User guide

UC864-E/G/WD/WDU Hardware User Guide
1vv0300766a Rev.4
- 03/02/09
Reproduction forbidden without Telit Communications S.p.A’s. written authorization - All Rights Reserved. Page 48 of 78
9.1. USB transceiver specifications
This is the on-chip USB transceiver specifications
Parameter Comments Min Typ Max Unit
USB_VBUS
Supply Voltage 4.5 5.0 5.25 V
Supply Current 11.7 15 mA
Termination Voltage An internal supply voltage, V
TRM
3.0 3.3 3.6 V
USB_ID (for future use only)
ID pin pull-up resistance 108 140 182 kΩ
A device detection
threshold
R
A_PLUG_ID
< 10Ω, or USB_ID pin
must be connected to GND
0.15
*V
TRM
V
B device detection
threshold
R
B_PLUG_ID
> 100kΩ, or USB_ID pin
is not connected
0.8 V
TRM
V
USB_D+, D-
Input sensitivity
(differential)
|D+ - D-| 0.2 V
Output voltage
Logic LOW
Logic HIGH
R
L
=1.5 kΩ to 3.6V
R
L
=15 kΩ to GND, I
O
=1mA 2.8
0.3
3.6
V
V
Input voltage
Logic LOW
Logic HIGH
R
L
=1.5 kΩ to 3.6V
R
L
=15 kΩ to GND, I
O
=1mA 3.0
0.3
3.6
V
V
Internal pull-up resistor V
TRM
to D+, V
TRM
to D- 1.425 1.5 1.575 kΩ
Internal pull-down resistor D+ to GND, D- to GND 14.3 15 24.8 kΩ