Gemalto M2M GmbH ALS1-US Manual Do Utilizador

®

3.3 USB Interface



ALS1-US_HIO_v01.000

2013-08-14

Confidential / Preliminary

Page 20 of 34

ALS1-US supports a USB 2.0 High Speed (480Mbit/s) device interface that is Full Speed 

(12Mbit/s) compliant. The USB interface is primarily intended for use as command and data 

interface and for downloading firmware. 

The USB host is responsible for supplying the VUSB_IN line. This line is for voltage detection 

only. The USB part (driver and transceiver) is supplied by means of BATT+. This is because 

ALS1-US is designed as a self-powered device compliant with the “Universal Serial Bus Spec-

ification Revision 2.0”

1

.

USB circuit

To properly connect the module's USB interface to the host a USB 2.0 compatible connector is 

required. Furthermore, the USB modem driver distributed with ALS1-US needs to be installed.

1.

The specification is ready for download on 

DP

DN

VREG (3V075)

BATT+

USB_DP

3)

lin. reg.

GND

Detection only

VUSB_IN

2)

1)

 All  serial (including R

S

) and pull-up resistors for data lines are implemented.

USB_DN

3)

3)

 If the USB interface is operated in High Speed mode  (480MHz), it is recommended to take 

special care routing the data lines USB _DP and USB_DN. Application layout should in this 

case implement a differential impedance of 90Ohm for proper signal integrity.

R

S

R

S

VBUS

1µF

2)

 Since VUSB_IN is used for detection only it is recommended not to add any further 

blocking capacitors on the VUSB_IN line.

SMT