SNIU033 May   2019 TMP390

 

  1.   TMP390EVM User's Guide
    1.     Trademarks
    2. 1 Overview
      1. 1.1 TMP390EVM Kit Contents
    3. 2 EVM Hardware Overview and Operation
      1. 2.1 Power Input and Regulation
      2. 2.2 Perforated Breakout Board
      3. 2.3 Dual-Channel Resistor Programmable Trip Points
      4. 2.4 Manual Trip Test and Reset
      5. 2.5 Open-Drain Output
    4. 3 Board Layout
    5. 4 Schematic and Bill of Materials

2.1 Power Input and Regulation

Power is supplied from the USB connector, J2, with +5 V. This input can connect to the USB port of a laptop or desktop. The evaluation board does not require an external power supply, but one may be used if desired (such as when the breakout board is disconnected), so long as the voltage is within the maximum rated voltage of the TMP390.

USB power is used when J1 is shorted at pins 1-2 using a jumper. This connects +5 V to the LDO (low dropout regulator), providing a regulated output voltage of +3.3 V. If an external supply is required, then jumper J1 can be removed and power may be connected to pin 2 of J1. If an external supply is used, the input voltage can be from +2.2 V to +5.5 V. The input voltage can be measured at test pin TP1 (VDD). The LED, D2, will illuminate when power is good.