U3665M Datasheet, PDF (1/9 Pages) TEMIC Semiconductors – Baseband Delay Line 64 us (Improved Version)

U3665M
Baseband Delay Line 64 ms (Improved Version)
Application
In TV sets, the integrated baseband delay line circuit is suitable for decoders with color-difference signal outputs
Description
The integrated delay line circuit U3665M is suitable for
all chroma decoders with baseband color-difference
outputs. It is suitable for PAL-, SECAM- and
NTSC-signals as well. The U3665M contains two
separate delay lines for processing (R–Y)-output and
(B–Y)-output separately. The delay is performed by inter-
nally switched capacitors. On-chip postfiltering avoids
the need for external filter components. In the case of the
U3665M, the postfilter is tuned to Bessel-characteristic.
A summing circuitry combines the information of
adjacent TV-lines, thus giving an interpolated sum for the
PAL-system, storing preceeding lines for the SECAM-
system and providing a comb-filtered output for
NTSC-signals. Due to internally generated timing,
synchronization is easily done by feeding a line-frequent
impulse (usually the SC-impulse) to the sync-input of
the IC.
Features
D One line delay time, addition of delayed and
non-delayed output signals
D Adjustment-free application, VCO without
external components
D Handles negative or positive color-difference
input signals
D Clamping of AC-coupled input signals
[±(R–Y) and ±(B–Y)]
D Line-locked by the sandcastle pulse
D No crosstalk between SECAM color
carriers (diaphoty)
D Comb-filtering functions for NTSC color-
difference signals
D Correction of phase errors in the PAL system
"(B–Y)
14
"_{(R–Y) 16}
V_{DD2 1}
GND2 3
Clamping
Clamping
Line memory
Shift register
Line memory
Bias
SC detector
5
f_SC
PLL
V_Ref
S+H
+
LPF
" ₁₂ (B–Y)
S+H
+
LPF
" _{11 (R–Y)}
V_Ref
Control
3 MHz
9 ^VDD1
Clock generator
10 ^GND1
SC pulse
Figure 1. Block diagram
94 8846
TELEFUNKEN Semiconductors
1 (9)
Rev. A1, 17-Jul-96
Preliminary Information