User's Manual

EHS5-E/EHS5-US Hardware Interface Overview
2.1 Application Interface
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EHS5_HIO_v01.000 Page 14 of 35 2012-11-14
Confidential / Preliminary
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The figure below shows a circuit to connect an external SIM card holder.
Figure 5: External UICC/SIM/USIM card holder circuit
The total cable length between the SMT application interface pads on EHS5-E/EHS5-US and
the pads of the external SIM card holder must not exceed 100mm in order to meet the specifi-
cations of 3GPP TS 51.010-1 and to satisfy the requirements of EMC compliance.
To avoid possible cross-talk from the CCCLK signal to the CCIO signal be careful that both
lines are not placed closely next to each other. A useful approach is using a GND line to shield
the CCIO line from the CCCLK line.
2.1.5 Digital Audio Interface
EHS5-E/EHS5-US’s digital audio interface (DAI) can be used to connect audio devices capable
of pulse code modulation (PCM).
2.1.6 GPIO Interface
EHS5-E/EHS5-US offers a GPIO interface with 4 GPIO lines
1
. The GPIO lines are shared with
other interfaces: Status LED (see Section 2.1.9) or the PWM functionality (see Section 2.1.8).
The following table shows the configuration variants of the GPIO pads. All variants are mutually
exclusive, i.e. a pad configured as GPIO is locked for alternative use.
1. The GPIO functionality will be available as of Release 2.
SIM
CCVCC
CCRST
CCIO
CCCLK
220nF
1nF
CCIN
V180