Single-Ended to Differential Conversion/Amplifi cation
n
Low Voltage, Low Noise, Differential Signal
Processing
n
Common Mode Voltage Translation
DESCRIPTION
The LTC®6601-1 is a very easy-to-use fully differential
2nd order active RC fi lter and driver. On-chip resistors,
capacitors, and amplifi er bandwidth are trimmed to provide
consistent and repeatable fi lter characteristics.
The fi lter characteristics are pin-strap confi gurable. Cutoff
frequencies range from 5MHz to 28MHz. Gain is pin-strap
programmable between –17dB and +17dB.
A three-state BIAS pin is provided to adjust amplifi er
power consumption. Select between high performance,
low power (50% power reduction), and standby modes
with the BIAS pin.
The LTC6601-1 is available in a compact 4mm × 4mm
16-pin leadless QFN package.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
Protected by U.S. Patents including 6271719.
TYPICAL APPLICATION
19MHz, 2nd Order Lowpass Filter. Gain = 6dB
2019181716
LTC6601-1
1
+
V
IN
–
2
3
3V
4
5
+
–
678910
15
14
13
12
11
66011 TA01a
0.1µF
3V
0.1µF
Frequency Response
10
5
0
–
V
OUT
+
–5
–10
GAIN (dB)
–15
–20
–25
–30
110100
FREQUENCY (MHz)
66011 TA01b
66011f
1
LTC6601-1
(Note 1)
Total Supply Voltage (V+ to V–) ...............................5.5V
+
Input Voltage (Any Pin) (Note 2) ..V
Input Current (V
, BIAS) ..................................±10mA
OCM
+ 0.3V to V– –0.3V
Input Current (Pins 1, 5) (Note 2) ........................±20mA
Input Current (Pins 2, 4) (Note 2) ........................±30mA
Input Current (Pins 6, 20) (Note 2) ......................±15mA
Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi ed by a label on the shipping container.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifi cations, go to: http://www.linear.com/tapeandreel/
DC ELECTRICAL CHARACTERISTICS
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at TA = 25°C. V+ = 3V, V– = 0V, V
I
LOAD
(V
OUT
= 0, R
+
+ V
= 100k. The fi lter is confi gured for a gain of 1 unless otherwise noted. VS is defi ned as (V+ – V–). V
BAL
–
OUT
)/2. V
is defi ned as (V
INCM
INP
+ V
INM
)/2. V
is defi ned as (V
OUTDIFF
INCM
OUT
+
= V
– V
= mid-supply, BIAS tied to V+ or fl oating,
OCM
OUT
–
). V
is defi ned as (V
INDIFF
is defi ned as
OUTCM
– V
INP
INM
). See
Figure 1.
SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITS
(Note 6)Amplifi er Differential Offset Voltage (Input
V
OSDIFF
Referred)
ΔV
OSDIFF
/ΔT
(Note 6)
R
(Note 14)Input Resistance, BIAS = V
IN
Ampifi er Differential Offset Voltage Drift
(Input Referred)
Single Ended Input Resistance, Pin 2 or Pin 4
Differential Input Resistance
VS = 2.7V to 5.25V, BIAS = V
+
BIAS = Floating
= 2.7V to 5.25V1µV/°C
V
S
+
VS = 3V
V
= 3V
S
l
l
±0.25
±0.25±1±1.5
133
200
mV
mV
2
66011f
LTC6601-1
DC ELECTRICAL CHARACTERISTICS
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
I
LOAD
(V
OUT
= 0, R
+
+ V
= 100k. The fi lter is confi gured for a gain of 1 unless otherwise noted. VS is defi ned as (V+ – V–). V
BAL
–
OUT
)/2. V
is defi ned as (V
INCM
INP
+ V
= 25°C. V+ = 3V, V– = 0V, V
A
INM
)/2. V
is defi ned as (V
OUTDIFF
Figure 1.
SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITS
ΔR
(Note 14)
IN
(Note 7)Internal Amplifi er Input BiasVS = 2.7V to 5V BIAS = V
I
B
(Note 7)Internal Amplifi er Input OffsetVS = 2.7V to 5V BIAS = V
I
OS
V
(Note 8)Input Signal Common Mode Range
INCM
CMRRI
(Notes 9, 14)
CMRRO
(Notes 9, 14)
Input Resistance Match, BIAS = V
Single Ended Input Resistance, Pin 2 or Pin 4 VS = 3V
(V
+ V
INM
+
+
, V
, V
)/2
OCM
OCM
= 1.5V
= 2.5V
OCM
OCM
= 1.5V
= 2.5V
INP
BIAS = V
BIAS = V
BIAS Pin Floating, V
BIAS Pin Floating, V
Input Common Mode Rejection Ratio
(Amplifi er Input Referred) ΔV
ΔV
= 2.5VVS = 5V74dB
INCM
Output Common Mode Rejection Ratio
(Amplifi er Input Referred) ΔV
ΔV
= 1VVS = 5V70dB
OCM
PSRR (Note 10)Power Supply Rejection Ratio
(Amplifi er Input Referred) ΔVS/ΔV
BIAS = V
+
BIAS Pin Floating
PSRRCM (Note 10) Common Mode Power Supply Rejection Ratio
(ΔV
/ΔV
S
g
cm
Common Mode Gain (ΔV
ΔV
OCM
)V
OSCM
= 2V
Common Mode Gain Error = 100 • (gcm – 1)
ΔV
= 2VVS = 5V
OCM
BAL
Output Balance (ΔV
OUTCM
Single-Ended Input
Differential Input
V
OSCM
ΔV
OSCM
V
OUTCMR
R
INVOCM
V
MID
/ΔT
(Note 8)Output Signal Common Mode Range
Common Mode Offset Voltage
(V
– V
OUTCM
OCM
)
Common Mode Offset Voltage Drift
(V
– V
OUTCM
(Voltage Range for the V
Input Resistance, V
Voltage at the V
)
OCM
OCM
PinVS = 3V
OCM
PInVS = 3V
OCM
+
BIAS = Floating
BIAS = Floating
= 3V
V
S
V
= 5V
S
= 3V
V
S
V
= 5V
S
/ΔV
INCM
OSDIFF
/ΔV
OCM
OSDIFF
OUTCM
/ΔV
OSDIFF
/ΔV
OUTDIFF
OCM
)
)
= 2.7V to 5V
V
S
V
= 2.7V to 5V
S
= 2.7V to 5V
S
= 5V1V/V
V
S
ΔV
V
V
V
= 2V
OUTDIFF
= 5V
S
= 5V
S
= 2.7V to 5V BIAS = V
S
VS = 2.7V to 5V BIAS = Floating
= 2.7V to 5V BIAS = V
V
S
VS = 2.7V to 5V BIAS = Floating
Pin)VS = 3V BIAS = V
VS = 5V BIAS = V
VS = 3V BIAS Pin Floating
V
= 5V BIAS Pin Floating
S
INCM
OUT
+
= V
– V
= mid-supply, BIAS tied to V+ or fl oating,
+
+
+
+
+
+
OCM
OUT
–
). V
is defi ned as (V
INDIFF
l
l
–50
l
–25
l
l
l
l
l
l
l
66
l
60
l
4660dB
l
l
l
l
l
l
l
l
1.1
l
1.1
l
1.1
l
1.1
l
12.51823.5kΩ
l
1.4751.51.525V
±0.25
–25
–12.5
0
0
0
0
±0.1±0.3%
–62
–63
OUTCM
INP
±1
±1
95
95
±5
±8
5
20
is defi ned as
– V
0
0
±10
±5
1.7
4.7
1.8
4.8
–40
–40
±15
±20
1.7
4
1.8
4
INM
). See
µA
µA
µA
µA
V
V
V
V
dB
dB
dB
dB
mV
mV
µV/°C
µV/°C
V
V
V
V
66011f
3
LTC6601-1
DC ELECTRICAL CHARACTERISTICS
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
I
LOAD
(V
OUT
= 0, R
+
+ V
= 100k. The fi lter is confi gured for a gain of 1 unless otherwise noted. VS is defi ned as (V+ – V–). V
BAL
–
OUT
)/2. V
is defi ned as (V
INCM
INP
+ V
= 25°C. V+ = 3V, V– = 0V, V
A
INM
)/2. V
is defi ned as (V
OUTDIFF
Figure 1.
SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITS
V
OUT
Output Voltage, High, Either Output Pin
(Note 11)
Output Voltage, Low, Either Output Pin
(Note 11)
I
SC
Output Short-Circuit Current,
Either Output Pin (Note 12)
V
S
I
S
Supply Voltage Range
Supply Current, BIAS Pin Tied to V
+
Supply Current, BIAS Pin FloatingV
I
SHDN
V
BIASSD
(Note 13)BIAS Input for Half Power OperationVS = 2.7V to 5V
V
BIASLP
BIAS Input for High Performance OperationVS = 2.7V to 5V
V
BIASHP
R
BIAS
BIAS Float VoltageVS = 2.7V to 5V
V
BIAS
t
ON
t
OFF
Supply Current, BIAS Pin Tied to V
BIAS Input Pin Range for ShutdownVS = 2.7V to 5V
BIAS Input ResistanceVS = 2.7V to 5V
Turn-On TimeVS = 3V, V
Turn-Off TimeVS = 3V, V
–
VS = 3V, IL = 0mA BIAS = V
VS = 3V, IL = –5mA BIAS = V
VS = 3V, IL = –20mA BIAS = V
VS = 5V, IL = 0mA BIAS = V
VS = 5V, IL = –5mA BIAS = V
VS = 5V, IL = –20mA BIAS = V
V
= 3V, IL = 0mA, BIAS Pin Floating
S
V
= 3V, IL = –5mA, BIAS Pin Floating
S
V
= 3V, IL = –20mA, BIAS Pin Floating
S
V
= 5V, IL = 0mA, BIAS Pin Floating
S
V
= 5V, IL = –5mA, BIAS Pin Floating
S
V
= 5V, IL = –20mA, BIAS Pin Floating
S
V
= 3V, IL = 0mA BIAS = V
S
VS = 3V, IL = 5mA BIAS = V
VS = 3V, IL = 20mA BIAS = V
VS = 5V, IL = 0mA BIAS = V
VS = 5V, IL = 5mA BIAS = V
VS = 5V, IL = 20mA BIAS = V
V
= 3V, IL = 0mA, BIAS Pin Floating
S
V
= 3V, IL = 5mA, BIAS Pin Floating
S
V
= 3V, IL = 20mA, BIAS Pin Floating
S
V
= 5V, IL = 0mA, BIAS Pin Floating
S
V
= 5V, IL = 5mA, BIAS Pin Floating
S
V
= 5V, IL = 20mA, BIAS Pin Floating
S
VS = 3V
V
= 5V
S
VS = 2.7V
V
= 3V
S
V
= 5V
S
= 2.7V
S
V
= 3V
S
V
= 5V
S
VS = 2.7V
V
= 3V
S
VS = 5V
= 0.25V to 3V400ns
SHDN
= 3V to 0.25V400ns
SHDN
INCM
OUT
+
= V
– V
= mid-supply, BIAS tied to V+ or fl oating,
+
+
+
+
+
+
+
+
+
+
+
+
OCM
OUT
–
). V
is defi ned as (V
INDIFF
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
±45
l
±60
l
2.75.25V
l
l
l
l
l
l
l
l
l
l
V
l
V– + 1.0V– + 1.5V
l
V– + 2.3V
l
100150200kΩ
l
V– + 1.05 V– + 1.12 V– + 1.25V
245
285
415
350
390
550
240
290
470
370
430
650
120
135
195
175
200
270
110
120
170
150
170
225
±65
±90
32.9
33.1
33.9
16.0
16.2
16.9
0.34
0.35
0.55
–
is defi ned as
OUTCM
– V
INP
V– + 0.4V
450
525
750
625
700
1000
450
525
850
675
775
1100
225
250
350
325
360
475
200
225
300
270
300
400
43
43.5
45
25
25.5
26.5
0.9
1
1.6
+
INM
). See
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
V
4
66011f
LTC6601-1
AC ELECTRICAL CHARACTERISTICS
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
fl oating, unless otherwise noted. (See Figure 2 for the AC test confi guration.) VS is defi ned as (V+ – V–). V
–
V
OUT
)/2. V
is defi ned as (V
ICM
INP
+ V
INM
)/2. V
= 25°C. V+ = 3V, V– = 0V, V
A
is defi ned as (V
OUTDIFF
OUT
+
– V
SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITS
GAINFilter Gain, See Figure 2,
BIAS Pin Tied to V
+
,
AC Gain Measurements Relative to 1MHz
PHASEFilter Phase, See Figure 2,
BIAS Pin Tied to V
NOISEWide Band Output Noise, 14.45MHz Cutoff,
BIAS Pin Tied to V
SNRBIAS Pin Tied to V
+
+
+
= ±0.25V, f
ΔV
IN
V
= 600mV
IN
V
= 600mV
IN
V
= 600mV
IN
V
= 600mV
IN
V
= 600mV
IN
V
= 600mV
IN
V
= 600mV
IN
P-P
P-P
P-P
P-P
P-P
P-P
P-P
ΔVIN = ±0.25V, f
V
= 600mV
IN
V
= 600mV
IN
V
= 600mV
IN
V
= 600mV
IN
V
= 600mV
IN
V
= 600mV
IN
V
= 600mV
IN
P-P
P-P
P-P
P-P
P-P
P-P
P-P
BW = 100MHz
BW = 20MHz
BW = 100MHz
= DC (Note 14)
TEST
, f
= 1MHz
TEST
, f
= 2MHz
TEST
, f
= 5MHz
TEST
, f
= 10MHz
TEST
, f
= 14.45MHz
TEST
, f
= 20MHz
TEST
, f
= 50MHz
TEST
= DC
TEST
, f
= 1MHz
TEST
, f
= 2MHz
TEST
, f
= 5MHz
TEST
, f
= 10MHz
TEST
, f
= 14.45MHz
TEST
, f
= 20MHz
TEST
, f
= 50MHz
TEST
BW = 20MHz
DISTORTION V
IN
= 2V
, 10MHz, BIAS Pin Tied to V+ HD2, Single-Ended Input
TCCutoff Frequency Temperature Coeffi cient–120ppm/°C
O
OUT
INCM
–
). V
= V
= mid-supply, V
OCM
is defi ned as (V
INDIFF
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
OUTCM
–0.25
–0.08
–0.01
–0.54
–2.75
–7.14
–23.70
–6.0
–12.0
–30.7
–67.6
–100.1
–127.3
–0.25
–0.08
–0.01
–0.54
–2.90
–7.43
–23.90
–6.0
–12.4
–31.8
–70.2
–103.5
–130.1
is tied to V+ or
BIAS
is defi ned as (V
– V
INP
INM
±0.05
0
0.02
0.11
–0.34
–2.35
–6.24
–21.70
0
–5.4
–10.8
–28.2
–62.6
–94.1
–122.3
–169.3
71
54
80
82.3
–70
–103
–72
–103
±0.05
0
0.02
0.11
–0.34
–2.50
–6.53
–21.90
0
–5.5
–11.2
–29.3
–65.2
–97.5
–125.1
–173.6
78
58
79
81.7
–64
–71
–70
–72
).
