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U4285BM Datasheet, PDF (1/10 Pages) TEMIC Semiconductors – AM / FM - PLL
AM / FM - PLL
U4285BM
Description
The U4285BM is an integrated circuit in BICMOS
technology for frequency synthesizers. It performs all the
functions of a PLL radio tuning system and is controlled
by an I2C bus. The device is designed for all frequency
synthesizer applications in radio receivers, as well as
RDS ( Radio Data System ) applications.
Features
D Reference oscillator up to 15 MHz
D Two programmable 16 bit dividers
adjustable from 2 to 65535
D Fine tuning steps:
y AM 1 kHz
y FM 2 kHz
D 4 programmable switching outputs
(open drain up to 15 V)
D Few external component required due to
integrated loop-push-pull stage for AM/FM
D High signal/ noise ratio
Ordering Information
Extended Type Number
U4285BM-AFS
U4285BM-AFSG3
Package
SSO20 plastic
SSO20 plastic
Remarks
Taping according to IEC-286-3
Block Diagram
OSCIN 18
OSCOUT
19
SCL 2
SDA 3
AS 4
Oscillator
I2C bus
interface
FMOSC 9
AMOSC 11
AM/FM
switch
10
GND2
R-divider
SWO1 SWO2 SWO3 SWO4
5678
Switching outputs
Phase
detector
Current
sources
N-divider
1
VDD
Figure 1.
20
GND1
14 PDAM
15 PDAMO
16 VA
17 C
12 PDFMO
13 PDFM
95 10120
TELEFUNKEN Semiconductors
Rev. A3, 14-May-97
1 (10)