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
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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 23 of 106
2.1.3.1 Interface implementation
Figure 5 shows a standard USB interfacing circuit for "off board" interfacing (connection directly
to a USB connector).
If the USB interface is directly wired to a Host interface, the additional ESD protection (U1 on
Figure 5) is not necessary, as the final product will not be a "hot swappable" item. The filter is
used to offer high impedance to higher frequency components of the USB signals. This helps
reduce any potential RF noise coming from these USB wires.
Figure 5: USB Additional ESD Protection Implementation
The digital signals USB_DP and USB_DN are sensitive to track design. Make sure these sig-
nals are routed with 90 Ohms differential resistance. If the host product is containing other USB
interfaces, then ensure that the rules used to design those are replicated here too. An overvolt-
age protection device U1 is recommended, such as ESD5V3U2U-03F.
USB_DP
USB_DN
GND
VUSB
GND
1
12
3
12
342
3
4
65
45
46
ELS31
ELS51
J1
USB-Type B
F1
U1