U4275B ATMEL Corporation, U4275B Datasheet

no-image

U4275B

Manufacturer Part Number
U4275B
Description
Manufacturer
ATMEL Corporation
Datasheet
Features
Description
The U4275B is a bipolar integrated receiving conditions analyser as well as multipath
noise cancellation circuit. It is designed for high-performance car radio applications.
Block Diagram
Figure 1.
Ordering Information
Preparation of the fieldstrength signal
Detection of multipath and common channel interferences
Evaluation of the receiving conditions by microcomputer
Interrupt output for abruptly occuring interferences
Suitable for analog as well as digital processing
Mute function controllable by microcomputer
Multipath noise cancellation
Only few external components necessary
Extended Type Number
BFSOUT
U4275B-MFLG3
AVFS
CRIN
FSIN
U4275B-MFL
14
1
3
2
Oscillator
Buffer
Filter
FIL19
20
control
MUTE
Multipath
MNC
Common
detector
detector
channel
FIL26
10
19
SO20 plastic
SO20 plastic
MPFIL
Package
CCHFIL
17
18
MPXIN
Interference
Cancellation
Analogue
multiplex
Multipath
interrupt
4
(Gain 1.5)
Reset
Noise
GND2
5
MPXOUT
Taped and reeled
6
VREF
Address
8
logic
Bandgap
GND1
Remarks
16
12
13
15
11
9
7
V
ADDR0
ADDR1
OE
ANAOUT
INT
S
FM Receiving
Condition
Analyzer and
Multipath Noise
Cancellation IC
U4275B
Rev. A3, 16-Oct-01
1 (14)

Related parts for U4275B

U4275B Summary of contents

Page 1

... Mute function controllable by microcomputer • Multipath noise cancellation • Only few external components necessary Description The U4275B is a bipolar integrated receiving conditions analyser as well as multipath noise cancellation circuit designed for high-performance car radio applications. Block Diagram Figure 1. FIL19 20 14 CRIN ...

Page 2

... Ceramic resonator input (456 kHz Output enable for ANAOUT 16 GND1 Ground 17 CCFIL Filter for common channel detection 18 MPFIL Filter for multipath detection 19 FIL26 Filter for 26-kHz detection 20 FIL19 Filter for 19-kHz-Pilot detection U4275B 2 (14 FIL19 FSIN 19 FIL26 2 BFSOUT 18 3 MPFIL AVFS 17 4 CCFIL MPXIN 16 ...

Page 3

... MPXOUT. The MPX signal is blanked out in the event of multipath interference or when MUTE is activated externally in the circuit part MNC (Multipath Noise Canceller). In all other cases, the MPX signal passes through the IC unchanged MPXIN µA BFSOUT 40 µA AVFS MPXOUT 60 k U4275B V S 200 µA 3 (14) ...

Page 4

... GND2 MUTE CRIN ANAOUT U4275B 4 (14) GND2 is the reference potential for the MPX signal. GND2 should be connected directly with the ground terminal of the IF FM demodulator to ensure a high signal–to–noise ratio of the MPX signal. The function unit MNC can be controlled externally via this pin. Blanking occurs when the voltage at the MUTE pin falls below voltage in the range VS/2 > ...

Page 5

... ANAOUT. CCFIL This controller element detects the absolute value of occuring multipath interference. This information is stored in a capacitor which must be connected externally to MPFIL. The capacitor voltage can be interrogated by the system controller via ANAOUT. MPFIL + INT 100 k 100 nA 100 k 100 nA U4275B 5 (14) ...

Page 6

... FIL19 / FIL26 VREF ADDR0 / ADDR1 / OE U4275B 6 (14) In order to differentiate the various types of interferences, the amplitudes of a few spec- tral components of the fieldstrength signal are determined and filtered in FIL19 and FIL26 for further processing. 100 k FIL19 100 nA IF Mute is activated, the reference voltage VREF will apply to the output MPXOUT. A capacitor of 100 nF should be connected at VREF for filtering ...

Page 7

... In order to sup- press this interference systematically first necessary to analyze the received signal so that it is possible to derive the type of interference at any time. The circuit U4275B analyzes the FM reception conditions and makes the data available. This data can be requested by a system controller and evaluated (see figure 1) ...

Page 8

... A voltage proportional to the interference is generated at the filter MPX out Digital or analog signal U4275B processing Interrupt output ANA out AF ...

Page 9

... The common channel detector is blocked for further 20 ms after the detectors are reset to prevent transitory phenomena in the selective filters from causing an indicating error. Figure 4. Symbol amb T stg T j ± V ESD Symbol R thJA U4275B Value Unit 10 V t.b.d. mA -30 to +85 °C t.b.d. °C t.b.d. °C 2000 V Value Unit t.b.d. K/W ...

Page 10

... Interrupt output INT Output voltage Low High Reference voltage VREF Output voltage Analog multiplex output Output voltage Oscillator Input voltage Mute Input voltage Low High *) Type means: A =100% tested 100% correlation tested Characterized on samples Design parameter U4275B 10 (14) Test Conditions Pin Symbol out 2 ...

Page 11

... Interference Common interrupt channel detector Reset Multipath Analogue detector multiplex Multipath MNC Noise control Cancellation (Gain 1. Mute control 560 k 150 nF 1 µF 9 Control signal Address logic 11 Exception quality 7 Supply Bandgap voltage 100 nF MPX - Decoder & audio MPX U4275B 11 (14) ...

Page 12

... Package Information Package SO20 Dimensions in mm 0.4 1. U4275B 12 (14) 12.95 12.70 2.35 0.25 0.10 11. 9.15 8.65 7.5 7.3 0.25 10.50 10.20 technical drawings according to DIN specifications Rev. A3, 16-Oct-01 ...

Page 13

... Class I and II ozone depleting substances in the Clean Air Act Amendments of 1990 by the Environmental Protection Agency (EPA) in the USA 3. Council Decision 88/540/EEC and 91/690/EEC Annex A, B and C (transitional substances) respectively. Atmel Germany GmbH can certify that our semiconductors are not manufactured with ozone depleting substances and do not contain such substances. Rev. A3, 16-Oct-01 U4275B 13 (14) ...

Page 14

Wireless & Microcontrollers Sales Offices A France 3, Avenue du Centre 78054 St.-Quentin-en-Yvelines Cedex Tel: + Fax: + Germany Erfurter Strasse 31 85386 Eching Tel: +49 89 319 70 ...

Related keywords