ETC CH2000ET

Cermetek
microelectronics
CH2000 Low Profile Full Function
2400 bps Modem
INTRODUCTION
At 0.34 inches (nominal), Cermetek’s CH2000 is the lowest
profile full function FCC Part 68 approved modem
commercially available. It has been designed to be used in
applications where an extremely low profile is required. The
CH2000 fully supports V.22bis and associated standards
and is controlled through the AT command set.
FEATURES
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Supports Standards CCITT V.22bis, V.22,
Bell 212, and Bell 103
FCC Part 68 approved and DOT CSA CS-03 Part I
approvable
AT Command structure available
1000 VAC isolation barrier
Single 5 volt operation
Low power sleep mode
Automatic adaptive and fixed compromise
equalization
Test modes and diagnostics
Size: 2.0” x 1.12” x 0.34” (nominal)
NVRAM allows storage of custom configurations
and telephone numbers
Commercial Operating temperature 0o to 70oC
Extended temperature -40oC to 85oC order
CH2000ET
DESCRIPTION OF FUNCTIONAL BLOCKS
AND DISCUSSION OF BASIC OPERATIONS
Figure 1 contains a functional block diagram of the CH2000.
The CH2000 is a highly integrated, full function modem,
comprised of a modulator/demodulator, controller, NVRAM
(Non-Volatile Ram) and an FCC Part 68 approved telephone
interface (Data Access Arrangement -DAA).
Modulation/Demodulation and Modem
Controller.
Figure 1. Functional Block Diagram of CH2000.
equivalent. This label should be prominently displayed on any
system containing the CH2000. With the exception of the U.S.,
most countries (including Canada) require submission of the
final product or system containing the CH2000 for regulatory
agency approval. This is typically done by submitting the design
to a test house or consultant for evaluation against the applicable
regulatory standards. Call Cermetek for a consultant list.
Non-Volatile RAM (NVRAM).
The NVRAM present on the CH2000 is sufficient to store up to two
user customized modem configurations. The AT&Wn command
will store the active modem configuration in the selected NVRAM
locations by specifying an n of 0 or 1. The AT&Yn command selects
the modem configurations to be automatically recalled and made
active upon a reset or power up. The ATZn command immediately
recalls and activates a stored configuration. Refer to Tables 4 and
5 for storeable S-Registers and available commands.
SUPPORTED FEATURES
These functions are provided by a monolithic modem integrated circuit. This IC has built-in facilities accomodating
integrated “AT” command control and containing the necessary resident interfaces for general communication and
routing to the DAA.
“AT” Command Set.
Telephone Line Interface or DAA.
Serial Host Interface.
The CH2000 is designed to comply with North American telephone
standards as set by FCC Part 68 (USA) and DOT CSA CS-03
Part I (Canada). Among the more critical parameters, the CH2000’s
telephone line interface provides 1000VAC and 1500 volt peak
surge isolation. Consequently, the CH2000 satisfies U.S. and
Canadian requirements and will meet other international requirements that specify this high level of isolation. The CH2000 is FCC
Part 68 preapproved and is shipped from the factory with an FCC
Part 68 approval label indicating the registration number and ringer
1999 Cermetek Microelectronics, Inc.
The CH2000 supports a 40-character command line. The command line starts with AT and may contain standard or enhanced
commands.
See Cermetek’s command summary at
(www.cermetek.com), for a detailed discussion of AT Commands.
The CH2000 utilizes a V.24 (EIA-232-D) compatible interface. Refer
to the pin descriptions in Table 2.
Speaker Interface.
The SPK output reflects the receiver analog input and provides a
signal that can be used to monitor call progress. The SPK signal
can drive a 300 Ω load directly. Typically, the SPK signal is input
into an audio power amplifier and the amplifier, inturn, drives a
speaker coil.
Document No.607-0002 Rev. D (8/99)
1
The speaker is activated with the ATMn command. The speaker
volume is adjusted using the ATLn command, where n is 0, 1, 2,
or 3. Increasing numbers correspond to higher volume. Figure 5
illustrates one technique of driving an external 8Ω speaker.
Phone Control.
Cermetek’s CH2000 contains a pin called Voice/Data (V/D). The
V/D pin toggles high when the modem goes off hook. This pin
can be used to activate a relay which can switch a telephone on
or off the Tip and Ring incoming PSTN lines. This feature allows
any telephone associated with the CH2000 to be disconnected
when a data call is in progress, thereby preventing the data from
being disturbed by an inadvertent telephone pick-up. See Figure
2.
RING
TIP
TIP
RING
RJ-11
Jack
OPTIONAL
PHONE
RJ-11
Jack
TELEPHONE
LINE
Table 1. Connection Rates.
An sw erin g Mo d em In itial
Train ed R ate
C o n n ectio n R ate R esu ltin g Wh en
C allin g Mo d em In itial Train ed R ate is:
300
1200
2400
300
300
1200
1200
1200
300
1200
1200
2400
300
1200
2400
Speed and Parity Selection.
