242
Agere Systems Inc.
T8302 Internet Protocol Telephone
Advanced RISC Machine (
ARM
)
Data Sheet
July 2001
19 Electrical Specifications
19.1 Absolute Maximum Ratings
Stresses in excess of the absolute maximum ratings can cause permanent damage; these are absolute stress rat-
ings only. Functional operation of the device is not implied at these or any other conditions in excess of those given
in the operational sections of this data sheet. Exposure to absolute maximum ratings for extended periods can
adversely affect device reliability.
19.2 Handling Precautions
Although protection circuitry has been designed into this device, proper precautions should be taken to avoid expo-
sure to electrostatic discharge (ESD) during handling and mounting.
Agere
employs a human-body model (HBM)
and a charged-device model (CDM) for ESD-susceptibility testing and protection design evaluation. ESD voltage
thresholds are dependent on the circuit parameters used to define the model.
The following table shows voltage ratings for CDM and HBM.
Note:
In V5 of the T8302, silicon changes were implemented to improve ESD margins to within the limits specified
below.
19.3 Crystal Specifications
19.3.1 System Clock Crystal
The T8302 requires an 11.52 MHz clock source (derived from an oscillator or a crystal) for the system clock source.
If a crystal is used it must be connected between XTAL0 and XTAL1. The crystal specifications are shown below.
Table 210. Absolute Maximum Ratings
Parameter
Symbol
V
DD
—
—
—
—
Min
—
V
SS
Max
3.5
V
DD
5.5
70
125
Unit
V
V
V
°
C
°
C
Supply Voltage
XRTC0, XRTC1, XTAL0, XTAL1, XLO, XHI
Voltage Applied to I/O Pins
Operating Temperature
Storage Temperature
V
DD
–0.3
0
–40
Model
CDM
HBM
Threshold Voltage Rating
250 V to < 500 V
1000 V to < 2000 V
Table 211. System Clock (XTAL0, XTAL1) Specifications
Parameter
Value
11.52 MHz
Frequency.
Oscillation Mode.
Effective Series Resistance.
Load Capacitance.
Shunt Capacitance.
Frequency Tolerance and Stability.
Fundamental, parallel resonance
A discussion of crystal selection for the T8302 may be found
in the application note
Crystal Selection for the T8301/T8302
Chip Set
.
±
50 ppm