0.25
0.12
0.23
–0.14
–1.95
–5.34
–19.70
–4.8
–9.6
–25.7
–57.6
–88.1
–117.3
0.25
0.12
0.23
–0.14
–2.10
–5.63
–19.90
–4.8
–10.0
–26.8
–60.2
–91.5
–120.1
OUT
µV
µV
µV
µV
+
+
dB
dB
dB
dB
dB
dB
dB
dB
Deg
Deg
Deg
Deg
Deg
Deg
Deg
Deg
RMS
RMS
dB
dB
dBc
dBc
dBc
dBc
dB
dB
dB
dB
dB
dB
dB
dB
Deg
Deg
Deg
Deg
Deg
Deg
Deg
Deg
RMS
RMS
dB
dB
dBc
dBc
dBc
dBc
66011f
5
LTC6601-1
ELECTRICAL CHARACTERISTICS
Note 1: Stresses beyond those listed under the Absolute Maximum
Ratings may cause permanent damage to the device. Exposure to any
Absolute Maximum Rating condition for extended periods may affect
device reliability and lifetime.
Note 2: All pins are protected by steering diodes to either supply. If any
pin is driven beyond the part’s supply voltage, the excess input current
(current in excess of what it takes to drive that pin to the supply rail)
should be limited to less than 10mA.
Note 3: A heat sink may be required to keep the junction temperature
below the Absolute Maximum Rating when the output is shorted
indefi nitely. Long-term application of output currents in excess of the
Absolute Maximum Ratings may impair the life of the device.
Note 4: The LTC6601C/LTC6601I are guaranteed functional over the
operating temperature range –40°C to 85°C.
Note 5: The LTC6601C is guaranteed to meet specifi ed performance from
0°C to 70°C. The LTC6601C is designed, characterized, and expected
to meet specifi ed performance from –40°C to 85°C but is not tested or
QA sampled at these temperatures. The LTC6601I is guaranteed to meet
specifi ed performance from –40°C to 85°C.
Note 6: Output referred voltage offset is a function of the low frequency
gain of the LTC6601. To determine output referred voltage offset, or output
voltage offset drift, multiply this specifi cation by the noise gain (1 + GAIN).
See Applications Information for more details.
Note 7: Input bias current is defi ned as the average of the currents
fl owing into the noninverting and inverting inputs of the internal amplifi er
and is calculated from measurements made at the pins of the IC. Input
offset current is defi ned as the difference of the currents fl owing into the
noninverting and inverting inputs of the internal amplifi er and is calculated
from measurements made at the pins of the IC.
Note 8: Input common mode range is tested using the test circuit of
Figure 1 by measuring the differential DC gain with V
with V
Characteristics table, verifying the differential gain has not deviated from
at the input common mode range limits listed in the Electrical
ICM
= mid-supply, and
ICM
the mid-supply common mode input case by more than 1%, and the
common mode offset (V
common mode offset by more than ±10mV.
The voltage range for the output common mode range is tested using the
test circuit of Figure 1 by measuring the differential DC gain with V
mid-supply, and again with a voltage set on the V
Characteristics table limits, checking the differential gain has not deviated
from the mid-supply common mode input case by more than 1%, and that
the common mode offset (V
from the mid-supply case.
Note 9: Input CMRR is defi ned as the ratio of the change in the input
common mode voltage at the amplifi er input to the change in differential
input referred voltage offset. Output CMRR is defi ned as the ratio of the
change in the voltage at the V
referred voltage offset.
Note 10: Power supply rejection (PSRR) is defi ned as the ratio of the
change in supply voltage to the change in differential input referred voltage
offset. Common mode power supply rejection (PSRRCM) is defi ned as the
ratio of the change in supply voltage to the change in the common mode
offset, V
OUTCM/VOCM
Note 11: Output swings are measured as differences between the output
and the respective power supply rail.
