LTC1443IS#TR Linear Technology, LTC1443IS#TR Datasheet - Page 8

• Manufacturer Part Number: LTC1443IS#TR
• Description: IC COMP QUAD LP 1.182VREF 16SOIC
• Manufacturer: Linear Technology
• Type: with Voltage Referencer

Specifications of LTC1443IS#TR

• Number Of Elements: 4
• Output Type: CMOS, TTL
• Voltage - Supply: 2 V ~ 11 V, ±1 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

APPLICATIO S I FOR ATIO
LTC1443/LTC1444/LTC1445
V
It can source up to 200µA and sink up to 15µA with a 5V
supply. The reference can drive a bypass capacitor of up to
0.01µF without oscillation and by inserting a series resistor,
capacitance values up to 100µF can be used (Figure 1).
Figure 2 shows the resistor value required for different
capacitor values to achieve critical damping.
Bypassing the reference can help prevent false tripping of
the comparators by preventing glitches on the V
reference output voltage. Figure 3 shows the bypassed
reference output with a square wave applied to the V
Resistors R1 and R2 set 10mV of hysteresis, while R3
damps the reference response. Note that the comparator
output doesn’t trip.
Hysteresis
Hysteresis can be added to the LTC1444/LTC1445 by
connecting a resistor (R1) between the REF and HYST
pins, and a second resistor (R2) from HYST to V
8
–
. The reference accuracy is 1.5% from – 40°C to 85°C.
Figure 2. Damping Resistance vs Bypass Capacitor Value
Figure 1. Damping the Reference Output
1000
100
0.1
REFERENCE
10
0.001
1
OUTPUT
U
0.01
CAPACITOR VALUE (µF)
U
R1
C1
0.1
V
–
LTC1443/44/45 • F01
REF
LTC144X
W
1
LTC1443/44/45 • F02
10
–
U
(Figure 4).
+
or the
+
pin.
The difference between the upper and lower threshold volt-
ages or hysteresis voltage band (V
voltage difference between the REF and HYST pins. When
more hysteresis is added, the upper threshold increases the
same amount as the lower threshold decreases. The maxi-
mum voltage allowed between REF and HYST is 50mV,
V
+
V
OUT
REF
8V
5V
I
REF
Figure 4. Programmable Hysteresis
5V
TO 8V
Figure 3a. V
Figure 3b. V
R2
2.4M
10k
R1
R1
R2
14
R3
430Ω
8
C1
1.0µF
14
REF
HYST
+
5
4
8
+
Glitching Test Circuit
2ms/DIV
Glitching Response
IN A
IN A
HYST
REF
LTC1445
–
+
LTC1443/44/45 • F04
9
+
–
HB
V
+
3
9
LTC1443/1444/1445 • TA02
LTC1445
) is equal to twice the
LTC1443/44/45 • F03
V
–
R1 =
R2 =
(
(2)(I
1.221V –
2
V
HB
I
REF
OUT
REF
)
V
HB
2
)
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