Rainbow Electronics MAX7044 - Manual

General Description
The MAX7044 crystal-referenced phase-locked-loop
(PLL) VHF/UHF transmitter is designed to transmit
OOK/ASK data in the 300MHz to 450MHz frequency
range. The MAX7044 supports data rates up to 100kbps,
and provides output power up to +13dBm into a 50Ω
load while only drawing 7.7mA at 2.7V.
The crystal-based architecture of the MAX7044 elimi-
nates many of the common problems with SAW-based
transmitters by providing greater modulation depth,
faster frequency settling, higher tolerance of the trans-
mit frequency, and reduced temperature dependence.
The MAX7044 also features a low supply voltage of
+2.1V to +3.6V. These improvements enable better
overall receiver performance when using the MAX7044
together with a superheterodyne receiver such as the
MAX1470 or MAX1473.
A simple, single-input data interface and a buffered
clock-out signal at 1/16th the crystal frequency make
the MAX7044 compatible with almost any microcon-
troller or code-hopping generator.
The MAX7044 is available in an 8-pin SOT23 package
and is specified over the -40°C to +125°C automotive
temperature range.
Applications
Remote Keyless Entry (RKE)
Tire-Pressure Monitoring (TPM)
Security Systems
Garage Door Openers
RF Remote Controls
Wireless Game Consoles
Wireless Computer Peripherals
Wireless Sensors
Features
♦ +2.1V to +3.6V Single-Supply Operation
♦ OOK/ASK Transmit Data Format
♦ Up to 100kbps Data Rate
♦ +13dBm Output Power into 50Ω Load
♦ Low 7.7mA (typ) Operating Supply Current*
♦ Uses Small, Low-Cost Crystal
♦ Small 3mm x 3mm 8-Pin SOT23 Package
♦ Fast-On Oscillator: 250µs Startup Time
* At 50% duty cycle (315MHz, 2.7V supply, +13dBm
output power)
MAX7044
300MHz to 450MHz High-Efficiency,
Crystal-Based +13dBm ASK Transmitter
________________________________________________________________ Maxim Integrated Products 1
DATA
CLKOUT PAOUT
1
2
8
7
XTAL2
V DD GND
PAGND
XTAL1
SOT23
TOP VIEW
3
4
6
5
MAX7044
Pin Configuration
Ordering Information
MAX7044
1
XTAL1
ANTENNA
3.0V
3.0V
680pF 220pF 100nF
100nF
XTAL2
f XTAL
8
2
GND V DD
7
3
PAGND DATA INPUT
CLOCK
OUTPUT
(f CLKOUT =
f XTAL /16)
DATA
6
4
PAOUT CLKOUT
5
Typical Application Circuit
19-3221; Rev 0; 1/04
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
EVALUATION KIT
AVAILABLE
PART TEMP RANGE
PIN-
PACKAGE
TOP MARK
MAX7044AKA-T -40°C to +125°C 8 SOT23-8 AEJW