5 and Section 2.1.6, respectively.

4 Test Results

The following figures show typical responses of the TPS7A45xx to line and load transients.