Overview; Features - Epson S1C05251 Technical Manual

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Overview

The S1C05251 (CAS + FSK IC), an upgraded version of the S1C05250, is a CMOS IC for calling number
identification with the Call Waiting function.
It provides an interface to various call information delivery services based on Bellcore GR-30-CORE, such as CND
(Calling Number Delivery), CNAM (Calling Name Delivery), and CIDCW (Calling Identity on Call Waiting), as
well as British Telecom's CLIP (Calling Line Identification Service) and Cable Communications Association's CDS
(Caller Display Service).
The S1C05251 incorporates power-down, ring detection, and carrier detection circuits, a synchronous receive data
output function, and a clock-synchronized serial interface. All these features make it suitable for various applications
such as those listed below.
• Calling number delivery service with a Call Waiting function
• Telephone sets and similar auxiliary equipment
• Telephone answering equipment
• Multifunction telephones
• Facsimiles
• Computer peripheral circuits
• Message waiting telephones

1.1 Features

• Conforms to Bellcore GR-30-CORE and SR-TSV-002476
• Conforms to British Telecom SIN227 and SIN242
• Can detect Bellcore CPE alert signal (CAS) and British Telecom idle-tone alert signal using a programmable
band-pass filter
(same as S1C05250)
• FSK demodulation circuit based on ITU-T V.23 and BELL202
• Filter bypass mode to detect call progress mode (CPM) signal
• Programmable alert-signal detection level
• Carrier/ring detection output
• FSK energy mode to detect FSK signal in power-down mode
• Supports CAS signal single-end input
• Off-hook detection
(new function for S1C05251)
• Supports 3.57945 MHz crystal oscillator or external clock input
• Serial-receive data output
• Serial host interface
(same as S1C05250)
• Power-down mode
(same as S1C05250)
• Power supply voltage:
• Operating temperature range: -20°C to 70°C
• Current consumption:
• Shipping form: SOP2-28pin package (plastic), DIP-28pin package (ceramic) or chip
S1C05251 TECHNICAL MANUAL
(same as S1C05250)
(same as S1C05250)
(same as S1C05250)
(new function for S1C05251)
(same as S1C05250)
2.7 V to 5.5 V
(same as S1C05250)
(same as S1C05250)
3 mA when operating
1 µA in zero-power mode
6 µA in FSK energy detection mode
(same as S1C05250)
(same as S1C05250)
(same as S1C05250)
(new function for S1C05251)
(same as S1C05250)
(same as S1C05250)
(same as S1C05250)
(new function for S1C05251)
EPSON
1 OVERVIEW
(package for S1C05251)
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