CH1788 Cermetek Microelectronics, CH1788 Datasheet - Page 6

• Manufacturer Part Number: CH1788
• Manufacturer: Cermetek Microelectronics

Specifications of CH1788

• Lead Free Status / RoHS Status: Supplier Unconfirmed

Cermetek Microelectronics, Inc.
2006 Cermetek Microelectronics, Inc.
NOTE:
PIN
15
18
19
20
21
22
10
11
12
13
14
8
9
NAME
1. All unused pins should be left unconnected when not required in a specific application,
2. See DC characteristics before attempting to drive an LED directly from the output of any pin.
GND
RING
RXD
DTR
TXD
RST
V
S1
S2
TIP
V-
V+
A2
CC
unless specifically directed otherwise.
TYPE
I/O
I/O
I/O
I/O
O
--
I
-
I
I
I
I
I
Data Terminal Ready. Active low. The response to this input is controlled by the
Rn command where n specifies the desired options and includes: returning the
modem to the command state, hanging up the modem, resetting the modem, and
placing the modem in zero power mode.
Optional Input. Active low. Used when implementing the Line In Use circuit.
Transmit Data. Serial transmit data input. Data starts with a high to low transition.
Mark or binary 1 condition is indicated by HIGH.
Reset. Active HIGH. This input must be asserted HIGH for at least 50 ms to reset
the modem.
commence. If a system reset is not available, let this pin float to enable the internal
reset circuitry.
Ring.
(PSTN) for normal operation. This line should be routed to the RJ-11C jack through
the recommended protection circuitry.
TIP.
(PSTN) for normal operation. This line should be routed to the RJ-11C jack through
the recommended protection circuitry.
Caller ID. Used to connect an external RC network to enable caller ID operation.
See the application circuit in the Schematic 4.
Caller ID. Used to connect an external RC network to enable caller ID operation.
See the application circuit in the Schematic 4.
Audio Port. Optional audio port input. Allows the internal DAA to be shared with
external voice, tone injection or call progress monitoring applications. See the
application circuits in the Schematic 2 and 3.
approved for data applications only. Inclusion of voice or other audio functions may
require additional certification by the FCC.
Audio Port. Optional audio port input. Allows the internal DAA to be shared with
external voice, tone injection or call progress monitoring applications. See the
application circuits in the Schematic 2 and 3.
approved for data applications only. Inclusion of voice or other audio functions may
require additional certification by the FCC.
Power Supply. 5 Volt DC +/- 5%. Supply noise should be less than 50 mV
available at for 3.3 volt DC operation, upon special request.
Ground. Circuit ground. Use recommended bypass capacitors between GND and
VCC.
Receive Data. Serial receive data output. Data starts with a high to low transition.
Received mark or binary 1 condition is indicated by HIGH.
Table 2.
Telephone connection requires an active public switched telephone line
Telephone connection requires an active public switched telephone line
CH1788 Pin Descriptions (Continued).
The RST pin must be returned LOW for normal operation to
Page 6
FUNCTION
CH1788 Surface Mount PLCC 2400bps Modem
Document No. 607-0018 Revision A6 (01/06)
Note that the CH1788 is FCC
Note that the CH1788 is FCC
pp
. Also