Hardware Manual

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TESSERA TECHNOLOGY INC.
3. Description of the power supply
Table Table 3-1 shows the various ways that power can be supplied to the board. There
is a normal power supply operation mode that supplies the board's internal power supply
and an EH (Energy Harvest) power supply operating mode that uses the Energy Harvest
Control Circuit (EHC) to supply the MCU VCC from the power generation element. The
EHC enables the MCU to be activated with a very small input current and provides
protection against secondary battery overcharging and over discharge. For more
information about EHC functionality, see Chapter 13 of the RE01B Group (1.5M Flash
Memory Products) User's Manual Hardware Edition (R01UH0903).
Table 3-1: How to Supply Power
power
Operating
mode
power
Supply source
explanation
Normal
power
supply
behavior
External power
supply (VCC-IN
terminal)
The power supply inside the board is supplied
directly from the stabilized power supply, etc.
USB
Generates internal power on the board using USB
bus power
Emulator E2
Power the inside of the board directly from the E2
emulator
Emulator J-Link
Generate the internal power supply of the board
using the power supplied by the J-Link emulator,
etc.
EH Power
behavior
Power Generation
Elements (VSC_VDD)
Supply MCU VCC from power generation elements
via EHC