Prior to call initiation, the host controller trains the modem to the
host speed (2400, 1200, or 300 bps) and parity (odd, even, mark,
space, or none) via a host-initiated training sequence. This training also sets the speed of the data for originate calls. The CH2000
will automatically adjust to the originators speed when answering
calls.
The CH2000 matches the host’s parity when it returns status messages to the host. During a data connection, however, the modem
passes parity through without interpretation or alteration.
Ring Indicator (RI).
Figure 2. Voice/Data Port Control.
Sleep Mode.
To minimize power consumption, the CH2000 includes a power
down feature called Sleep Mode. When activated, the CH2000
will automatically enter Sleep Mode after 0 to 254 seconds of inactivity. The inactivity delay is selected using the ATS24 command.
The CH2000 is delivered from the factory with a 5 second inactivity
delay enabled (i.e., ATS24=5). The CH2000 returns to normal
operation when a ring signal is received or upon an input low
signal on the TXD pin. ATS24 = 255 disables the Sleep Mode and
is the default if no value is set in register S24.
A SLEEP output signal is available to control power to external
devices. In Figure 5, a FET controlled by the SLEEP signal turns
off the external speaker amplifier when the CH2000 enters Sleep
Mode. In Sleep Mode, power is reduced to approximately 50% of
normal operating power.
Transmission Speed.
In normal operation, the originating modem initiates the call and
attempts to connect to the answering modem at a speed established by the originating modems controller prior to call initiation.
This is referred to as the Initial Trained Rate. Upon receiving the
call, the answering modem will attempt to connect to the originating modem at its Initial Trained Rate.
If these two rates are identical, the connection is made. If the
speeds differ, the answering modem must adjust its rate or terminate the call. Table 1 indicates the connection rate that will result
when the calling modem’s Inital Trained Rate and the answering
modem’s Initial Trained Rate are different.
Note that a 2400 baud connection rate will only result if both modems are initially set at 2400 baud.
1999 Cermetek Microelectronics, Inc.
The RI pin toggles low when the CH2000 detects an incoming call.
Although not TTL compliant, the RI pin can, nonetheless, be utilized to activate external circuitry including the external RST pin.
When using the RI pin, it is recommended that a Schmitt Trigger or
the Isolated Envelope Detect Circuit in Figure 4 be placed between
the RI pin and the external load.
Power Supply.
The CH2000 modem module is a complex set of sub-systems.
During the course of normal operation the CH2000 decodes analog signals from the telephone line that are in the millivolt range.
Steps must be taken by the user to guarantee that power supply
noise on all supply lines, including ground, does not exceed 50
mV peak to peak. Any frequency between 20 kHz and 150 kHz must
be less than 500 µV peak. If necessary, use dedicated power and
ground planes. Failure to provide such operating conditions could
cause the CH2000 to malfunction or to function erratically.
The CH2000 requires a single +5V ±5% supply. It is recommended
that by-pass capacitors be placed on the power supply as close to
the modem’s supply input as practical. It is recommended that a
10 µF Electrolytic capacitor in parallel with a 0.01µF ceramic capacitor be used.
WARNING: The CH2000 has been FCC Part 68 approved as a
data modem only. Utilization of the Voice/Tone Port requires further
registration. FCC will require that the system, including the CH2000
and the handset or DTMF transceiver, adhere to Part 68 rules.
MODEM CONTROL
The CH2000 modem may be controlled by sending serial ASCII
command sequences. The commands are sent to the modem
serially on the TXD pin. After execution of a received command, the
modem returns a serial status message that can be read on pin
RXD. This message indicates command completion status. Refer to Table 3 for a complete list of result codes.
Document No. 607-0002 Rev. D (8/99)
2
INITIALIZING THE MODEM
Before commands may be sent to the CH2000, the modem must
be initialized. This consists of two events:
1) Power-up reset . This is accomplished by applying a hardware
reset pulse to pin RST.
2) Initial modem training. The modem must be trained to the
host’s speed (2400, 1200, 300bps) and parity (odd, even, mark,
space or none).
ENABLE RXA
MECHANICAL RELAY ONLY.
A ZERO IMPEDANCE SWITCH MAY REPLACE
THE RELAY AND TRANSISTOR CIRCUIT.
+5V
4.7K
2N2222
1N914
+15V
1 RING
2 TIP
20K
CH2000
3
AXT
4
+
20K
A
1
B
499
2
TL064
2.2uF
nonpolar
0.1uF
0.1uF
82K
0.1uF
20K
These activities are briefly described below.
63.4K
7 RXA
8 DTR
9 NC
10 V/D
11 RST
12 RI
13 NC
14 DSR
VOICE OR DTMF
SIGNAL
16 TXD
17 NC
Power-up Reset.
R1
After applying power to the CH2000, the CH2000 generates an
internal reset pulse. The user can also reset the modem externally by applying a high-going reset pulse to the RST pin for at
least 10ms after the +5V power supply has stabilized. Delay sending commands to CH2000 for 200ms after Power-up reset has
been initiated to allow the CH2000 to properly reset.
