LT1394 Datasheet, PDF (1/16 Pages) Linear Technology – 7ns, Low Power, Single Supply, Ground-Sensing Comparator

LT1394
7ns, Low Power,
Single Supply, Ground-Sensing
Comparator
FEATURES
DESCRIPTIO
s _UltraFast^TM_{: 7ns}
s _{Low Power: 6mA}
s _{Low Offset Voltage: 0.8mV}
s _{Operates Off Single 5V or Dual ±5V Supplies}
s _{Input Common Mode Extends to Negative Supply}
s _{No Minimum Input Slew Rate Requirement}
s _{Complementary TTL Outputs}
s _{Inputs Can Exceed Supplies without Phase Reversal}
s _{Pin Compatible with LT1016, LT1116 and LT1671}
s _{Output Latch Capability}
s _{Available in 8-Lead MSOP and SO Packages}
U
APPLICATIO S
s _{High Speed A/D Converters}
s _{Zero-Crossing Detectors}
s _{Current Sense for Switching Regulators}
s _{Extended Range V/F Coverters}
s _{Fast Pulse Height/Width Discriminators}
s _{High Speed Triggers}
s _{Line Receivers}
s _{High Speed Sampling Circuits}
, LTC and LT are registered trademarks of Linear Technology Corporation.
UltraFast is a trademark of Linear Technology Corporation.
The LT^®1394 is an UltraFast(7ns) comparator with comple-
mentary outputs and latch. The input common mode range
extends from 1.5V below the positive supply down to the
negative supply rail. Like the LT1016, LT1116 and LT1671,
this comparator has complementary outputs designed to
interface directly to TTL or CMOS logic. The LT1394 may
operate from either a single 5V supply or dual ±5V supplies.
Low offset voltage specifications and high gain allow the
LT1394 to be used in precision applications.
The LT1394 is designed for improved speed and stability for
a wide range of operating conditions. The output stage
provides active drive in both directions for maximum speed
into TTL, CMOS or passive loads with minimal cross-conduc-
tion current. Unlike other fast comparators, the LT1394
remains stable even for slow transitions through the active
region, which eliminates the need to specify a minimum input
slew rate.
The LT1394 has an internal, TTL/CMOS compatible latch for
retaining data at the outputs. The latch holds data as long as
the LATCH pin is held high. Device parameters such as gain,
offset and negative power supply current are not significantly
affected by variations in negative supply voltage.
TYPICAL APPLICATIO
45MHz Single Supply Adaptive Trigger
2k ^5V
2k
5V
10µF ₊
3
6
15
Q1
Q2
5V
2
4
3M
+
A1
LT1227
–
0.005µF
500pF
0.005µF
750Ω
510Ω
36Ω
13
10
3M
14 12
Q3
Q4
15
11
+
0.1µF
100µF
0.1µF
2k
INPUT
5V
+
A2
–^LT1006
470Ω
0.1µF
470Ω
Q1, Q2, Q3, Q4 = CA3096 ARRAY:
TIE SUBSTRATE (PIN 16) TO GROUND
= 1N4148
+
LT1394
–
TRIGGER
OUT
1394 F18
Propagation Delay vs
Input Overdrive
12
T_A = 25°C
10
V_STEP = 100mV
V_S = ±5V
8
t_PDLH
6
t_PDHL
4
2
0
0
10
20
30
40
50
OVERDRIVE (mV)
1394 TA02
1