LT6552
11
6552f
APPLICATIO S I FOR ATIO
WU
U
Figure 3
7
6
LT6552
4
1
8
VO
+
3
–
2
VINDIFF
SHDN
5
VO = (VINDIFF + VDC)
RF + RG
RG
RF
6552 F01
VDC
REF
FB
RG
V +
7
6
LT6552
4
1
8
VO
+
3
–
2
VIN
SHDN
5
VO = –
RF + RG
RG
VO = +
RF + RG
RG
RF
SHDN
RF + RG
RG
RF
RG
6552 F01
7
6
LT6552
4
REF
1
FB
8
VO
+
3
–
2
5
VO =
RF
7
6
LT6552
4
1
8
VO
+
3
–
2
VIN
SHDN
5
RF
VIN
(
VINDIFF –VIN
VIN
( (
REF
FB
REF
FB
RG
VINDIFF
RG
V +
V–
Figure 4
The LT6552 is a video difference amplifier with two pairs
of high impedance inputs. The primary purpose of the
LT6552 is to convert high frequency differential signals
into a single-ended output, while rejecting any common
mode noise. In the simplest configuration, one pair of
inputs is connected to the incoming differential signal,
while the other pair of inputs is used to set amplifier gain
and DC level. The device will operate on either single or
dual supplies and has an input common mode range
which includes the negative supply. The common mode
rejection ratio is greater than 60dB at 10MHz. Feedback is
applied to Pin 8 and the LT6552’s transient response is
optimized for gains of 2 or greater.
Figure 3 shows the single supply connection. The ampli-
fier gain is set by a feedback network from the output to
Pin 8 (FB). A DC signal applied to Pin 1 (REF) establishes
the output quiescent voltage and the differential signal is
applied to Pins 2 and 3.
Figure 4 shows several other connections using dual
supplies. In each case, the amplifier gain is set by a
feedback network from the output to Pin 8 (FB).