SLAA486B January   2011  – June 2019 MSP430G2452

 

  1.   EKG-Based Heart-Rate Monitor Implementation Using the MSP430G2xx LaunchPad™ Development Kit
    1.     Trademarks
    2. 1 Introduction
    3. 2 Hardware Description
      1. 2.1 Hand Detection Circuit
      2. 2.2 Analog Front End (AFE)
      3. 2.3 Pin Functionality Mapping on the LaunchPad Kit
      4. 2.4 eZ430 RF Target Header
      5. 2.5 Power Supply Setup
    4. 3 Software
    5. 4 References
  2.   A Amplifier Options
    1.     A.1 Instrumentation Amplifier Options
    2.     A.2 Operational Amplifier Options
  3.   B Wired USB Demo With Back-Channel UART
  4.   C Wireless UART Demo With the eZ430 RF Target Board
  5.   D Hardware Schematic Diagrams
  6.   Revision History

2.5 Power Supply Setup

With the daughterboard attached to the LaunchPad kit, there are multiple ways of powering up the system.

NOTE

The system is designed to be powered from only one power source at a time. The system should be powered from either USB or coin-cell or 2x AA or 2x AAA batteries.

USB Power

  1. Populate all of the jumpers on the LaunchPad kit (VCC, RXD, TXD, TEST, RST).
  2. Remove the jumper JP1 on the daughterboard.
  3. Connect the micro-USB cable from the LaunchPad kit to the PC. The 5 V from USB supply goes through a 3.3 V LDO and powers the whole system. The USB cable also serves as an application UART connection between the PC and the LaunchPad kit [4].

WARNING

When powering the system from USB, disconnect all batteries (coin-cell or 2x AA/AAA) connected to the system. If any battery remains plugged in, there is a risk of the battery being charged that could lead to an explosion, which causes potential for property damage, personal injury or death.

External Battery Power

  1. Remove all LaunchPad kit jumpers (VCC, RXD, TXD, TEST, RST).
  2. Populate the jumper JP1 on the daughterboard.
  3. Plug in the battery to connector B1 to power the system from one 3-V CR2032 coin-cell battery or plug in the connector to header B2 to power the system from two AA or AAA batteries.

WARNING

When powering the system from batteries, either the coin-cell or the 2 AA or AAA batteries connector should be plugged in. If both are connected together, there is a risk of one battery charging other that could lead to an explosion, which causes potential for property damage, personal injury, or death.

Table 3 shows the supply current consumption of the system in different power modes.

Table 3. Supply Current Consumption

System State Supply Current (Typical)
Active mode (without eZ430 RF target) 2.1 mA
Active mode (with eZ430 RF target attached) 2.5 mA
Sleep mode (with eZ430 RF target attached) (1) 2 μA
(1) System is in low-power mode 3 (LPM3).