Nuvoton ARM ARM926EL-S, User Manual, Page: 8 / 25

NuMaker-emWin-RDK-N9H20
Mar. 26, 2021 Page 8 of 25 Rev 1.11
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NuMaker-emWin-RDK-N9H20 demo board power-on setting description
ND0 Note
L USB Recovery mode
H Normal mode
ND2 Note
L UART0 debug message output
H UART0 message disable
ND5 ND4 DRAM type Part No.
H H DDR N9H20K31N
L L SDRAM N9H20K11N
H L DDR2 N9H20K51N
L H LP-DDR Reserved
PGC5 GPC4 NAND PAGE Size
H H Auto by IBR
H L 8K
L H 4K
L L 2K
1.3.5 Power Desing Notes
NuMaker-emWin-RDK-N9H20 demo board power supply design have the below considerations

For system core power (1.8V) design, it is recommended to select DC-DC part and the output
capacity have 1A or above is better.

For IO power (3.3V), in NuMaker-emWin-RDK-N9H20 demo board also uses DC-DC part, the
concern is for LCD powered

Power up sequence, the I/O (3.3V) power should be equal or fast than the core (1.8V) power
and time gap between should control under within 500uS as the figure shown.

Power-down sequence, the Core (2.8V) power should be equal or fast than the I/O (3.3V) power.