Note 12: Extended operation with the output shorted may cause junction
temperatures to exceed the 150°C limit and is not recommended.
Note 13: Floating the BIAS pin will reliably place the part into the halfpower mode. The pin does not have to be driven. Care should be taken,
however, to prevent external leakage currents in or out of this pin from
pulling the pin into an undesired state.
Note 14: The variable contact resistance of the high speed test equipment
limits the accuracy of this test. These parameters only show a typical
value, or conservative minimum and maximum value.
.
) has not deviated from the mid-supply
OCMOS
pin at the Electrical
OCM
) has not deviated by more than ±10mV
OCMOS
pin to the change in differential input
OCM
OCM
=
6
66011f
TYPICAL PERFORMANCE CHARACTERISTICS
LTC6601-1
Low Power Supply Current
vs Temperature and
Supply Voltage
18.0
V
= V
= MID-SUPPLY
OCM
5V
3V
TEMPERATURE (°C)
500100
17.5
17.0
16.5
(mA)
CC
I
16.0
15.5
15.0
–50
INCM
BIAS PIN FLOATING
Supply Current vs Bias Pin
Voltage and Temperature
50
V
= V
INCM
= 3V
V
S
40
30
(mA)
CC
I
20
10
0
0
BIAS PIN VOLTAGE WITH RESPECT TO V– (V)
= MID-SUPPLY
OCM
1.50.52.5
2.7V
66011 G01
–40°C
25°C
125°C
66011 G04
High Performance Supply Current
vs Temperature and
Supply Voltage
35
V
= V
INCM
BIAS PIN TIED TO V
34
33
(mA)
CC
I
32
31
12525–2575
30
–50
= MID-SUPPLY
OCM
+
TEMPERATURE (°C)
500100
5V
3V
2.7V
12525–2575
66011 G02
Shutdown Supply Current
vs Supply Voltage and Temperature
1
125°C
–40°C
0.1
(mA)
CC
I
0.01
V
INCM
0.001
312
0
SUPPLY VOLTAGE (V)
25°C
= V
= MID-SUPPLY
OCM
BIAS PIN TIED TO V
31
–
524
66011 G05
Shutdown Supply Current
vs Temperature and
Supply Voltage
0.8
V
= V
BIAS PIN TIED TO V
0.7
0.6
0.5
0.4
(mA)
CC
I
0.3
0.2
0.1
0
–50
INCM
= MID-SUPPLY
OCM
5V
3V
TEMPERATURE (°C)
–
2.7V
500100
Low Power Mode Supply Current
vs Supply Voltage and Temperature
100
125°C
10
1
(mA)
CC
I
0.1
0.01
0.001
0
–40°C
25°C
V
= V
INCM
SUPPLY VOLTAGE (V)
= MID-SUPPLY
OCM
BIAS PIN FLOATING
31
12525–2575
66011 G03
524
66011 G06
High Performance Supply Current
vs Supply Voltage and Temperature
100
125°C
10
–40°C
25°C
V
= V
INCM
SUPPLY VOLTAGE (V)
= MID-SUPPLY
OCM
BIAS PIN TIED TO V
31
(mA)
CC
I
0.1
0.01
0.001
1
0
+
524
66011 G07
High Performance Mode
Differential VOS vs Temperature
1.00
VS = 3V
= V
V
INCM
0.75
BIAS PIN TIED TO V
5 REPRESENTATIVE UNITS
0.50
0.25
0.00
–0.25
INPUT REFERRED (mV)
OS
–0.50
V
–0.75
–1.00
–50
= MID-SUPPLY
OCM
+
25–25
TEMPERATURE (°C)
66011 G08
1.00
0.75
0.50
0.25
0.00
–0.25
INPUT REFERRED (mV)
OS
–0.50
V
–0.75
12505075100
–1.00
Low Power Mode Differential VOS
vs Temperature
VS = 3V
= V
V
INCM
BIAS PIN FLOATING
5 REPRESENTATIVE UNITS
–50
= MID-SUPPLY
OCM
25–25
TEMPERATURE (°C)
12505075100
66011 G09
66011f
7
LTC6601-1
TYPICAL PERFORMANCE CHARACTERISTICS
High Performance Common Mode
VOS vs Temperature
10
5
(mV)
0
OSCM
V
–5
VS = 3V
= V
V
INCM
BIAS PIN TIED TO V
5 REPRESENTATIVE UNITS
–10
–50
= MID-SUPPLY
OCM
+
25–25
TEMPERATURE (°C)
