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USIM Deck
CD
If USIM card is absent, the CD connects to Ground.
If USIM card is present, the CD is open.
 
 
CD is a pin detecting of USIM in the USIM socket, in normal, there will be a detect pin 
in the USIM socket. 
W_DISABLE 
Pin 45 works as the W_DISABLE signal by normalization. The MC509 supports this 
function. MU609, ME209u-526, MU709 and ME909u are now planning this pin for 
W_DISABLE signal, while this pin is GPIO for MU509.   
This signal requires an external pull-up resistor, which should be pulled up to 
VCC_EXT1 (pin 32) or VCC_EXT2 (pin 31). The signal level differs between 30mm × 
30mm LGA modules. Therefore, the MC509 uses pin 31 to provide the pull-up power 
supply and the MU609/ME209u-526/ME909u/MU709/ME909s uses pin 32 to provide 
the pull-up power supply. The reference circuit diagram is shown in the following 
figure. A transistor is required to separate this signal from the host control signal. 
Table 2-6  Differences of W_DISABLE interface