User's Manual

AC65/AC75 Hardware Interface Description
Confidential / Preliminary
s
AC65/AC75_hd_v00.372 Page 89 of 118 2006-08-03
Function Signal name IO Signal form and level Comment
V
OL
max = 0.3V at I = 0.1mA
V
OH
min = 2.3V at I = -0.1mA
V
OH
max = 3.05V
Synchroni-
zation
SYNC O
n Tx = n x 577µs impulse each 4.616ms,
with 180µs forward time.
There are two alternative
options for using the SYNC
pin:
a) Indicating increased
current consumption during
uplink transmission burst.
Note that the timing of the
signal is different during
handover.
b) Driving a status LED to
indicate different operating
modes of AC65/AC75. The
LED must be installed in the
host application.
To select a) or b) use the
AT^SSYNC command.
If unused keep pin open.
RTC backup VDDLP I/O R
I
 1k
V
O
max = 4.5V
V
BATT+
= 4.3V:
V
O
= 3.2V at I
O
= -500µA
V
BATT+
= 0V:
V
I
= 2.4V…4.5V at I
max
= 25µA
If unused keep pin open.
ASC0
Serial
interface
RXD0
TXD0
CTS0
RTS0
DTR0
DCD0
DSR0
RING0
O
I
O
I
I
O
O
O
V
OL
max = 0.2V at I = 2mA
V
OH
min = 2.55V at I = -0.5mA
V
OH
max = 3.05V
V
IL
max = 0.8V
V
IH
min = 2.15V
V
IH
max = VEXTmin + 0.3V = 3.05V
Internal pull-down at TXD0: R
I
=330kΩ
Internal pull-down at RTS0: R
I
=330kΩ
Serial interface for AT
commands or data stream.
If lines are unused keep pins
open.
ASC1
Serial
interface
RXD1
TXD1
CTS1
RTS1
O
I
O
I
V
OL
max = 0.2V at I = 2mA
V
OH
min = 2.55V at I = -0.5mA
V
OH
max = 3.05V
V
IL
max = 0.8V
V
IH
min = 2.15V
V
IH
max = VEXTmin + 0.3V = 3.05V
Internal pull-down at TXD1: R
I
=330kΩ
Internal pull-down at RTS1: R
I
=330kΩ
4-wire serial interface for AT
commands or data stream.
If lines are unused keep pins
open.