CH1817D Datasheet
Family Of Low Profile DAA Module
Download: CH1817D Datasheet 
CH1817D
Family Of Low Profile DAA Module
CH1817
Family of Low Profile DAA Modules
Introduction The Ch1817 Is A Family Of Low Profile Data Access Arrangement (daa) Modules. They Are
Compatible With All Modem Chip Sets. These Devices Have Been Tested To Meet Or Exceed Fcc Part 68
Requirements And Are Canadian Doc Approvable. They Are Also Recognized By Underwriters Laboratories
to UL 1459 Specifications.
The Ch1817 Modules Are Ultra Small (1.0" X 1.0" X0.35") Affording An Easy Integration Into
Spacesensitive Designs, Including Laptop And Hand-held Computer Based Products. The Ch1817 Family Of
Products May Be Socketed Or Mounted Directly Onto A Printed Circuit Board (pcb). The Telephone Line
connection is made through TIP and RING to an RJ-11 jack or equivalent.
The Ch1817 Is Intended For Use With Fax/modem Chip Sets That Have A Data Throughput Of Up Through
V.32bis. For High Speed
Applications, Cermetek recommends the CH1837A.
FEATURES
Low Profile, Ultra small size: 1.0" x 1.0" x 0.35"
Complete DAA function
Ring detection
Built-in 2-wire to 4-wire conversion
Lightweight
Multimedia compatible
+5V operation
1000 VAC isolation
800 Volt surge protection
V.32bis/14,400bps,
Applications
UL1459 recognized
CH1817-L: Low power consumption and Common
mode noise rejection filter
CH1817-LM (special order): Reduced transmit
attenuation
CH1817-D: Differential transmission input and 0dB
transmission insertion loss.
FUNCTIONAL
Description Ring Detection. Referring To The Block Diagram In Figure 1, Incoming Ring Detection Is
Performed By The Ch1817 And The Ri Pin Is Set Low During The 2 Second (typical) Ring Period And Is
Restored To High For The 4 Seconds (typical) Between Rings. During Incoming Ring Signal Activity,
The Ri Output Is Pulsed At The Same Frequency As The Ringing Signal, Typically 20hz. Figure 2
Contains Additional External Circuitry Which May Be Used To Provide An Envelope Indication Of The
Ring Signal. The Internal Ring Detection Circuit Is Designed To Deter False Indications Due To Pulse
dialing or noise on the line.
The Ri Output Of The Ch1817 Is Diode Protected. Therefore, An External Pull-up Resistor (r>100kohm)
To +5v May Be Utilized To Activate The Ring Detection Circuit When The Ch1817 Is Not Connected To
Power. This Can Be Handy In Designs Where Power Consumption Is Of Concern. When Circuited In This
manner, there is virtually no current draw until a ring signal is present.
Ri Output: Active Low Opto Coupler, 30k Pull-up Square Wave: 15-68hz (typ. 20hz) Sensitivity:
38Vrms across Tip & Ring
VCC ISOLATION
SURGE AND
PROTECTION CIRCUITRY
TIP RING
RCV RI
HYBRID 2W/4W CONVERTER
CH1817D Datasheet
Family Of Low Profile DAA Modules
Download: CH1817D Datasheet
CH1817D
Family Of Low Profile DAA Modules
CH1817
Introduction The Ch1817 Is A Family Of Low Profile Data Access Arrangement (daa) Modules. They Are
Compatible With All Modem Chip Sets. These Devices Have Been Tested To Meet Or Exceed Fcc Part 68
Requirements And Are Canadian Doc Approvable. They Are Also Recognized By Underwriters Laboratories
to UL 1459 Specifications.
The Ch1817 Modules Are Ultra Small (1.0" X 1.0" X0.35") Affording An Easy Integration Into
Spacesensitive Designs, Including Laptop And Hand-held Computer Based Products. The Ch1817 Family Of
Products May Be Socketed Or Mounted Directly Onto A Printed Circuit Board (pcb). The Telephone Line
connection is made through TIP and RING to an RJ-11 jack or equivalent.
The Ch1817 Is Intended For Use With Fax/modem Chip Sets That Have A Data Throughput Of Up Through
V.32bis. For High Speed
Applications, Cermetek recommends the CH1837A.
FEATURES
Low Profile, Ultra small size: 1.0" x 1.0" x 0.35"
Complete DAA function
Ring detection
Built-in 2-wire to 4-wire conversion
Lightweight
Multimedia compatible
+5V operation
1000 VAC isolation
800 Volt surge protection
V.32bis/14,400bps,
Applications
UL1459 recognized
CH1817-L: Low power consumption and Common
mode noise rejection filter
CH1817-LM (special order): Reduced transmit
attenuation
CH1817-D: Differential transmission input and 0dB
transmission insertion loss.
FUNCTIONAL
Description Ring Detection. Referring To The Block Diagram In Figure 1, Incoming Ring Detection Is
Performed By The Ch1817 And The Ri Pin Is Set Low During The 2 Second (typical) Ring Period And Is
Restored To High For The 4 Seconds (typical) Between Rings. During Incoming Ring Signal Activity,
The Ri Output Is Pulsed At The Same Frequency As The Ringing Signal, Typically 20hz. Figure 2
Contains Additional External Circuitry Which May Be Used To Provide An Envelope Indication Of The
Ring Signal. The Internal Ring Detection Circuit Is Designed To Deter False Indications Due To Pulse
dialing or noise on the line.
The Ri Output Of The Ch1817 Is Diode Protected. Therefore, An External Pull-up Resistor (r>100kohm)
To +5v May Be Utilized To Activate The Ring Detection Circuit When The Ch1817 Is Not Connected To
Power. This Can Be Handy In Designs Where Power Consumption Is Of Concern. When Circuited In This
manner, there is virtually no current draw until a ring signal is present.
Ri Output: Active Low Opto Coupler, 30k Pull-up Square Wave: 15-68hz (typ. 20hz) Sensitivity:
38Vrms across Tip & Ring
VCC ISOLATION
SURGE AND
PROTECTION CIRCUITRY
TIP RING
RCV RI
HYBRID 2W/4W CONVERTER
OFF-HOOK SWITCH