User's Manual
Table Of Contents
- Contents
- Tables
- Figures
- 1 Introduction
- 2 Interface Characteristics
- 2.1 Application Interface
- 2.1.1 Pad Assignment
- 2.1.2 Signal Properties
- 2.1.3 USB Interface
- 2.1.4 Serial Interface ASC0
- 2.1.5 Serial Interface ASC1
- 2.1.6 UICC/SIM/USIM Interface
- 2.1.7 Digital Audio Interface
- 2.1.8 Pulse Code Modulation Interface (PCM)
- 2.1.9 Inter IC Sound Interface (I2S)
- 2.1.10 GPIO Interface
- 2.1.11 I2C Interface
- 2.1.12 SPI Interface
- 2.1.13 Pulse Counter
- 2.1.14 HSIC Interface (ELS51-VA Only)
- 2.1.15 SDIO Interface (ELS51-VA Only)
- 2.1.16 Control Signals
- 2.2 RF Antenna Interface
- 2.3 Sample Application
- 2.1 Application Interface
- 3 Operating Characteristics
- 3.1 Operating Modes
- 3.2 Power Up/Power Down Scenarios
- 3.3 Power Saving
- 3.4 Power Supply
- 3.5 Operating Temperatures
- 3.6 Electrostatic Discharge
- 3.7 Blocking against RF on Interface Lines
- 3.8 Reliability Characteristics
- 4 Mechanical Dimensions, Mounting and Packaging
- 5 Regulatory and Type Approval Information
- 6 Document Information
- 7 Appendix
Cinterion
®
ELS31-VA/ELS51-VA Hardware Interface Description
2.1 Application Interface
56
ELS31-VA_ELS51-VA_HID_v01.000 2017-01-04
Confidential / Preliminary
Page 36 of 106
2.1.11 I
2
C Interface
I
2
C is a serial, 8-bit oriented data transfer bus for bit rates up to 100kbps. It consists of two lines,
the serial data line I2CDAT and the serial clock line I2CCLK. The module acts as a single mas-
ter device, e.g. the clock I2CCLK is driven by the module. I2CDAT is a bi-directional line. Each
device connected to the bus is software addressable by a unique 7-bit address, and simple
master/slave relationships exist at all times. The module operates as master-transmitter or as
master-receiver. The customer application transmits or receives data only on request of the
module.
To configure and activate the I2C bus use the AT^SSPI command. Detailed information on the
AT^SSPI command as well explanations on the protocol and syntax required for data transmis-
sion can be found in [1].
The I
2
C interface can be powered via the V180 line of ELS31-VA/ELS51-VA. If connected to
the V180 line, the I
2
C interface will properly shut down when the module enters the Power
Down mode.
In the application I2CDAT and I2CCLK lines need to be connected to a positive supply voltage
via a pull-up resistor. For electrical characteristics please refer to Table 2.
Figure 14: I
2
C interface connected to V180
Note: Good care should be taken when creating the PCB layout of the host application: The
traces of I2CCLK and I2CDAT should be equal in length and as short as possible.
I2CCLK
I2CDAT
GND
I2CCLK
I2CDAT
GND
Module Application
V180
R pull up
R pull up
R pull up
R pull up