Specifications

L506 Hardware Design
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VOH
High-level output
voltage
2.75*VDD_E
XT
2.85
VDD_EXT
V
VOL
Low-level output
voltage
0
0
0.125*VDD_E
XT
V
SD card I/O load capacity for linear output displacement, concrete can be calculated according to the
following chart;
Figure 3-23 VOL/VOH IV curve
3.12.2 SD card interface design guideline
L506 VDD_EXT for external SD card interface ofpower supply, in the card slot position should add
the ESD protection circuit; If you need to support SD hot plug design need to add SD_DET signals.
Due to the default hot plug pin of L506 check for low level to identify the card insert status, so you
need to choose the detect PIN connected to the ground when SD card is inserted into the SD slot,
below is the reference circuit.
Figure 3-24SD card recommended circuit