User's Guide

UC864-E-AUTO / AWS-AUTO Hardware User Guide
1vv0300795 Rev.11 – 2010/11/18
Reproduction forbidden without Telit Communications S.p.A’s. written authorization - All Rights Reserved. Page 41 of 78
The levels for UC864-E-AUTO / AWS-AUTO UART are the CMOS levels:
Absolute Maximum Ratings
Absolute Maximum Ratings Absolute Maximum Ratings
Absolute Maximum Ratings -
--
- Not Functional
Not FunctionalNot Functional
Not Functional
Parameter
ParameterParameter
Parameter Min
MinMin
Min Max
MaxMax
Max
Input level on any
digital pin when on
-0.3V +3.0V
Input voltage on
analog pins when on
-0.3V +3.0 V
Operating Range
Operating Range Operating Range
Operating Range -
--
- Interface
Interface Interface
Interface L
LL
Levels
evelsevels
evels
Level
LevelLevel
Level Min
MinMin
Min Max
MaxMax
Max
Input high level 2.0V 2.9 V
Input low level -0.3V 0.6V
Output high level 2.15V 2.6V
Output low level 0V 0.45V
The signals of the UC864-E-AUTO / AWS-AUTO serial port are:
Internal pull-up or pull-down resistance is not a fixed value and it may differ from case by ca
se.
The resistance can be calculated from the DC characteristics considering a level of 2.6V DC.
In this case I_ILPU(input low leakage current with pull-up) is between -60 and -10uA.
Then the resistance can be calculated as V/I=2.6/60u ~ 2.6/10u = 43.3K ~ 260K.
In case of pull-down, it can be calculated in the same way.
Pin
PinPin
Pin Signal
SignalSignal
Signal I/O
I/OI/O
I/O Function
FunctionFunction
Function
Internal
InternalInternal
Internal
Pulls Up/Dn
Pulls Up/DnPulls Up/Dn
Pulls Up/Dn
Type
TypeType
Type
25
2525
25 C103/TXD I Serial data input (TXD) from DTE Pull-Down CMOS 2.6V
26
2626
26 C104/RXD O Serial data output to DTE Pull-Up CMOS 2.6V
27
2727
27 C107/DSR O Output for Data set ready signal (DSR) to DTE Pull-Down CMOS 2.6V
28
2828
28 C106/CTS O Output for Clear to send signal (CTS) to DTE Pull-Up CMOS 2.6V
29
2929
29 C108/DTR I
Input for Data terminal ready signal (DTR) from
DTE
Pull-Up CMOS 2.6V
30
3030
30 C125/RING O Output for Ring indicator signal (RI) to DTE Pull-Up CMOS 2.6V
31
3131
31 C105/RTS I
Input for Request to send signal (RTS) from
DTE
Pull-Down CMOS 2.6V
32
3232
32 C109/DCD O
Output for Data carrier detect signal (DCD) to
DTE
Pull-Up CMOS 2.6V