Renesas Synergy™ Platform
Target Board Kit S1JA (TB-S1JA)
R12UM0025EU0101 Rev.1.01
Page 10 of 31
Apr.21.20
5.2.1 Power Supply Options
TB-S1JA can be powered in several different ways as described in this section.
Figure 5. Power Supply Options
5.2.1.1 Option 1: Debug USB (Default)
The default power source is 5 V, supplied from an external USB host to the USB Debug connector labelled
DEBUG USB
on the top surface of the board. A low drop-out regulator (LDO) is used to convert the 5 V
signal to 3.3 V, which then is used to power the MCU and any connected devices.
Copper jumper E35 selects the source for the primary power input to the LDO regulator. By
default, this jumper is configured to provide power through the Debug USB connector.
Copper jumper E35 is closed for this configuration.
5.2.1.2 Option 2: Test Points TP3 and TP4
TB-S1JA can also be powered by installing a 5 V power source across TP3 (positive input) and TP4
(negative input). Copper jumper E35 must be opened to enable powering the board using these test points.
The on-board Low Dropout Regulator (see section 4.3, Major Components) has an
input voltage range of +3.3 V to +5.5 V, and a built-in current limit of 600 mA. Make
sure any external power source connected to TP3 and TP4 meets these requirements.
Figure 6. USB Debug Connector (J11), TP3, and TP4 on Target Board
5.2.1.3 Option 3: Test Points TP1 and TP2
TB-S1JA can also be powered by installing a 3.3 V source across TP1 (positive input) and TP2 (negative
input). Copper jumper E35 must be open to enable powering the board using these test points.
Figure 7. TP1, TP2, and LED1 on Target Board
These test points supply voltage directly to the S1JA MCU, the S124 J-Link MCU, and
other on-board circuitry. Use caution to ensure that any voltage connected in this
manner meets the power requirements for the active features. Power sources that are
outside of the published operating range for the active devices may cause degraded
performance or damage the board.