Datasheet

Detailed Description
The MAX7033 CMOS superheterodyne receiver and a few
external components provide the complete receive chain
from the antenna to the digital output data. Depending on
signal power and component selection, data rates as high
as 33kbps Manchester (66kbps NRZ) can be achieved.
The MAX7033 is designed to receive binary ASK data
modulated in the 300MHz to 450MHz frequency range.
ASK modulation uses a difference in amplitude of the car-
rier to represent logic 0 and logic 1 data.
Voltage Regulator
For operation with a single +3.0V to +3.6V supply voltage,
connect AVDD, DVDD, and V
DD5
to the supply voltage.
For operation with a single +4.5V to +5.5V supply voltage,
connect V
DD5
to the supply voltage. An on-chip voltage
regulator drives one of the AVDD pins to approximately
+3.2V. For proper operation, DVDD and both the AVDD
pins must be connected together. Bypass V
DD5
, DVDD,
and the pin 7 AVDD pin to AGND with 0.01μF capacitors,
and the pin 2 AVDD pin to AGND with a 0.1μF capacitor,
all placed as close as possible to the pins.
Low-Noise Amplier
The LNA is an nMOS cascode amplifier with off-chip
inductive degeneration, with a 3.0dB noise figure and an
IIP3 of -12dBm. The gain and noise figures are dependent
on both the antenna matching network at the LNA input
and the LC tank network between the LNA output and the
mixer inputs.
PIN
NAME FUNCTION
TSSOP TQFN
28 28 XTAL2
Crystal Input 2. Can also be driven with an external reference oscillator (see the Crystal
Oscillator section).
—
1, 13,
21, 25
N.C. No Connection
— — EP Exposed Pad (TQFN Only). Connect EP to GND.
LNAOUT MIXIN1 MIXIN2
0˚
90˚
IFIN1MIXOUT IFIN2
RSSI
R
DF2
100kΩ
R
DF1
100kΩ
DIVIDE
BY 64
VCO
LOOP
FILTER
PHASE
DETECTOR
CRYSTAL
DRIVER
POWER-
DOWN
IF LIMITING
AMPS
14
LNASRC
DATA
SLICER
DATA
FILTER
Q
I
AUTOMATIC
GAIN
CONTROL
IMAGE
REJECTION
∑
3.2V REG
24
2
IRSEL
13
5, 10
AVDD
V
DD5
DVDD
DGND
AGND
LNAIN
3
XTALSEL
16
XTAL1
1
XTAL2
28
SHDN
27
DATAOUT
25
DSN
20
DSP
23
DFO
19
PDOUT
26
OPP
21
DFFB
22
4 15 6 8 9 11 12 17 18
AC
÷2
÷1
MAX7033
LNA
7
AVDD
28-PIN TSSOP
PACKAGE
MAX7033 315MHz/433MHz ASK Superheterodyne
Receiver with AGC Lock
www.maximintegrated.com
Maxim Integrated │ 9
Functional Diagram
Pin Description (continued)