SHC615 Datasheet, PDF (17/19 Pages) Burr-Brown (TI) – Wide-Bandwidth, DC RESTORATION CIRCUIT

• Make short, low-inductance traces. The entire physical
circuit should be as small as possible.
• Use a low-impedance ground plane on the component side
to ensure that a low-impedance ground is available through-
out the layout.
• Do not extend the ground plane under high-impedance
nodes sensitive to stray capacitances such as the amplifier’s
input terminals.
• Sockets are not recommended since they add significant
inductance and parasitic capacitance. If sockets are re-
quired, use zero-profile sockets.
• Use low-inductance, surface-mount components. Surface-
mount components offer the best AC performance.
• A resistor of 100 to 250Ω in series with the high-imped-
ance inputs is recommended to reduce peaking.
• Plug-in prototype boards and wire-wrap boards will not
function well. A clean layout using RF techniques is
essential—there are no shortcuts.
• Terminate transmission line loads. Unterminated lines,
such as box cables, can appear to the amplifier to be a
capacitive or inductive load. By terminating a transmission
line with its characteristic impedance, the amplifier’s load
then appears purely resistive.
• Protect the hold control input with an external diode if
necessary.
C_HOLD
R_B
(25Ω to 200Ω)
9 GND
4
3 Base
2
Emitter
(20Ω
to
200Ω)
Hold ⁷
Control
S/H In+
10
S/H In–
11
Switching Stage
Sampling Comparator
(SC)
SOTA
NOTE: (1) ±V_CC = ±6V absolute max.
+
2.2µF
OTA
12 _Collector
Biasing
1 ^{IQ Adjust}
13
+V_CC
+5V⁽¹⁾
5
–V_CC
–5V⁽¹⁾
R_Q
R_Q = 300Ω sets roughly
I_Q = ±14mA
10nF 470pF
470pF
10nF 2.2µF
+
Solid Tanatlum
FIGURE 6. Basic Connections
®
17
SHC615