CH1840D ET Cermetek Microelectronics, CH1840D ET Datasheet - Page 4

• Manufacturer Part Number: CH1840D ET
• Manufacturer: Cermetek Microelectronics

Specifications of CH1840D ET

• Operating Temperature Classification: Industrial
• Pin Count: 12
• Lead Free Status / RoHS Status: Supplier Unconfirmed

Cermetek Microelectronics, Inc.
©2009 Cermetek Microelectronics, Inc.
Pin
10
11
12
1
2
3
4
5
6
7
8
9
XMIT(+)
OFFHK
XMIT(-)
Name
RING
GND
PSQ
RCV
VCC
N/C
D/V
TIP
RI
I/O
I/O
I/O
O
O
O
-
I
I
I
I
I
I
TIP. Direct connection to the telephone line through a standard jack.
RING. Direct connection to the telephone line through a standard jack.
Not Used. Please leave unconnected
OFF HOOK, Input. When set LOW, the CH1840 is placed On-Hook. When set
HIGH, the CH1840 is placed Off-Hook to answer or place a call. This input can also
be used for pulse dialing.
RING INDICATION, Output. RI is driven LOW during the typically 2 second ring
period and HIGH during the typically 4 seconds between rings. RI is otherwise HIGH.
NOTE: RI pulses square wave along with ring signal frequency. The square wave
can be suppressed to produce an envelope of the AC ring with the application circuit
shown in Figure 2.
DATA/VOICE SELECT, Input. When driven LOW or left unconnected, Data Mode is
selected and the Billing Delay and Power Squelch are enabled. When driven HIGH,
Voice Mode is selected and the Billing Delay and Power Squelch are disabled.
POWER SQUELCH, Output. PSQ indicates the status of the signal limiting squelch
circuit. When PSQ is HIGH, the transmit path is squelched. PSQ is also active when
On-Hook and in Data Mode.
RECEIVE, Output. RCV is the audio signal received from the phone line. This output
is symmetrical with respect to +2.5V. AC coupling is recommended for most designs.
Input must be used with pin 11 in differential mode only. When not used, please
leave unconnected.
+5V Power Supply, Input.
TRANSMIT, Input. Analog signal input. Audio data and voice signals presented here
will be monitored for excessive power, filtered through a bandpass, and applied to the
phone line unless squelched. One input pin of two when used in differential mode
with pin 9.
SIGNAL AND POWER COMMON GROUND, Input.
Table 1.Pin descriptions
Page 4
Function
CH1840 Family of Low Profile DAA Modules
Document No. 607-0011 Revision C (09/09)