Rainbow Electronics MAX2442 - Manual

General Description
The MAX2440/MAX2441/MAX2442 highly integrated
front-end receiver ICs provide the lowest cost solution for
cordless phones and ISM-band radios operating in the
900MHz band. All devices incorporate receive image-
reject mixers to reduce filter cost. They operate with a
+2.7V to +4.8V power supply, allowing direct connection
to a 3-cell battery stack.
The signal path incorporates an adjustable-gain LNA
and an image-reject downconverter with 35dB image
suppression. These features yield excellent combined
downconverter noise figure (4dB) and high linearity with
an input third-order intercept point (IP3) of up to +2dBm.
All devices include an on-chip local oscillator (LO),
requiring only an external varactor-tuned LC tank for
operation. The integrated divide-by-64/65 dual-modulus
prescaler can also be set to a direct mode, in which it
acts as an LO buffer amplifier. Three separate power-
down inputs can be used for system power manage-
ment, including a 0.5µA shutdown mode. These parts
are compatible with commonly used modulation
schemes such as FSK, BPSK, and QPSK, as well as fre-
quency hopping and direct sequence spread-spectrum
systems. All devices come in a 28-pin SSOP package.
Evaluation kits are available for the MAX2420/
MAX2421/MAX2422. The MAX2420/MAX2421/MAX2422
are transceivers whose receive sections and pinout are
identical to the MAX2440/MAX2441/MAX2442.
For complete transceiver devices, refer to the MAX2420/
MAX2421/MAX2422/MAX2460/MAX2463 and MAX2424/
MAX2426 data sheets.
________________________Applications
Cordless Phones Spread-Spectrum Communications
Wireless Telemetry Two-Way Paging
Wireless Networks
Features
♦ Receive Mixer with 35dB Image Rejection
♦ Adjustable-Gain LNA
♦ Up to +2dBm Combined Receiver Input IP3
♦ 4dB Combined Receiver Noise Figure
♦ Low Current Consumption:
23mA Receive
9.5mA Oscillator
♦ 0.5µA Shutdown Mode
♦ Operates from Single +2.7V to +4.8V Supply
MAX2440/MAX2441/MAX2442
900MHz Image-Reject Receivers
________________________________________________________________ Maxim Integrated Products 1
28
27
26
25
24
23
22
21
20
19
18
17
16
15
1
2
3
4
5
6
7
8
9
10
11
12
13
14
GND
GND
GND
TANK
GND
PREOUT
PREGND
MOD
DIV1
VCOON
RXON
GND
GND
GND
LNAGAIN
GND
GND
GND
RXIN
GND
RXOUT
CAP1
SSOP
TOP VIEW
MAX2440
MAX2441
MAX2442
TANK
V CC
V CC
V
CC
V CC
V CC
___________________Pin Configuration
19-1352; Rev 2; 12/00
PART
MAX2440EAI
MAX2441EAI
MAX2442EAI -40°C to +85°C
-40°C to +85°C
-40°C to +85°C
TEMP. RANGE PIN-PACKAGE
28 SSOP
28 SSOP
28 SSOP
_______________Ordering Information
Functional Diagram appears at end of data sheet.
High side
INJECTION
TYPE
f RF + 10.7
LO FREQ
(MHz)
High side
High side
f RF + 70
f RF + 46
MAX2442
MAX2441
70
46
MAX2440
PART
10.7
IF FREQ
(MHz)
______________________Selector Guide
EVALU
ATION
KIT
AVAILA
BLE
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.