NJM2592
Under Development
470MHz INPUT 455kHz FM IF DEMODULATOR
GENERAL DESCRIPTION
The
NJM2592
is a low-voltage, low-current FM IFdemodulator IC
with 455kHz(standard) IF frequency. It includes an oscillator, mixer,
limiting amplifier, quadrature detector,active filter, and FSK comparator.
The
NJM2592
also has a RSSI circuit and RSSI comparator for
carrier sense.
PACKAGE OUTLINE
FEATURES
Low Operating Voltage
1.8V to 5.5V
Low Operating Current
3.5mA at V
+
=2.0V
Operating Frequency
up to 470MHz (reference value)
IF Input Frequency
455kHz (standard)
Ceramic Discriminator or LC resonant Circuit
FSK Comparator with Open-collector Output
Quick Charge /Discharge Circuit for FSK Reference Voltage
Bipolar Technology
Package Outline
SSOP20
NJM2592V
BLOCK DIAGRAM
MIX
IN
20
SENSE RSSI
CARRIER
FSK
CHARGE
LPF
SW
OUT
GND LEVEL OUT SENSE OUT
19
18
17
16
15
14
13
LPF
IN
12
AF
OUT
11
MIXER
RSSI COMP FSK COMP
BUFFER
FILTER AMP
RSSI
CHARGE
QUAD
DET
OSC
IFAMP
IF AMP
1
OSC
(B)
2
OSC
(E)
3
MIX
OUT
4
V+
5
IF
IN
6
DEC
7
FSK
REF
8
NC
9
IF
OUT
10
QUAD
IN
Ver.2003-05-15
-1-