BIAS Pin Input Resistance
vs Temperature
200
VS = 3V
= V
= MID-SUPPLY
OCM
175
V
INCM
66011 G10
Low Power Common Mode VOS
vs Temperature
15
10
5
(mV)
0
OSCM
V
–5
VS = 3V
–10
V
= V
INCM
BIAS PIN FLOATING
5 REPRESENTATIVE UNITS
–15
12505075100
–50
= MID-SUPPLY
OCM
25–25
TEMPERATURE (°C)
12505075100
66011 G11
BIAS Pin Float Voltage
vs Temperature
1.20
VS = 3V
= V
= MID-SUPPLY
OCM
1.15
V
INCM
Internal Amplifi er Input Bias
Current vs Temperature
–5
LOW POWER MODE
–10
–15
(µA)
BIAS
I
–20
–25
–30
–50
(BIAS PIN FLOATING)
HIGH PERFORMANCE MODE
(BIAS PIN TIED TO V
VS = 3V
= V
V
INCM
= MID-SUPPLY
OCM
TEMPERATURE (°C)
Filter Input Resistance
vs Temperature
1.0050
VS = 3V
= V
= MID-SUPPLY
OCM
= 200 DIFFERENTIAL
= 133.3 SINGLE-ENDED
1.0025
(/)
V
INCM
R
NOMINAL
R
NOMINAL
SEE FIGURE 1 FOR CONFIGURATION
+
)
25–25
12505075100
66011 G12
150
RESISTANCE ()
125
100
–50
Low Frequency Gain
vs Temperature
1.010
VS = 3V
= V
V
INCM
5 REPRESENTATIVE UNITS
1.005
1.000
GAIN (V/V)
0.995
0.990
–50
25–25
TEMPERATURE (°C)
= MID-SUPPLY
OCM
25–25
TEMPERATURE (°C)
66011 G13
66011 G16
1.10
FLOAT VOLTAGE (V)
1.05
1.00
12505075100
–50
25–25
TEMPERATURE (°C)
66011 G14
High Performance Mode
Frequency Response of 12
Possible Filter Confi gurations
10
0
–10
GAIN (dB)
–20
VS = 3V
= V
V
INCM
BIAS PIN TIED TO V
12505075100
–30
0.1101001
= MID-SUPPLY
OCM
+
FREQUENCY (MHz)
66011 G17
NOMINAL
1.0000
0.9975
RESISTANCE/R
SINGLE-ENDED
0.9950
12505075100
–50
25–25
TEMPERATURE (°C)
DIFFERENTIAL
12505075100
66011 G15
Low Power Mode Frequency
Response of 12 Possible Filter
Confi gurations
10
0
–10
GAIN (dB)
–20
VS = 3V
= V
V
INCM
BIAS PIN FLOATING
–30
0.1101001
= MID-SUPPLY
OCM
FREQUENCY (MHz)
66011 G18
8
66011f
TYPICAL PERFORMANCE CHARACTERISTICS
High Performance Mode Gain
and Phase Repeatability of 10
Random Units
0.20
VS = 3V
= V
V
INCM
0.15
BIAS PIN TIED TO V
SEE FIGURE 2
0.10
MAX – AVERAGE
0.05
00
–0.05
MIN – AVERAGE
GAIN DEVIATION (dB)
–0.10
–0.15
–0.20
0.1101001
= MID-SUPPLY
OCM
+
ϕ
– ϕ
MAX
AVERAGE
ϕ
– ϕ
MIN
AVERAGE
FREQUENCY (MHz)
66011 G19
4
3
PHASE DEVIATION (DEG)
2
1
–1
–2
–3
–4
Low Power Mode Gain and Phase
Repeatability of 10 Random Units
0.20
VS = 3V
V
0.15
BIAS PIN FLOATING
SEE FIGURE 1
0.10
0.05
00
–0.05
GAIN DEVIATION (dB)
–0.10
–0.15
–0.20
0.1101001
= V
INCM
MAX – AVERAGE
MIN – AVERAGE
= MID-SUPPLY
OCM
ϕ
MAX
ϕ
MIN
FREQUENCY (MHz)
– ϕ
– ϕ
AVERAGE
AVERAGE
LTC6601-1
4
3
PHASE DEVIATION (DEG)
2
1
–1
–2
–3
–4
66011 G20
High Performance Mode Gain Error
of 10 Random Units Normalized to
1MHz
3
VS = 3V
= V
OCM
= 25°C
+SPECIFICATION
= MID-SUPPLY
–SPECIFICATION
FREQUENCY (MHz)
V
ICM
BIAS PIN TIED TO V+
2
10 RANDOM UNITS PLOTTED
T
A
1
0
–1
GAIN ERROR (dB)
–2
–3
110100
Low Power Mode Phase Error of
10 Random Units
15
VS = 3V
= V
= 25°C
= MID-SUPPLY
OCM
–SPECIFICATION
FREQUENCY (MHz)
+SPECIFICATION
V
ICM
BIAS PIN FLOATING
10
10 RANDOM UNITS PLOTTED
T
A
5
0
–5
PHASE ERROR (DEG)
–10
–15
110100
66011 G21
66011 G24
Low Power Mode Gain Error of