15 NC
20K
54K
NC 34
GND 33
VCC 32
RXD
NC
NC
31
30
29
NC
SPK
NC
NC
NC
NC
28
27
26
25
24
23
HS 22
18 NC
DCD 21
19 SLEEP
GND
20
6
-
7
5
AXR
0.1uF
11
+
28K
R2
TL064
0.1uF
Training the Modem.
Each modem must be trained to match its host’s speed and parity
so that it is able to recognize serial asynchronous commands
sent to it by the host UART. The host must retrain the modem each
time a reset signal is applied on RST or after a RESET serial
command has been issued.
ADJUST R2 FOR THE DESIRED LEVEL OF AXT VOICE TO BE ECHOED TO AXR.
DECREASE RECEIVE GAIN SIGNAL AXR BY DECREASING VALUE OF R1.
Figure 3. Voice/Tone Injection.
RING
ANALOG VOICE
INJECTED SIGNALS
RXA
TXA
RJ-11
JACK
TIP
TELEPHONE
LINE
VOICE/DATA
SPK
CH2000
V.24
EIA-232-D
INTERFACE
OR
USART
OPTIONAL
PHONE
CONTROL
RELAY
SPEAKER
CONTROL
RXD
HS
DCD
DSR
RI
CTS
TXD
DTR
EXTERNAL RESET
RST
+5V
GND
EARTH GND*
Figure 4. CH2000 Application Diagram of Test Circuit.
1999 Cermetek Microelectronics, Inc.
Document No.607-0002 Rev. D (8/99)
3
Table 2. CH2000 Pin Descriptions (Continued).
P IN
N AME
I/O
F U N C T ION
20
GND
-
G R O U N D . N o t e : N o i s e s ho ul d b e l e s s t ha n 5 0 m V p e a k t o p e a k .
21
____
DCD
O
D AT A C A R R I E R D E T E C T o ut p ut . L O W i nd i c a t e s a d a t a c a r r i e r fr o m a r e m o t e
m o d e m i s d e t e c t e d . D C D fo l l o w s c a r r i e r i s t he d e fa ul t .
22
__
HS
O
S P E E D I N D I C AT I O N . H i g h s p e e d s e l e c t o ut p ut . A L O W o n t hi s p i n i nd i c a t e s t he
m o d e m i s o p e r a t i ng a t 2 4 0 0 b p s .
23
NC
-
N o c o nne c t i o n.
24
NC
-
N o c o nne c t i o n.
25
NC
-
N o c o nne c t i o n.
26
NC
-
N o c o nne c t i o n.
27
SPK
O
S P E A K E R . A ud i o O ut p ut . S e e F i g ur e 5 .
28
NC
-
N o c o nne c t i o n.
29
NC
-
N o c o nne c t i o n.
30
NC
-
N o c o nne c t i o n.
31
____
RX D
O
R E C E I V E D AT A . S e r i a l r e c e i v e d a t a o ut p ut . R e c e i v e d m a r k i ng o r a b i na r y 1
c o n d i t i o n i s i n d i c a t e d b y a H IG H .
32
VCC
-
P O W E R S U P P L Y . 5 V o l t s + 5 % i s r e q ui r e d . N o t e : N o i s e s ho ul d b e l e s s t ha n
5 0 mV p e a k to p e a k .
33
GND
-
G R O U N D . N o t e : N o i s e s ho ul d b e l e s s t ha n 5 0 m V p e a k t o p e a k .
34
NC
-
N o c o nne c t i o n.
Notes: (1)
(2)
(3)
(4)
(5)
If VCC has a slow power up ramp time, the internal reset may be ineffective.
I means input only.
O means output only.
I/O means both input and output possible.
NC means no connection.
1999 Cermetek Microelectronics, Inc.
Document No. 607-0002 Rev. D (8/99)
4
Modem Training Command Sequence.
The CH2000 is trained by sending it the following sequence:
Enter: AT[CR]
Where: A and T may be either upper or lower case but must be the
same case.
[CR] repesents carriage return
The “AT” sequence is referred to as an attention sequence. The
CH2000 will respond with one of the following status messages,
depending on whether it is optioned for abbreviated or English
status messages.
Result: 0[CR]
(Abbreviated form)
Result: [CR][LF]OK[CR][LF] (English form)
Where: [CR] represents carriage return (ASCII 13 or HEX 0D).
[LF] represents line feed (ASCII 10 or HEX 0A).
The modem is now in idle mode and is ready to accept commands.
An alternate attention sequence “A/” may be sent which behaves
much like the AT sequence except that it causes the previously
entered command specified with an AT prefix to be executed.
When given, it must be in upper case ASCII. No carriage return is
needed.
THE COMMAND FORMAT
Typical commands consist of three elements: the attention sequence, the commands themselves, and a terminating carriage
return.
AT [commands] [CR].
Where: AT represents attention sequence.
[commands] represents command strings.
[CR] represents carriage return (ASCII 13 or HEX 0D).
When entering commands to the modem, the backspace character-control-H (ASCII 8 or HEX 08) can be used to edit mistakes.
