BUF634_12 Datasheet, PDF (9/20 Pages) Burr-Brown (TI) – 250mA HIGH-SPEED BUFFER

HIGH FREQUENCY APPLICATIONS
The BUF634’s excellent bandwidth and fast slew rate make it
useful in a variety of high frequency open-loop applications.
When operated open-loop, circuit board layout and bypassing
technique can affect dynamic performance.
For best results, use a ground plane type circuit board layout
and bypass the power supplies with 0.1µF ceramic chip
capacitors at the device pins in parallel with solid tantalum
10µF capacitors. Source resistance will affect high-frequency
peaking and step response overshoot and ringing. Best
response is usually achieved with a series input resistor of
25Ω to 200Ω, depending on the signal source. Response
with some loads (especially capacitive) can be improved
with a resistor of 10Ω to 150Ω in series with the output.
V+
C₁₍₁₎
V_IN
OPA
NOTE: (1) C₁ not required
for most common op amps.
Use with unity-gain stable
high speed op amps.
V_O
BUF634
BW
Wide BW mode
(if required)
V–
FIGURE 4. Boosting Op Amp Output Current.
OP AMP
RECOMMENDATIONS
OPA177, OPA1013
OPA111, OPA2111
OPA121, OPA234⁽¹⁾,
OPA130⁽¹⁾
Use Low I_Q mode. G = 1 stable.
OPA27, OPA2107
OPA602, OPA131⁽¹⁾
OPA627, OPA132⁽¹⁾
OPA637, OPA37
Low I_Q mode is stable. Increasing C_L may cause
excessive ringing or instability. Use Wide BW mode.
Use Wide BW mode, C₁ = 200pF. G = 1 stable.
Use Wide BW mode. These op amps are not G = 1
stable. Use in G > 4.
NOTE: (1) Single, dual, and quad versions.
G = +21
V+
250Ω
5kΩ
V_IN ^1µF
OPA132
100kΩ
FIGURE 5. High Performance Headphone Driver.
BUF634
BW
V–
Drives headphones
or small speakers.
R_L = 100Ω
f THD+N
1kHz 0.015%
20kHz 0.02%
+24V
+
10µF
10kΩ
BUF634
10kΩ
C⁽¹⁾
+
12V
–
pseudo
ground
C⁽¹⁾
+
12V
–
NOTE: (1) System bypass capacitors.
FIGURE 6. Pseudo-Ground Driver.
V_IN
I_O = ±200mA
±2V
OPA177
BUF634
Valve
10Ω
FIGURE 7. Current-Output Valve Driver.
1kΩ
9kΩ
10kΩ
10kΩ
1/2
1/2
V_IN
OPA2234
BUF634
Motor
BUF634
OPA2234
±1V
±20V
at 250mA
FIGURE 8. Bridge-Connected Motor Driver.
®
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BUF634