
LT6210/LT6211
18
62101fc
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507
●
www.linear.com
LINEAR TECHNOLOGY CORPORATION 2003
LT 0311 REV C • PRINTED IN USA
relaTeD parTs
Typical applicaTion
PART NUMBER DESCRIPTION COMMENTS
LT1252/LT1253/LT1254 100MHz Low Cost Video Amplifiers Single, Dual and Quad Current Feedback Amplifiers
LT1395/LT1396/LT1397 400MHz, 800V/µs Amplifiers Single, Dual and Quad Current Feedback Amplifiers
LT1398/LT1399 300MHz Amplifiers with Shutdown Dual and Triple Current Feedback Amplifiers
LT1795 50MHz, 500mA Programmable I
S
Amplifier Dual Current Feedback Amplifier
LT1806/LT1807 325MHz, 140V/µs Rail-to-Rail I/O Amplifiers Single and Dual Voltage Feedback Amplifiers
LT1815/LT1816/LT1817 220MHz, 1500V/µs Programmable I
S
Operational Amplifier Single, Dual and Quad Voltage Feedback Amplifiers
Figure 5. Line Driver with Low Power Mode
Figure 6. Frequency Response for Full
Speed and Low Power Mode
Line Driver with Power Saving Mode
In applications where low distortion or high slew rate are
desirable but not necessary at all times, it may be possible
to decrease the LT6210 or LT6211’s quiescent current when
the higher power performance is not required. Figure 5
illustrates a method of setting quiescent current with a
FET switch. In the 5V dual supply case pictured, shorting
the I
SET
pin through an effective 20k to ground sets the
supply current to 6mA, while the 240k resistor at the I
SET
pin with the FET turned off sets the supply current to ap-
proximately 1mA. The feedback resistor of 4.02k is selected
to minimize peaking in low power mode. The bandwidth
of the LT6210 in this circuit increases from about 40MHz
in low power mode to over 200MHz in full speed mode,
as illustrated in Figure 6. Other AC specs also improve
significantly at the higher current setting. The following
table shows harmonic distortion at 1MHz with a 2V
P-P
sinusoid at the two selected current levels.
Harmonic Distortion
LOW POWER FULL SPEED
HD2 –53dBc HD2 –68dBc
HD3 –46dBc HD3 –77dBc
–
+
LT6210
R1
240k
R2
22k
R
LOAD
150Ω
V
OUT
6210 F05
–5V
4.02k
HS/LP
V
IN
5V
4
5
2
6
1
3
2N7002
FREQUENCY (MHz)
–4
AMPLITUDE (dB)
–2
–1
1
0 10 100 1000
6210 F06
–6
1
0
–3
–5
2
FULL
SPEED
MODE
I
S
= 6mA
LOW POWER
MODE
I
S
= 1mA
T
A
= 25°C
V
OUT
= 100mV
P-P