“AT” and “A/” may not be edited however. Multiple commands may
be placed in the command line. A command line may be as long
as 40 characters, excluding the letters AT. By way of example, the
command below instructs the CH2000 to configure itself to not
echo characters when in command mode (E0) and then put itself
in answer mode (A).
Enter: ATE0A[CR]
AT Command Set.
The available command set is divided into four types of commands: dial modifiers, basic commands, ampersand and percent commands. Refer to the complete list in Tables 4A, 4B and
4C, 4D respectively.
AT Command Data Rate.
With the serial interface, the rate is speed sensed for parity and
format.
THE STATUS MESSAGES
The CH2000 responds with a status message after each command is executed. This status message may either be a single
digit followed by a carriage return or a carriage return and line feed
with a message in English, followed by a carriage return and line
feed.
by the user.
X0 - Result Codes 0, 1, 2, 3, 4 allowed
X1 - Result Codes 0, 1, 2, 3, 4, 5, 10 allowed
X2 - Result Codes 0, 1, 2, 3, 4, 5, 6, 10 allowed
X3 - Result Codes 0, 1, 2, 3, 4, 5, 7, 10 allowed
X4 - Result Codes 0, 1, 2, 3, 4, 5, 6, 7, 10 allowed
The CH2000 is factory set to X4, which allows all result codes.
MODEM STATES
The CH2000 can be in either command mode or data mode. When
the modem is idle, it is in command mode by default. When data
transmission is in progress, the CH2000 is in the data mode state
and will not recognize commands. To force the CH2000 to recognize commands, the host must send an “escape sequence” to the
CH2000 forcing it out of data mode and into command mode.
The escape sequence consists of a “guard time” (a period where
no characters are sent to the modem), followed by 3 escape
characters, followed by another guard time. At power up, the guard
time is set to 1 second minimum, and the escape character is set
as “+.” These two parameters can be modified via registers S12
and S2, respectively.
The CH2000 will stay off-hook with its carrier on after the escape
sequence is received and it returns an OK status message when
it is ready to accept commands. The CH2000 can be put into data
mode by issuing the command ATO [CR].
Table 3. Summary of Result Codes and Their meanings.
Re sult
Codes
Sta tus
Me ssa g e s
Me a ni ng
0
OK
C o mma nd e xe cute d
1
C ONNE C T
C a rri e r d e te cte d a t 300 b p s
2
RING
Ri ng d e te cte d
3
NO C A RRIE R
D i d no t d e te ct ca rri e r
4
E RROR
E ntry e rro r
5
C ONNE C T 1200
C a rri e r d e te cte d a t 1200 b p s
6
NO D IA L TONE
Off-ho o k, b ut no re sp o nse a fte r
5 se co nd s
7
B US Y
B usy si g na l d e te cte d
10
C ONNE C T 2400
C a rri e r d e te cte d a t 2400 b p s
Table 4A. Dial Modifiers and Functions.
Dial Modifers
Function
P
R
T
W
;
@
!
,
0-9
A,B,C,D
Pulse Dial
Originate Call in Answer Mode
Touch Tone Dial
Wait for Dial Tone
Return to Idle State
Wait for Quiet Answer Command
Flash hook
Pause
Dial Digits/Characters
The basic status code subsets are enabled with the Xn command. Where n=0,1,2,3,4 establishes the result codes allowed
1999 Cermetek Microelectronics, Inc.
Document No.607-0002 Rev. D (8/99)
5
Table 4B. CH2000 “AT” Command Set Summary.
CH2000 “AT” Set Summary
Basic Commands
AT
A
A/
*Bn
D
*E
Hn
*Ln
*Mn
On
P
*Qn
Sn
Sn=
Sn?
*Vn
*Xn
+++
,
?
*Yn
Fn
Z
Function
Attention Code
Answer command
Repeat Last Command
Communications Standard Option
Dial Command
Off-Line Character Echo Option
Switch Hook Control Option
Speaker Volume Option
Speaker Control Option
On-Line Command
Pulse Dial
Result Code Display Option
Select an S Register
Write to an S Register
Read an S Register
Result Code Form Option
Result Code Set/Call Progress Option
Escape Code Sequence
Pause
Returns Last Addressed S Register
Long Space Disconnect Option
On Line Echo character Option
Reset
Table 4C. Ampersand Commands.
Ampersand
Commands
Function
*&Dn
&F
*&Gn
*&Pn
*&Sn
&Tn
&V
*&Wn
*Yn
*&Zn
*&Cn
Data Terminal Ready Option
Load Factory Defaults
Guard Tone Option
Make to Break Ratio Selection
Data Set Ready Option
Test Command Option
View Active Configuration
Store active profile
Recall active profile
Store telephone numbers
Data Carrier Detect Option
*= Commands that can be stored in NVRAM.
Table 4D. Percent Commands.
Percent
Commands
Function
%Dn
DTMF Attenuation
%J
Load Secondary Factory Defaults
NOTE:
A detailed definition of all commands and registers
is available from Cermetek Microelectronics, Inc.
Refer to Cermetek document “AT Commands and
S-Registers Reference Guide.”
