Sim Card - Huawei U8666 Maintenance Manual

U8655
Maintenance Manual
Touchscreen Panel
Interface
VDD_2V8_TP
VREG_S3
TOUCH_INT
I2C1_SCL
I2C1_SDA
TOUCH_RST_N

9.4.15 SIM Card

The MSM7225A is not compatible with the SIM card interface. The PM8029's MPP pins are
used to convert voltage levels of the signals for communication between the MSM7225A and
the SIM card.
The voltage of VREG_L16_UIM1 can be set to 1.5–3.05 V. The USIM interface's operating
voltage is usually 1.8 V or 3.0 V. The following table describes the voltage level conversion
interface of the PM8029.
Signal for Interfacing
with the MSM
UIM1_MSM_CLK
UIM1_MSM_DATA
USIM card circuit
Issue 1.0 (2012-02-23)
Pin
VREG_L12_2P85 (PM8029)
VREG_S3 (PM8029)
GPIO_82 (MSM7225A)
GPIO_131 (MSM7225A)
GPIO_132 (MSM7225A)
GPIO_96 (MSM7225A)
Voltage Level
VREG_S3
NOTE
Considering that SIM card operations are frequent, transient-voltage-suppression (TVS) diodes are
added to the circuit to provide ESD and surge protection.
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
Description
Touchscreen panel analog power supply,
2.85 V
Touchscreen panel digital power supply and
I/O connector power supply, 1.8 V
Touchscreen panel interrupt signal
Touchscreen panel's I2C clock
Touchscreen panel's I2C data
Touchscreen panel reset signal
Signal for Interfacing
with the USIM Card
UIM1_RESET
UIM1_CLK
UIM1_DATA
9 Principles and Failure Analysis
Voltage Level
VREG_L16_UIM1
(configured by the
phone's firmware)
54