MX631 Datasheet, PDF (1/9 Pages) CML Microcircuits – LOW VOLTAGE SPM DETECTOR

DATA BULLETIN
MX631 LOW VOLTAGE SPM DETECTOR
Features
• Detects 12 & 16kHz SPM Frequencies
• Low Power (3.0 Volt_MIN <1.0mA) Operation
• High Speechband Rejection Properties
• Tone-Follower and Packet Mode Outputs
• Applications
•Complex and/or Simple Telephone Systems
•Call-Charge/-Logging Systems
MX631DW
16-Pin SOIC
MX631P
16-Pin PDIP
XTAL/CLOCK
XTAL/CLOCK
OSCILLATOR
XTAL
CLOCK
CLOCK IN
OUT
CLOCK
V_SS
DIVIDERS
SYSTEM
V_DD
SYSTEM
(12kHz/16kHz)
SIGNAL
IN (-)
SIGNAL
IN (+)
AMP OUT
INPUT AMP
-
+
12kHz/16kHz
+20dB
LEVEL DETECTOR
32
1
DIVIDER
V_BIAS
Figure 1 - Functional Block Diagram
TONE FOLLOWER
OUTPUT
TONE
FOLLOWER
LOGIC
PERIOD
MEASURE
SYSTEM
PACKET MODE
OUTPUT
PACKET
TONE
LOGIC
Description
The MX631 is a low-power, system-selectable
Subscriber Pulse Metering (SPM) detector that indicates
the presence of both 12kHz or 16kHz telephone call-
charge frequencies on a telephone line.
Deriving its input directly from the telephone line,
input amplitude/sensitivities are component adjustable
to the user's national ‘Must/Must-Not Decode’
specifications via an on-chip input amplifier, while the
12kHz and 16kHz frequency limits are accurately
defined by the use of an external 3.579545MHz
telephone-system Xtal or clock-pulse input.
The MX631, which demonstrates high 12kHz and
16kHz performance in the presence of both voice and
noise, can operate from either a single or differential
analog signal input from which it will produce two
individual logic outputs:
1. Tone Follower Output - A 'tone-following' logic
output producing a “Low” level for the period of a
correct decode and a “High” level for a bad decode
or NOTONE.
2. Packet (Cumulative Tone) Mode Output - To
respond and/or de-respond after a cumulative
40ms of good tone (orNOTONE) in any 48ms period.
This process will ignore small fluctuations or fades
of a valid frequency input and is available for
µProcessor ‘Wake-Up’, Minimum Tone detection,
NOTONE indication or transient avoidance.
This system (12kHz/16kHz) selectable integrated
circuit, which may be line-powered, is available in 16-pin
plastic DIP and SOIC surface mount packages.
© 1997 MX•COM, INC.
www.mxcom.com Tele: 800 638 5577 910 744 5050 Fax: [phone]
Doc.# 20480087.003
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
All trademarks and service marks are held by their respective companies