AD828
LOW DISTORTION LINE DRIVER
The AD828 can quickly be turned into a powerful, low distor-
tion line driver (see Figure 46). In this arrangement the AD828
can comfortably drive a 75
Ω
back-terminated cable, with a
5 MHz, 2 V p-p input; all of this while achieving the harmonic
distortion performance outlined in the following table.
Configuration
1. No Load
2. 150
Ω
R
L
Only
3. 150
Ω
R
L
7.5
Ω
R
C
2nd Harmonic
–78.5 dBm
–63.8 dBm
–70.4 dBm
1.1k
+V
S
1k
1 F
0.1 F
3
1/2
8
AD828
2
1k
1k
1
R
C
7.5
In this application one half of the AD828 operates at a gain of
2.1 and supplies the current to the load, while the other pro-
vides the overall system gain of 2. This is important for two
reasons: the first is to keep the bandwidth of both amplifiers the
same, and the second is to preserve the AD828’s ability to oper-
ate from low supply voltage. R
C
varies with the load and must
be chosen to satisfy the following equation:
RC = MR
L
,
where
M
is defined by [(M + 1) G
S
= G
D
] and G
D
= Driver's
Gain, G
S
= System Gain.
6
V
IN
5
75
1/2
75
7
1 F
0.1 F
R
L
AD828
4
75
–V
S
Figure 46. Low Distortion Amplifier
OUTLINE DIMENSIONS
Dimensions shown in inches and (mm).
8-Lead Plastic Mini-DIP (N) Package
8-Lead SO (R) Package
0.1968 (5.00)
0.1890 (4.80)
8
PIN 1
1
5
0.25
(6.35)
0.31
(7.87)
8
5
4
4
0.30 (7.62)
REF
0.035 0.01
(0.89 0.25)
0.1574 (4.00)
0.1497 (3.80)
PIN 1
1
0.2440 (6.20)
0.2284 (5.80)
0.39 (9.91) MAX
0.165 0.01
(4.19 0.25)
0.125
(3.18)
MIN
0.018 0.003 0.10
(0.46 0.08) (2.54)
BSC
0.033
(0.84)
NOM
0.0500 (1.27)
BSC
0.0098 (0.25)
0.0040 (0.10)
SEATING
PLANE
0.0688 (1.75)
0.0532 (1.35)
0.0192 (0.49)
0.0138 (0.35)
8
0.0098 (0.25) 0
0.0075 (0.19)
0.0196 (0.50)
0.0099 (0.25)
45
0.18 0.03
(4.57 0.76)
0.011 0.003
(0.28 0.08)
15
°
0.0500 (1.27)
0.0160 (0.41)
SEATING
PLANE
0
°
–12–
REV. B
PRINTED IN U.S.A.
C1823a–0–6/00 (rev. B) 00879
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