10 Random Units Normalized to
1MHz
3
VS = 3V
= V
V
ICM
BIAS PIN FLOATING
2
10 RANDOM UNITS PLOTTED
T
A
1
0
–1
GAIN ERROR (dB)
–2
–3
110100
= MID-SUPPLY
OCM
= 25°C
+SPECIFICATION
–SPECIFICATION
FREQUENCY (MHz)
Turn On and Turn Off Transient
Response
5
4
3
2
1
(V)
0
OUTDIFF
–1
V
–2
–3
–4
–5
VS = 5V
V
0
OUTDIFF
BIAS PIN
2
TIME (µs)
66011 G22
66011 G25
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
61345
High Performance Mode Phase
Error of 10 Random Units
Normalized 100 Resistor TrimNormalized 125 Resistor Trim
900
800
700
600
500
400
FREQUENCY
300
200
100
0
0.993
NORMALIZED RESISTANCE
AVERAGE = 100Ω
STD. DEV = 0.19Ω
1.0091.0010.997
1.005
66011 G34
1000
AVERAGE = 125Ω
900
STD. DEV = 0.22Ω
800
700
600
500
400
FREQUENCY
300
200
100
0
0.99
NORMALIZED RESISTANCE
1.0061.002
1.010.9980.994
66011 G35
66011f
TYPICAL PERFORMANCE CHARACTERISTICS
LTC6601-1
Normalized 200 Resistor Trim
1000
AVERAGE = 200Ω
900
STD. DEV = 0.37Ω
800
700
600
500
400
FREQUENCY
300
200
100
0
0.99
NORMALIZED RESISTANCE
Normalized 21.1pF Capacitor Trim
1200
AVERAGE = 21.1pF
STD. DEV = 0.07pF
1000
800
600
FREQUENCY
400
200
0
0.984
NORMALIZED CAPACITANCE
Normalized Input 400
Resistor Trim
900
AVERAGE = 400.01Ω
STD. DEV = 1.0Ω
800
700
600
500
400
FREQUENCY
300
200
100
0
1.010.9980.994
1.0061.002
66011 G36
0.99
NORMALIZED RESISTANCE
1.010.9980.994
1.0061.002
66011 G37
Normalized 33.3pF
Capacitor Trim
1000
AVERAGE = 33.3pF
900
STD. DEV = 0.09pF
800
700
600
500
400
FREQUENCY
300
200
100
1.0091.003
1.0150.9970.990
66011 G39
0
0.988
NORMALIZED CAPACITANCE
1.0160.9990.993
1.0101.005
66011 G40
Normalized Feedback 400
Resistor Trim
1000
AVERAGE = 400.01Ω
900
STD. DEV = 0.87Ω
800
700
600
500
400
FREQUENCY
300
200
100
0
0.99
NORMALIZED RESISTANCE
Normalized 48.2pF
Capacitor Trim
1200
AVERAGE = 48.2pF
STD. DEV = 0.08pF
1000
800
600
FREQUENCY
400
200
0
0.9950.992
NORMALIZED CAPACITANCE
1.010.9980.994
1.0061.002
66011 G38
1.0101.0010.998
1.0071.004
66011 G41
Normalized 81.5pF
Capacitor Trim
1000
AVERAGE = 81.5pF
900
STD. DEV = 0.1pF
800
700
600
500
400
FREQUENCY
300
200
100
0
0.9960.993
NORMALIZED CAPACITANCE
1.0071.004
66011 G42
Normalized 10.55pF
Capacitor Trim
400
AVERAGE = 10.55pF
STD. DEV = 0.03pF
350
300
250
200
FREQUENCY
150
100
50
1.0101.0020.999
0
0.9910.987
NORMALIZED CAPACITANCE
1.0091.005
1.0141.0000.996
66011 G43
Normalized 16.1pF
Capacitor Trim
350
AVERAGE = 16.1pF
STD. DEV = 0.05pF
300
250
200
150
FREQUENCY
100
50
0
NORMALIZED CAPACITANCE
0.9950.9920.988
1.0101.006
1.0141.0030.999
66011 G44
66011f
11
LTC6601-1
PIN FUNCTIONS
(Refer to the Block Diagram)
IN1+, IN2+, IN4+ (Pins 2, 1, 20): Input to a trimmed 100Ω,
200Ω, 400Ω resistor which feeds a noninverting summing
–
node. Can accept an input signal, be fl oated or tied to OUT
.
For best performance, stray capacitance should be kept as
low as possible by keeping printed circuit connections as
short and direct as possible. If necessary, strip back the
surrounding ground plane away from these pins.
