U2860B-M Datasheet, PDF (1/14 Pages) ATMEL Corporation – Dual-Channel FM Sound Demodulator for TV Systems

Features
• Two Alignment-free PLL FM Demodulators, Automatic Lock-in on the Received Sound
Carrier Frequency
• Mono and Dual Channel Application
• Sound IF Inputs Provided for Ceramic Filters
• Automatic Mute for Second Sound Channel (Squelch)
• Mute Function for Both Sound Channels
• 5-V Supply Voltage, Low-power Consumption
• Few External Components
Description
The U2860B-M is a dual-channel FM sound demodulator realized with Atmel ’s
advanced bipolar process. All TV FM standards, from 4.5 MHz up to 6.5 MHz
(standard M, B/G, I, D/K) can be processed with high performance. The circuit is
alignment-free and has a minimum number of external components. With 5 V supply
voltage, the U2860B-M is suitable for TV, VCR and multimedia applications.
Dual-Channel
FM Sound
Demodulator for
TV Systems
U2860B-M
Figure 1. Block Diagram
V_S
13
C_stab
12 11
Supply
V_in1
1
VCO 1
Loop
filter 1
Mute
3
Mute
VCO
offset
V_in2
14
VCO 1
Loop
filter 2
Squelch
4
Squelch
Squelch (second carrier)
8
7
V_AF1
10 ^{VCO offset}
R_ref
(optional)
6
V_AF2
9
Rev. 4794A–TVVCR–02/04