1999 Cermetek Microelectronics, Inc.
Table 5. CH2000 Register Summary.
Register
CH2000 Register Summary
Function
S0*
Ring to Answer On
S1
Ring Count
S2
Escape Code Character
S3
Carriage Return Character
S4
Line Feed Character
S5
Back Space Character
S6
Wait For Dial Tone
S7
Wait Time for Data Carrier
S8
Pause Time for Comma
S9
Carrier Detect Response Time
S10
Lost Carrier to Hang-up Delay
S11
DTMF Dialing Speed
S12
Escape Code Guard Time
S14*
Bit Mapped Options Register
S16
Modem Test Options
S18*
Test Timer
S21*
Bit Mapped Options Register
S22*
Bit Mapped Options Register
S23*
Bit Mapped Options Register
S24
Sleep Mode Inactivity Time
S25*
Delay to DTR
S27*
Bit Mapped Options Register
S28*
Bit Mapped Options Register
*=S-Registers stored in NVRAM upon receipt of &W command
AT COMMAND APPLICATIONS
Dialing A Phone Number.
The Dial command takes the form Dn, where n is a string of characters. In the simplest form, n will be only the digits of the phone
number to be dialed.
Example: Dial number.
Enter: AT D1234567
In response to this command, the CH2000 dials the telephone
number “123-4567” and then waits for a carrier from the distant
modem. If no carrier is detected within a given time (the default
time is 30 seconds), the CH2000 automatically releases the line
and sends a NO CARRIER result code. If a carrier is detected, the
CH2000 gives a CONNECT result code and goes on-line, permitting communication with the distant modem.
The Dial Command may also be issued without a telephone number. ATD causes the modem to pick up the telephone line without
dialing a number.
Pause During Dialing.
When placing a call from an office with a telephone connected to a
PBX, it may be necessary to dial an access code (usually the digit
9) to get an outside line. Inserting a comma in the telephone
number instructs the modem to pause for a specific length of time.
The factory set default pause time is 2 seconds.
Example: Dial 9, pause, dial number.
Enter: AT DT9, 1234567
Multiple commas may be used to generate integer multiples of the
specified delay time.
Document No. 607-0002 Rev. D (8/99)
6
Originate a Call in Answer Mode.
The D command forces the modem into originate mode. To call
an originate-only modem, dial the number and set the modem to
answer mode via the R (reverse originate). This is done by
entering the R command at the end of the telephone number.
+5V
3
2
G
VN0300L
S
SLEEP
Redial Last Number.
D
1
Use A/, the repeat command, to redial the last telephone number
dialed when a busy signal is received.
10 uf
+
16V
6
7
+
LM386
2 _
220 uf
3
SPK
Return to Command State.
0.1 uf
0.01 uf
The modem can be forced to reenter the command state after
dialing (without hanging up) by ending the dial command with a
semicolon. This is useful when using the modem as an auto
dialer.
Example: Touch-tone dial 9, pause, dial number, return for
command.
Enter: AT DT9, 1234567;
Result: OK
4
16V
5
+
1
8
+
10 uf
8 Ohm
SPEAKER
1K
Figure 5. Speaker Control Circuit--optional to allow for call
progress monitoring.
Automatic Answering.
The S0 register controls the number of rings that must occur
before the modem answers a call. The register may range in
value from 0-255.
S0 = 0
S0 = 1
S0 = 2
S0 = 3
DO NOT ANSWER TELEPHONE
ANSWER ON RING 1
ANSWER ON RING 2
ANSWER ON RING 3
S0 = 255
ANSWER ON RING 255
When S0 is set to 0, the modem will not auto-answer.
CONNECTING TO THE HOST UART
Since a modem communicates data serially and most host products handle data in a parallel format, a UART is needed to make
parallel-to-serial and serial-to-parallel translations.
PHONE LINE CONNECTION GUIDELINES
1)
2)
3)
4)
5)
The Serial Interface Lines.
The CH2000 supports a full EIA-232D/V.24 serial interface. Signal
levels are TTL rather than EIA-232D level compatible, which allows you to directly connect the modem to your host’s UART without level translating circuitry. See Table 2 for complete pin description.
6)
Two of the following three pins are all that are required for proper
modem operation: TXD, RXD and DTR. The modem is controlled
by sending it serial commands over TXD and can be monitored by
serial status messages returned on RXD. DTR is optionally used
to reset, terminate calls or return CH2000 to command mode.
8)
7)
9)
The CH2000 must be mounted in the final assembly such
that it is isolated from exposure to any hazardous voltages
within the assembly. Adequate separation and restraint of
cables and cords must be provided.
The circuitry from the CH2000 to the telephone line interface
must be provided in wiring that carries no other circuitry other
than that specifically allowed in the FCC rules (such as A and
A1 leads).
Connection to phone line should be made through an RJ-11
jack.
PCB traces from the modem’s RING and TIP pins to the RJ-11
jack must be 0.1 inch spacing or greater to one another and
0.2 inch spacing or greater to all other traces. The traces
should have a nominal width of 0.020 inches or greater.
