Low Power Ringing SLIC Module QCX601 for Short Loop Access Platforms

Specifications

Low Power Ringing SLIC Module QCX601 for Short Loop Access Platforms

The QCX601 is designed for use short loop “on-premise” applications, such as FCT, FWT, WLL and 
VoIP. In this case power cross and lightning protection is not required. The only protection which 
should be required is for ESD (Electro Static Discharge) caused by handling during installation.

1. Features

 Single supply voltage: +3.3V to +5.0V. 
 Integral high efficiency DC/DC converter. 
 Transformerless 2-wire to 4-wire conversion 
 Integral ringing generator 
 Constant current feed 
Tip/Ring Polarity reversal 
On-hook transmission 
Off-hook detection 
Easy to use, with a minimum number of external components. 
Simplified protection in “on-premise” applications.

2. Applications

 Voice Over Internet Protocol (VoIP) 
Cable Modems 
Key Telephone System 
IP Gateway system 
Wireless Desktop Phone 
Set-top Box System 
Voice Over DSL (VoDSL) 
Short Loop Access Platforms 
Remote Subscriber Units

Other Terminal Adapters

3. Product Selector  

4.Functional Description

 1).Switch Hook Detection

 When the subscriber goes “off-hook” loop current will begin to flow. If this current is above the detection threshold the switch hook output, SHK, will switch to a logic (H). It is recommended that software or hardware de-bouncing of the switch hook signal is used. This is to avoid short pulses which can cause a false switch hook output, triggering the incorrect system response.

During loop disconnect dialling, SHK will pulse between logic (H) and logic (L) to indicate the digits being dialled. Again it is recommended that software de-bouncing of the pulse edges is used to avoid false detection of digits

 2). Tip & Ring Polarity

The QCX601 can reverse the battery voltage polarity at Tip and Ring via the RFL pin. RC and 25HZ is at logic (L):

If RFL is held at logic (H) (Forward) the d.c. voltage at Ring is negative with respect to Tip. If RFL is taken to logic (L) (Reverse) the voltage at Ring is positive with respect to Tip.

The QCX601 is designed for use short loop “on-premise” applications, such as FCT, FWT, WLL and VoIP. In this case power cross and lightning protection is not required. The only protection which should be required is for ESD (Electro Static Discharge) caused by handling during installation.

 3) Ringing Signal Waveforms