NJM2590/97

-1-

Ver.2004-08-25

455kHz INPUT FM IF DEMODULATOR

GENERAL DESCRIPTION

PACKAGE OUTLINE

The NJM2590 and NJM2597 are low current FM IF demodulator

ICs with 455kHz IF input, which operate from 1.6V supply.

The NJM2590/97 contain the minimum functions required to

FM IF demodulator, that is, IF amplifier, quadrature detector,

LPF amplifier, FSK comparator, RSSI, and RSSI comparator.

It offers unmatched design flexibility.

FEATURES

Low Operating Voltage

1.6V to 5.5V

Low Operating Current

IF Input Frequency

455kHz (standard)

RSSI Comparator

The Range of Linear Area on RSSI Output versus IF Input Characteristics

NJN2590

IF Input level=25 to 60 dBuVEMF (reference value)

NJM2597

IF Input level=35 to 85 dBuVEMF (reference value)

Bipolar Technology

Package Outline

SSOP14

BLOCK DIAGRAM

NJM2590V/97V

V

+

IF IN

14

13

12

11

10

9

8

1

2

4

3

5

6

7

QUAD DET

RSSI

FSK

OUT

CHARGE

GND

DEC

FSK

REF

QUAD

IN

AF

OUT

LPF

IN

LPF

OUT

LPF

RSSI

OUT

RSSI

COMP

SENSE

LEVEL

CARRIER

SENSE

CHARGE

IF AMP

FSK

COMP