The RING and TIP PCB traces should be as short as possible
and oriented to prevent coupling other high speed or high
frequency signals present on the host circuit PCB.
No additional circuitry other than that shown in Figure 6 may
be connected between the modem module and the RJ-11
jack. Doing so will invalidate the FCC approval.
The CH2000, the RJ-11 jack, the interfacing circuitry and all
PCB traces in between, must be contained on a PCB with a
94 V-0 flammability rating.
The supplied FCC registration label must be applied visibly
on the outside of the product.
The product’s User Manual must provide the user with instructions for connection and use as recommended in Section FCC Registration.
All other serial interface lines may be utilized for the convenience
of your application but are not required by the CH2000. Unused
outputs (from modem) should be left unconnected. Unused inputs should be set to the proper logic level. See Table 2.
1999 Cermetek Microelectronics, Inc.
Document No.607-0002 Rev. D (8/99)
7
Figure 6. PSTN Line Interface for CH2000 Products.
CH2000 HANDLING AND ASSEMBLY RECOMMENDATIONS
The CH2000 contains static-sensitive components and should
only be handled by personnel and in areas that are properly protected against static discharge.
There are two mounting techniques that are recommended for
physically connecting the CH2000 to a PCB: 1) sockets, and 2)
direct soldering.
Direct Soldering.
The CH2000 may be wave soldered onto a circuit card. The CH2000
is hermetically sealed and will not be harmed by industry standard
wave soldering processes.
Socketing.
The socketing approach to mounting eliminates cleaning and
desoldering concerns. When the socket is used, it must make a
solid connection to all pins. Failure to do so will cause unreliable
operation. Also, steps should be taken to assure that the module
remains tightly seated in the socket after the end product is shipped.
FCC REGISTRATION
The CH2000 is registered with the FCC (Federal Communications Commission) under Part 68. To maintain the validity of the
registration, you must serve notice to the end user of the product of
several restrictions the FCC places on the CH2000 and its use.
The following notice is recommended and should be included in
the end product’s user manual.
Also, the FCC requires that Cermetek make all repairs to the
CH2000. If repairs are necessary after installation of the CH2000
1999 Cermetek Microelectronics, Inc.
in the end product and the end product has been delivered to the
end user, the end product must be returned to the end product
supplier where the CH2000 can be removed from the end product
and then forwarded to Cermetek for repair.
FOR YOUR USER’S MANUAL
The Part 68 rules require the following (or equivalent) be provided
to the end user of equipment containing a DAA:
Type of Service: The (insert end product name) is designed to be
used on standard device telephone lines. It connects to the telephone line by means of a standard jack called the USOC RJ-11C
(or USOC RJ45S). Connection to telephone-company-provided
coin service (central office implemented systems) is prohibited.
Connection to party lines service is subject to state tariffs.
Changes in Attestation Procedure for Plugs and Jacks:
(Name of applicant) attests that the network interface plugs or
jacks used on this equipment comply with and will continue to
comply with the mechanical requirements specified in Part 68,
Sub-part F, specifically the dimensions, tolerances and metallic
plating requirements. The compliance of these connectors will be
assured by purchase specifications and incoming inspection.
Documentation of such specifications and/or inspections will be
provided by the FCC within 30 days of their request for the same.
Telephone Company Procedures: The goal of the telephone company is to provide you with the best service it can. In order to do
this, it may occasionally be necessary for them to make changes
in their equipment, operations or procedures. If these changes
might affect your service or the operation of your equipment, the
telephone company will give you notice, in writing, to allow you to
make any changes necessary to maintain uninterrupted service.
Document No. 607-0002 Rev. D (8/99)
8
Table 6. CH2000 System Data Mode Compatibility Specifications
P arameter
S p ecificatio n
P a ra m e t e r
S p ecificatio n
2400Hz + 7Hz
1200Hz + 7Hzz
Asynchronous
2400, 1200, 600 bps character
asynchronous. 0-300 bps asynchronous
Recei ve Carri er Frequenci es
V.22 bi s, V.22, 212A
Ori gi nate
Answer
Asynchronous
Speed Range
TXD may di ffer +1%, -2.5% from modem
output. Offsets wi ll be corrected by
addi ng/deleti ng stop bi ts.
Bell 103
Answer 'space'
Answer 'mark'
Ori gi nal 'space'
Ori gi nal 'mark'
Asynchronous
Format
8, 9, 10 bi ts, i ncludi ng start, stop, pari ty
Recei ver
Sensi ti vi ty
OFF to ON threshold-43 dBm
ON to OFF threshold-48 dBm
Telephone Li ne
Interface
Two-wi re full duplex over publi c swi tched
network. On-chi p hybri d and bi lli ng delay
ti mers.
Bi lli ng Delay
2.0 to 3.0 seconds (Ta=25OC)
Modulati on
V.22 bi s, 16 poi nt QAM at 600 baud. V.22
and 212A, 4 poi nt, DPSK at 600 baud.
103 bi nary phase coherent FSK.
