LT1720 Linear Technology, LT1720 Datasheet - Page 3

• Manufacturer Part Number: LT1720
• Description: 4ns/ 150MHz Dual Comparator with Independent Input/Output Supplies
• Manufacturer: Linear Technology

ELECTRICAL CHARACTERISTICS
SYMBOL
I
I
CMRR
PSRR
A
V
V
I
t
t
t
t
t
t
f
Note 1: Absolute Maximum Ratings are those values beyond which the
life of a device may be impaired.
Note 2: If one input is within these common mode limits, the other
input can go outside the common mode limits and the output will be
valid.
Note 3: The LT1720/LT1721 comparators include internal hysteresis.
The trip points are the input voltage needed to change the output state
in each direction. The offset voltage is defined as the average of V
and V
Note 4: The common mode rejection ratio is measured with V
and is defined as the change in offset voltage measured from V
– 0.1V to V
Note 5: The power supply rejection ratio is measured with V
and is defined as the change in offset voltage measured from V
2.7V to V
Note 6: Because of internal hysteresis, there is no small-signal region
in which to measure gain. Proper operation of internal circuity is
ensured by measuring V
range, otherwise specifications are at T
B
OS
CC
PD20
PD5
SKEW
JITTER
MAX
r
f
V
OH
OL
t
PD
TRIP
CC
–
, while the hysteresis voltage is the difference of these two.
CM
= 6V, divided by 3.3V.
= 3.8V, divided by 3.9V.
PARAMETER
Input Bias Current
Input Offset Current
Common Mode Rejection Ratio
Power Supply Rejection Ratio
Voltage Gain
Output High Voltage
Output Low Voltage
Supply Current (Per Comparator)
Propagation Delay
Propagation Delay
Differential Propagation Delay
Propagation Delay Skew
Output Rise Time
Output Fall Time
Output Timing Jitter
Maximum Toggle Frequency
OH
and V
OL
with only 10mV of overdrive.
A
= 25 C. V
CC
= 5V, V
CM
90% to 10%
CONDITIONS
(Note 4)
(Note 5)
(Note 6)
I
I
V
V
V
V
(Note 9) Between Channels
(Note 10) Between t
10% to 90%
V
V
V
V
SOURCE
SINK
CC
CC
CC
OVERDRIVE
OVERDRIVE
IN
CM
OVERDRIVE
OVERDRIVE
CM
CC
= 1V
The
= 1.2V
= 5V
= 5V
= 3V
= 2V, f = 20MHz
TRIP
=
= 10mA, V
=
CM
= 4mA, V
+
= 1V, C
P-P
denotes specifications that apply over the full operating temperature
= 20mV (Note 7)
= 5mV (Notes 7, 8)
= 50mV, V
= 50mV, V
(6dBm), Z
IN
Note 7: Propagation delay measurements made with 100mV steps.
Overdrive is measured relative to V
Note 8: t
low values of overdrive. The LT1720/LT1721 are 100% tested with a
100mV step and 20mV overdrive. Correlation tests have shown that
t
performed to guarantee that all internal bias conditions are correct.
Note 9: Differential propagation delay is defined as the larger of the
two:
where (MAX) and (MIN) denote the maximum and minimum values of
a given measurement across the different comparator channels.
Note 10: Propagation Delay Skew is defined as:
PD
IN
OUT
= V
t
= V
PD
limits can be guaranteed with this test, if additional DC tests are
SKEW
t
t
TRIP
PDLH
PDHL
CC
CC
+
= 10pF, V
TRIP
/t
IN
PD
= 3V
= 5V
PD
–
= |t
= 50
+
– 10mV
–
= t
= t
cannot be measured in automatic handling equipment with
+ 10mV
PDLH
PDLH(MAX)
PDHL(MAX)
OVERDRIVE
– t
t
t
PDHL
PD
PD
+
–
– t
– t
|
PDLH(MIN)
PDHL(MIN)
= 20mV, unless otherwise specified.
V
CC
MIN
– 6
55
65
TRIP
– 0.4
LT1720/LT1721
.
70.0
62.5
TYP
3.5
4.5
0.3
0.5
2.5
2.2
70
80
15
11
4
7
MAX
0.6
0.4
6.5
8.0
1.0
1.5
10
13
0
7
6
UNITS
ps
ps
3
MHz
MHz
RMS
RMS
mA
mA
dB
dB
ns
ns
ns
ns
ns
ns
ns
ns
A
A
V
V