DATA BULLETIN
MX469
Features
Selectable Data Rates
1200/2400/4800bps
Full-Duplex MSK
RX and TX Bandpass Filters
Clock Recovery and
Carrier Detect Capabilities
Pin Selected Xtal/Clock Inputs
1.008MHz or 4.032MHz
TX GENERATOR
TX DATA I/P
TX ENABLE
CLOCK RATE
TX FILTER
1200/2400/4800bps MSK Modem
Applications
Radio and General Applications
Data-Over-Radio
PMR/Cellular Signaling
Portable Data Terminals
Personal/Cordless Telephone
MX469P package discontinued
TX SIGNAL O/P
TX SYNC O/P
V
DD
XTAL/CLOCK
CLOCK
OSCILLATOR
XTAL
1200/2400 BPS SELECT
4800 BPS SELECT
BANDPASS O/P
RX ENABLE
RX FILTER
LIMITER
RETRIGGERABLE
MONOSTABLE
DIGITAL
FILTER
DATA
FILTER
LIMITER
UNCLOCKED
DATA O/P
DIVIDER
f
..
V
BIAS
n
V
SS
RX SIGNAL I/P
RECTIFIER
DIGITAL
PLL
DATA
LATCH
CLOCKED
DATA O/P
RX SYNC O/P
NOISE FILTER
RECTIFIER
S/N
COMPARATOR
CARRIER DETECT TIME CONSTANT
CARRIER DETECT O/P
The MX469 is a full-duplex pin-selectable 1200/2400/4800bps Minimum Shift Key (MSK) Modem for FM radio
links. The mark and space frequencies are 1200/1800, 1200/2400, and 2400/4800Hz respectively. Tone
frequencies are phase continuous; transitions occur at the zero crossing point. The use of a common Xtal
oscillator with a choice of two clock frequencies (1.008MHz or 4.032MHz) provides data-rate, transmit
frequencies, and RX/TX synchronization. The transmitter and receiver operate entirely independently
including individual section powersave functions.
The MX469 includes on-chip circuitry for Carrier Detect and RX Clock Recovery, both of which are made
available at output pins. RX, TX, and Carrier Detect circuits contain bandpass filters to provide high quality
signals in their respective paths. The carrier detect time constant is set by an external capacitor, whose value
should be arranged as required to further enhance this product's performance in high-noise environments.
The MX469 demonstrates high sensitivity and good bit-error-rate under adverse signal conditions.
This low-power device requires few external components and is available in the following packages:
24-pin SOIC (MX469DW), 22-pin PDIP (MX469P), and 20-pin SOIC (MX469D3).
1998
MX-COM, Inc.
www.mxcom.com Tel: 800 638 5577 336 744 5050 Fax: 336 744 5054
Doc. # 20480081.010
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
All trademarks and service marks are held by their respective companies.
CMLMICRO [ CML MICROCIRCUITS ]