Hysteresi s
Self Test
Pattern Generator
Alternate 'ones' and 'zeros' and error
detector, to be used along wi th most
loopbacks. A number i ndi cati ng the bi t
errors detected i s sent to DTE.
Li ne Equali zati on
Fi xed compromi se equali zati on,
transmi t.
Adapti ve equali zer for PSK/QAM,
recei ve.
Di agonosti cs
Avai lable
Local analog loopback.
Local di gi tal loopback.
Remote di gi tal loopback.
Request remote di gi tal loopback.
Local i nterface loopback modem wi th
self test.
Transmi t Carri er
Frequenci es
V.22 bi s, V.22,
212A
Bell 103 mode
Ori gi nate
Answer
1200Hz + 0.1%
2400Hz + 0.1%
Ori gi nate 'space'
Ori gi nate 'mark'
Answer 'space'
Answer 'mark'
1070Hz + .01%
1270Hz + .01%
2020Hz + .01%
2225Hz + .01%
Call Progress
Tones Detected
Computer Interface
In certain circumstances, it may be necessary for the telephone
company to request information from you concerning the equipment which you have connected to your telephone line. Upon
request of the telephone company, provide the FCC registration
number and the ringer equivalence number (REN); both of these
should be less than five in order to assure proper service from the
telephone company. In some cases, a sum of five may not be
useable. Consult your local telephone service provider.
2020Hz + 7Hz
2225Hz + 7Hz
1070Hz + 7Hz
1270Hz + 7Hz
2 dB mi ni mum
Wi th speaker or qui et screen
messages
(no di al tone, busy, ri ng-back, modem
answer tone and voi ce).
IBM PC/XT/AT bus compati ble wi th an
8250/16450/16550A UART as a seri al
controller.
In the event repairs are ever needed on the (insert your product
name), they should be performed by (insert your company name)
or an authorized representative of (insert your company name).
For information contact: (insert your company address).
If Problems Arise: If any of your telephone equipment is not operating properly, you should immediately remove it from your telephone line, as it may cause harm to the telephone network. If the
Telephone Company notes a problem, they may temporarily discontinue service. When practical, they will notify you in advance of
this disconnection. If advance notice is not feasible, you will be
notified as soon as possible. When you are notified, you will be
given the opportunity to correct the problem and informed of your
right to file a complaint with the FCC. Contact your local telephone
service provider if you have any questions about your phone line.
1999 Cermetek Microelectronics, Inc.
Document No.607-0002 Rev. D (8/99)
9
Table 7. CH2000 Electrical Specifications.
Ta=25OC
S ymb o l
V cc
Icc
V OL
V OH
V IL
IIN, ILO
C h a ra c t e ris t ic
S up p ly vo lta g e
M in .
Ty p .
M ax.
U n it s
4.75
5.0
5.25
V
50
40
16
75
mA
mA
mA
0.4
0.26
---
V
V
S up p ly C urre nt
Off ho o k o p e ra ti ng curre nt
On ho o k o p e ra ti ng curre nt
P o we r d o wn o p e ra ti ng curre nt
Outp ut Lo w Vo lta g e ____ ___ __ ___
(IOL=1.6mA ) S LE E P, D S R, D C D , HS , RX D o nly
(IOL=4mA ) V /D
RI (S e e No te 1)
Outp ut Hi g h Vo lta g e ____ ___ __ ___
(IOH=-100uA ) S LE E P, D S R, D C D , HS , RX D
(IOH=-4mA ) V /D
RI (S e e No te 1)
--2.4
4.18
---
---
---
---
V
V
Inp ut Lo w Vo lta g e
D TR, TX D
RX D
0.8
0.95
V
V
Inp ut Le a ka g e C urre nt
TX D , D TR, ______ ____ ____ ___
RX D , RS T, S LE E P, D S R, D C D , HS
100
10
uA
uA
10
pF
CP
C a p a ci ti ve Lo a d
TX D , D TR, RX D
V IH
Inp ut Hi g h Vo lta g e
D TR, TX D
RX D
2.4
3.3
V
V
V T+
RS T (P o si ti ve Hyste re si s Thre sho ld fo r Re se t p i n)
2.7
V
V T-
RS T (Ne g a ti ve Hyste re si s Thre sho ld fo r Re se t p i n)
1.6
V
Note 1: The RI signal can drive a 74HC14 directly to detect ringing over the US ring voltage range. The CH2000 has an internal 30K Ω pullup
resistor on the RI signal. Adding an external pullup resistor to RI will decrease the ring detect sensitivity at low ring voltages. Use of the RI signal to
detect a ring is not required as the modem can be instructed to automatically answer a ring. If TTL compliance is required when used to activate
external circuitry, Cermetek recommends using a Schmitt Trigger or the Envelope Detect Circuit in Figure 4.
DEFAULT STATUS, PERFORMANCE, AND SPECS
The following is a summary of the Default Configuration Profile installed by Cermetek Microelectronics, Inc., prior to delivery of the
CH2000.
