Uim Card; How The Uim Card Works; Uim Card Troubleshooting - Nokia 3155i Troubleshooting Manual

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UIM Card

How the UIM Card Works

The Nokia 3155/3155i/3152 supports two types of UIM cards that work at 1.8V and 3.0V.
When the mobile terminal is switched on with a UIM card, the D2800 sends a 1.8V signal
to the UIM card and waits for the UIM card's response and identification. After a wait
period, if there is no answer from the UIM card, the mobile terminal will send another
signal at 1.8V. In this case UEMEK acts as a level shifter and raises the signal to 3.0V. If
there is still no response, the mobile terminal will not allow access. If there is a response,
then the mobile terminal powers up.

UIM Card Troubleshooting

When troubleshooting UIM cards, make these common checks (see
Figure 31):
• Check Vsim 1.8V or 3.0V. Vsim comes from UEMEK and goes through the SIM ESD
protection chip. Check for bad or damaged solder joints. Replace chips if
necessary.
ISSUE 1 07/2005
Figure 29: UIM Card Block Diagram
©2005 Nokia Corporation
3155/3155i (RM-41), 3152 (RM-61)
Baseband Description and Troubleshooting
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Figure 30 and
Page 31