BIAS (Pin 3): Input to a three-state comparator whose
three states allow the user to tailor amplifi er power. The
pin impedance appears as a 150k resistor whose default
–
open-circuit potential is 1.15V with respect to the V
supply. If BIAS is driven to within 0.4V of the V
power
–
supply, the
amplifi er is placed into a low power shutdown, consuming typically 350µA. When BIAS is fl oated, the amplifi er
operates in its low power active state. Forcing the pin 2.3V
–
above V
places the part into the high performance active
state. See Applications Information for more detail.
–
, IN2–, IN4– (Pins 4, 5, 6): Input to a trimmed 100Ω,
IN1
200Ω, 400Ω resistor which feeds an inverting summing
node. Can accept an input signal, be fl oated or tied to
+
. For best performance, it is highly recommended
OUT
that stray capacitance be kept to as low as possible by
keeping printed circuit connections as short and direct
as possible, and if necessary, stripping back nearby surrounding ground plane away from these pins.
C1, C2 (Pins 7, 8): Input to a trimmed 16.1pF, 33.3pF
capacitor which feeds a noninverting summing node.
–
Typically, either fl oat or tie to OUT
pins is tied to a low impedance source other than OUT
. If either of these
–
,
a resistance of at least 25Ω should be placed in series.
For best performance, it is highly recommended that stray
capacitance be kept to as low as possible by keeping printed
circuit connections as short and direct as possible, and
if necessary, stripping back nearby surrounding ground
plane away from these pins.
C3, C4 (Pins 9, 10): Input to a trimmed 10.55pF, 21.1pF
capacitor which feeds the amplifi er inverting summing
+
node. Typically, either fl oat or tie to OUT
. For best performance, it is highly recommended that stray capacitance
be kept to as low as possible by keeping printed circuit
connections as short and direct as possible, and if necessary, stripping back nearby surrounding ground plane
away from these pins.
the internal feedback network, each pin can drive an additional 50Ω to ground with typical short-circuit current
limiting of ±65mA. Capacitive loading of these pins should
be minimized by resistively decoupling the outputs from
the load with at least 25Ω.
(Pin 12): Output Common Mode Reference Voltage.
V
OCM
The voltage on V
sets the output common mode voltage
OCM
level (which is defi ned as the average of the voltages on
the OUT
and OUT– pins). The V
pin is the midpoint
OCM
+
of an internal resistive voltage divider between the supplies, developing a (default) mid-supply voltage potential
to maximize output signal swing. The V
pin can be
OCM
overdriven by an external voltage reference capable of
driving the input impedance presented by the V
The V
pin has an input resistance of approximately 18k
OCM
OCM
pin.
to a mid-supply potential. It should be bypassed with a
high quality ceramic bypass capacitor (for instance of X7R
dielectric) of at least 0.01F, (unless using symmetrical
split supplies, then connect directly to a low impedance,
low noise ground plane) to minimize common mode noise
from being converted to differential noise by impedance
mismatches both externally and internally to the IC.
12
66011f
LTC6601-1
PIN FUNCTIONS
V+, V– (Pins 14, 13): Power Supply Pins. It is critical that
close attention be paid to supply bypassing. For single
supply applications (Pin 13 grounded), it is recommended
that a high quality 0.1F surface mount ceramic bypass
capacitor (X7R dielectric for instance) be placed between
Pins 14 and 13, with direct short connections. Pin 13
should be tied directly to a low impedance ground plane
with minimal routing. For dual (split) power supplies, it
is recommended that at least two additional high quality
0.1F ceramic capacitors are used to bypass V
–
to ground, again with minimal routing. For driving
and V
large loads (< 200Ω), additional bypass capacitance may
be added for optimal performance. Keep in mind that small
geometry (e.g., 0603) surface mount ceramic capacitors
have a much lower ESL than do leaded capacitors, and
perform best in high speed applications.
C7, C8 (Pins 17, 16): Input to a trimmed 10.55pF, 21.1pF
capacitor which feeds the amplifi er noninverting summing node. Typically, either fl oat or tie to OUT
performance, stray capacitance should be kept as low as
possible by keeping printed circuit connections as short
and direct as possible.If necessary, strip back the surrounding ground plane away from these pins.
(Refer to the Block Diagram)
+
to ground
–
. For best
C5, C6 (Pins 19, 18): Input to a trimmed 16.1pF, 33.3pF
capacitor which feeds an inverting summing node. Typically, either fl oat or tie to OUT
tied to a low impedance source other than OUT
sistance of at least 25Ω should be placed in series. For
best performance, it is highly recommended that stray
capacitance be kept to as low as possible by keeping printed
circuit connections as short and direct as possible, and if
necessary, stripping back nearby surrounding reference
plane away from these pins.
Exposed Pad (Pin 21): Always tie the underlying Exposed
Pad to V
the pad to ground. Tie it to V
–
(Pin 13). If split supplies are used, do not tie
+
. If either of these pins are
–
.
+
, a re-
66011f
13
Loading...
+ 28 hidden pages
You need points to download manuals.
1 point = 1 manual.
You can buy points or you can get point for every manual you upload.