Async mode selected
2400bps
Bell 212A operation at 1200bps
Even parity
Auto answer disabled
Command echo ON
All result codes enabled – extended
Wait for dial tone before dialing = 2 seconds
Detects busy signal
Full word result codes
Pulse dial make/break ratio = 39/61
DSR enabled
Modem enabled DTR
DCD enabled
Speaker enabled but off when receiving carrier
Speaker volume set to medium
Local modem will grant RDL request from remote modem
Guard tones disabled
Minimum DTR pulse width = 0.1 seconds
Ring count = 01
1999 Cermetek Microelectronics, Inc.
Escape code character = 43
Carriage return character = 13
Line feed character = 10
Back space character = 8
Duration of wait for dial tone = 2 seconds
Duration of wait for carrier after dialing = 30 seconds
Duration of deal pulse (comma) = 2 seconds
Carrier detect response time = 0.1 seconds
Escape code guard time = 1 second
Length of use after comma = 2.0 seconds
Last carrier to hang up delay = 0.1 seconds
DTMF interdigit delay = 0.1 seconds
DTMF Attenuation = -4dB
Sleep mode inactivity time = 5 seconds
Long space disconnect disabled
Document No. 607-0002 Rev. D (8/99)
10
Table 8. CH2000 Electrical Specifications
P a ra m e te r
M in im u m
Ri ng Vo lta g e S e nsi ti vi ty
Ty p ic a l
M a x im u m U n its
40
V RMS
Re turn Lo ss @ 1000 Hz
17
Ri ng Fre q ue nci e s
C o m m e n ts
dB
15.3
68
Tra nsmi t Le ve l
600 o hm
Hz
-12
dBm
600 o hm - D a ta Mo d e
C o mma nd Mo d e A fte r Re se t
200
mse c
D e la y
Inte r C ha ra cte r D e la y
20
mse c
B e twe e n a ll co mma nd
cha ra cte rs
C o mma nd D e la y
100
mse c
B e twe e n a ll AT
co mma nd s
Mi ni mum Re se t P ulse
10
mse c
If use r sup p li e d
RX A Tra nsmi ssi o n Inse rti o n
Lo ss
-1.5
dBV
Me a sure d fro m A X T to
Ti p /Ri ng p e r Fi g ure 3
RX A Re ce i ve r Inse rti o n Lo ss
-1.0
dBV
Me a sure d fro m
Ti p /Ri ng to A X R p e r
Fi g ure 3
S P K A ud i o Outp ut wi th D C
re fe re nce o f 2.5V +20mV
3.2
V pp
Me a sure d wi th 300
o hm, 0.01uF lo a d
Table 9. Other Performance Specifications
P arameter
Min imu m
DTMF Twist (Balance)
Typ ical Maximu m U n its
3
DTMF Tone Duration
50
Pulse Dialing Rate
10
C o m m e n ts
dB
255
ms
95 ms default
20
pps
10pps default
Pulse Dialing Make/Break
39/61
%
US, Canada default
Pulse Dialing Make/Break
33/67
%
UK, Hong Kong
789 ms default
Pulse Interdigit Interval
700
3000
ms
Call Progress Passband Frequency
120
620
Hz
2
255
sec
Wait Time for Dial Tone
Two seconds default
Table 10. Analog Characteristics
Name
Type
Characteristic
SPK
O (DF)
Minimum Load
300 Ω
Maximum Capacitive Load
0.01µF
Output Impedance
10 Ω
Output Voltage
2.5 + 1.6V
D.C. Offset
<20mV
(with reference to 2.5V nominal)
1999 Cermetek Microelectronics, Inc.
Value
Document No.607-0002 Rev. D (8/99)
11
Table 11. Summary of CH2000 Product Family Options.
M o d el
S u mmary o f F eatu res
CH2000
Full Functi o n, NVRAM, FCC Pa rt 68 Ap p ro ve d , He rme ti c
CH2000ET
Full Functi o n, + Exte nd e d Te mp e ra ture Pe rfo rma nce ,
NVRAM, FCC Pa rt 68 a p p ro ve d , He rme ti c
Notes: 1.
2.
3.
4.
5.
Op eratin g Temp eratu re
0o to 70oC
-40oC to +85oC
All dimensions are in inches.
Case dimensions are nominal + 0.02 inches.
Pin length is nominal + 0.03 inches.
Cermetek reccomends that 0.040 inch diameter plated through holes are used with 0.060 inch diameter pads.
Pin spacings are nominal.
Figure 7. CH2000 Physical Dimensions and Pin Functions.
Cermetek
microelectronics
406 TASMAN DRIVE . SUNNYVALE, CALIFORNIA 94089 . TEL: (408) 752-5000 FAX: (408) 752-5004
E-mail: [email protected]
Website: www.cermetek.com
Cermetek reserves the right to make changes in specifications at any time and without notice. The information furnished by
Cermetek in this publication is believed to be accurate and reliable. However, no responsibility is assumed by Cermetek for its use,
or for any infringements of patents or other rights of third parties resulting from its use. No license is granted under any patents or
patent rights of Cermetek.
Printed in U.S.A.
1999 Cermetek Microelectronics, Inc.
Document No. 607-0002 Rev. D (8/99)
12