Linear Technology DC866 Quick Start Manual

DESCRIPTION
Demonstration circuit 866 is a Quad Video Ampl if ier f ea-
turing the LT6551. The Demo Circuit is designed to oper-
ate f rom a singl e pow er suppl y f rom 4. 5V to 12V. The
inputs and outputs are ac-coupl ed and incl ude 75Ω ter-
minations f or video cabl es. The LT6551 has a f ixed vol t-
PERFORMANCE SUMMARY
Specification s are at T = 25°C
A
SYM BO L PAR AM ETER
V+ Input Suppl y Range
Z Input Impedance
IN
Z Output Impedance
OUT
A Gain
BW Bandw idth
Crosstal k
V Input signal sw ing
IN
I Pow er Suppl y Current
S
OPERATING PRINCIPLES
DC866 provides f our identical channel s of w ideband sig-
nal ampl if ication suitabl e f or driving H DTV or high-
resol ution R G B video displ ay cabl es. Each ampl if ier sec-
tion of the LT6551 provides a f ixed gain of 2, and w ith
series "back-termination" at the outputs (incl uded on the
board), resul ts in unity gain transmission of a video sig-
nal to a destination l oad, w ith f requency response show n
in Figure 2.
Each input is terminated to anal og ground to properl y
l oad the input signal cabl e. AC-coupl ing is provided f or
both inputs and outputs, al ong w ith biasing circuitry, to
provide singl e-suppl y operation. Figure 3 show s the typi-
cal crosstal k betw een adj acent channel s.
age-gain of tw o, thus w ith a terminated output cabl e, the
net gain is nominal l y unity.
Design files for this circuit board are available. Call
the LTC factory.
, LTC and LT are registered trademarks of Linear Technol ogy Corporation. ThinSOT and
Pow erPath are trademarks of Linear Technol ogy Corporation.
CO NDI TI ON S
ac-coupl ed
ac-coupl ed
Output terminated into 75Ω
Output terminated into hi-Z
-3dB, smal l -signal
10M Hz
V+= 5V, no output cl ipping
V+= 9V, no output cl ipping
V+= 5V, no signal
Figure 4 show s the material l ist of the components used
by DC866, and Figure 5 show s the el ectrical interconnec-
tion.
DEMO CIRCUIT 866
QUICK START GUIDE
Quad Video Amplifier
M I N TYP
4. 5 5
75
75
0
+6
60
65
40
LT6551
LT6551
M AX UN I TS
12. 0 V
Ω
Ω
dB
dB
M Hz
dB
±0. 8 V
±1. 5 V
mΑ
1