LT1223CS8 Linear Technology, LT1223CS8 Datasheet - Page 7

• Manufacturer Part Number: LT1223CS8
• Description: IC CURRNT FEEDBK AMP100MHZ 8SOIC
• Manufacturer: Linear Technology

Specifications of LT1223CS8

• Amplifier Type: Current Feedback
• Number Of Circuits: 1
• Slew Rate: 1300 V/µs
• -3db Bandwidth: 100MHz
• Current - Input Bias: 1µA
• Voltage - Input Offset: 1000µV
• Current - Supply: 6mA
• Current - Output / Channel: 60mA
• Voltage - Supply, Single/dual (±): 8 V ~ 36 V, ±4 V ~ 18 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Output Type: -
• Gain Bandwidth Product: -

APPLICATIO S I FOR ATIO
Current Feedback Basics
The small-signal bandwidth of the LT1223, like all current
feedback amplifiers, isn’t a straight inverse function of the
closed-loop gain. This is because the feedback resistors
determine the amount of current driving the amplifier’s
internal compensation capacitor. In fact, the amplifier’s
feedback resistor (R
works with internal junction capacitances of the LT1223 to
set the closed-loop bandwidth.
Even though the gain set resistor (R
to ground works with R
TYPICAL PERFOR A CE CHARACTERISTICS
–10
–15
–20
–25
–30
–10
20
15
10
–5
10
–2
–4
–6
–8
5
0
8
6
4
2
0
1M
0
Voltage Gain and Phase vs
Frequency
Noninverting Amplifier Settling
Time to 10mV vs Output Step
A = +1
R
V = 15V
R = 1k
F
S
V
L
= 1k
PHASE
±
GAIN
20
R = 100
L
10M
SETTLING TIME (ns)
FREQUENCY (Hz)
40
Ω
R = 100
L
R
U
L
≥
F
TO 10mV
TO 10mV
) from output to inverting input
60
Ω
1k
100M
F
to set the voltage gain just like it
U
R
V = 15V
R
S
L
F
W
≥
= R
LT1223 • TPC20
80
LT1223 • TPC23
±
1k
G
= 1k
U
100
1G
G
W
180
135
225
90
45
0
–45
–90
–135
–180
–225
) from inverting input
–10
10
–2
–4
–6
–8
0.001
8
6
4
2
0
0.01
0.1
0
Noninverting Amplifier Settling
Time to 1mV vs Output Step
U
A = +1
R = 1k
V = 15V
R = 1k
10
S
V
L
F
Total Harmonic Distortion vs
Frequency
V = 15V
V = 7V
R = 400
R
S
O
F
L
±
= R
±
G
RMS
=1k
Ω
100
SETTLING TIME ( s)
FREQUENCY (Hz)
does in a voltage feedback op amp, the closed-loop
bandwidth does not change. This is because the equiva-
lent gain bandwidth product of the current feedback am-
plifier is set by the Thevenin equivalent resistance at the
inverting input and the internal compensation capacitor.
By keeping R
Thevenin resistance changes by the same amount as the
change in gain. As a result, the net closed-loop bandwidth
of the LT1223 remains the same for various closed-loop
gains.
1
1k
TO 1mV
TO 1mV
THD
µ
LT1223 • TPC24
10k
LT1223 • TPC21
F
constant and changing the gain with R
2
100k
–20
–30
–40
–50
–60
–70
–10
10
–2
–4
–6
–8
8
6
4
2
0
1
0
2nd and 3rd Harmonic
Distortion vs Frequency
Inverting Amplifier Settling
Time vs Output Step
V = 15V
V = 2V
R = 100
R
A = 10dB
A = –1
R = 1k
V = 15V
R = 1k
O
S
V
L
F
F
S
V
L
= 1k
TO 10mV
±
±
20
P-P
SETTLING TIME (ns)
FREQUENCY (MHz)
TO 10mV
40
10
TO 1mV
60
LT1223
TO 1mV
3RD
2ND
LT1223 • TPC22
80
LT1223 • TPC25
G
, the
1223fb
7
100
100