LINER LTC1444CS Ultralow power quad comparators with reference Datasheet

LTC1443/LTC1444/LTC1445
Ultralow Power Quad
Comparators with Reference
U
FEATURES
■
■
■
■
■
■
■
■
■
■
DESCRIPTIO
Ultralow Quiescent Current: 8.5µA Max
Wide Supply Range
Single: 2V to 11V
Dual: ±1V to ±5.5V
Input Voltage Range Includes the Negative Supply
Reference Output Drives 0.01µF Capacitor
Adjustable Hysteresis (LTC1444/LTC1445)
TTL/CMOS Compatible Outputs
Propagation Delay: 12µs (Typ) (10mV Overdrive)
No Crowbar Current
40mA Continuous Source Current
Pin Compatible Upgrades for MAX924 (LTC1443)
U
APPLICATIO S
■
■
■
■
Battery-Powered System Monitoring
Threshold Detectors
Window Comparators
Oscillator Circuits
®
The LTC 1443/LTC1444/LTC1445 are ultralow power quad
comparators with a built-in reference. The comparators
feature less than 8.5µA supply current over temperature,
an internal reference (1.182V ±1% for LTC1443 or 1.221V
±1% for LTC1444/LTC1445), programmable hysteresis
(LTC1444/LTC1445) and TTL/CMOS output (LTC1443/
LTC1445) that sinks and sources current (open-drain
output for LTC1444). The reference output can drive a
bypass capacitor of up to 0.01µF without oscillation.
The comparators operate from a single 2V to 11V supply
or a dual ±1V to ±5.5V supply (LTC1443). Comparator
hysteresis is easily programmable using two resistors and
the HYST pin (LTC1444/LTC1445). Each comparator’s
input operates from the negative supply to within 1.3V of
the positive supply. The LTC1443/LTC1445 comparator
output stage can continuously source up to 40mA. By
eliminating the cross-conducting current that normally
happens when the comparator changes logic states, power
supply glitches are eliminated.
The LTC1443/LTC1444/LTC1445 are available in the
16-pin SO and PDIP packages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
U
TYPICAL APPLICATIO
Reference Settling Test Circuit
3
VIN
5V
TO 8V
8V
V+
5 IN A+
V+
5V
+
2
–
4 IN A
OUT
2mV/DIV
3.4M
1%
Reference Settling
VREF
–
14 HYST
1.21M
1%
R1
10k
R2
2.4M
8 REF
R3
430Ω
C1
1.0µF
LTC1445
V–
OUT
2ms/DIV
LTC1443/1444/1445 • TA02
9
LTC1443/44/45 • TA01
1
LTC1443/LTC1444/LTC1445
W W
W
AXI U
U
ABSOLUTE
RATI GS
(Note 1)
Voltage:
V + to V –, V + to GND, GND to V – ...........12V to – 0.3V
IN+, IN–, HYST ................. (V + + 0.3V) to (V – – 0.3V)
REF .................................. (V + + 0.3V) to (V – – 0.3V)
OUT (LTC1443) ............. (V + + 0.3V) to (GND – 0.3V)
OUT (LTC1444/LTC1445)
......................................... (V + + 0.3V) to (V – – 0.3V)
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature Range (Soldering, 10 sec)....... 300°C
Current:
IN+, IN–, HYST .................................................. 20mA
REF ................................................................... 20mA
OUT .................................................................. 50mA
OUT Short Circuit Duration (V+ ≤ 5.5V) ....... Continuous
Power Dissipation .............................................. 500mW
Operating Temperature Range
Commercial ............................................ 0°C to 70°C
Industrial ............................................ – 40°C to 85°C
U
U
W
PACKAGE/ORDER I FOR ATIO
TOP VIEW
OUT B 1
16 OUT C
OUT A 2
15 OUT D
V+ 3
14 GND
IN A– 4
IN A+
IN B–
13 IN D+
5
12
6
11 IN C
IN B+ 7
+
LTC1443CN
LTC1443CS
LTC1443IN
LTC1443IS
10 IN C–
REF 8
N PACKAGE
16-LEAD PDIP
IN D–
ORDER PART
NUMBER
9
V–
OUT B 1
16 OUT C
OUT A 2
15 OUT D
V+ 3
14 HYST
IN A– 4
13 IN D+
IN A+
5
12 IN D–
IN B–
6
11 IN C+
IN B+
7
10 IN C–
REF 8
N PACKAGE
16-LEAD PDIP
S PACKAGE
16-LEAD PLASTIC SO
TJMAX = 150°C, θJA = 90°C/ W (N)
TJMAX = 150°C, θJA = 150°C/ W (S)
ORDER PART
NUMBER
TOP VIEW
9
LTC1444CN
LTC1444CS
LTC1444IN
LTC1444IS
LTC1445CN
LTC1445CS
LTC1445IN
LTC1445IS
V–
S PACKAGE
16-LEAD PLASTIC SO
TJMAX = 150°C, θJA = 90°C/ W (N)
TJMAX = 150°C, θJA = 150°C/ W (S)
Consult factory for Military grade parts.
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. V+ = 5V, V – = GND = 0V, unless otherwise noted.
SYMBOL PARAMETER
Power Supply
V+
Supply Voltage Range
ICC
Supply Current
Comparator
VOS
Comparator Input Offset Voltage
IIN
Input Leakage Current (IN+, IN –)
Input Leakage Current (HYST)
VCM
Comparator Input Common Mode Range
CMRR
Common Mode Rejection Ratio
PSRR
Power Supply Rejection Ratio
Noise
Voltage Noise
VHYST
Hysteresis Input Voltage Range
2
CONDITIONS
MIN
●
TYP
MAX
UNITS
11.0
8.5
V
µA
2.0
IN+ = IN – = 80mV
HYST = REF (LTC1444/LTC1445)
●
5.5
VCM = 2.5V
VIN+ = VIN– = 2.5V
LTC1444/LTC1445
●
±3.0
±0.01
±0.02
●
●
●
V – to (V+ – 1.3V)
V+ = 2V to 11V
100Hz to 100kHz
LTC1444, LTC1445
V–
0.1
0.1
20
●
REF – 50mV
±10.0
±1.0
±1.0
V+ – 1.3V
1.0
1.0
REF
mV
nA
nA
V
mV/V
mV/V
µVRMS
V
LTC1443/LTC1444/LTC1445
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. V+ = 5V, V – = GND = 0V, unless otherwise noted.
SYMBOL PARAMETER
Propagation Delay
tPD
VOH
VOL
Output High Voltage
Output Low Voltage
Reference
VREF
Reference Voltage
CONDITIONS
Overdrive = 10mV, COUT = 100pF
Overdrive = 100mV, COUT = 100pF
IO = – 15mA; LTC1443/LTC1445
IO = 1.8mA; LTC1443
IO = 1.8mA; LTC1444/LTC1445
No Load, LTC1443
No Load, LTC1444/
LTC1445
ISOURCE
ISINK
Reference Output Source Current
Reference Output Sink Current
Noise
Voltage Noise
C Temp Range
I Temp Range
C Temp Range
I Temp Range
∆VREF ≤ 1mV
∆VREF ≤ 2.5mV
∆VREF ≤ 5mV
100Hz to 100kHz
MIN
●
TYP
12
4
V+ – 0.4V
●
●
●
●
●
●
●
●
1.170
1.164
1.209
1.203
100
10
10
1.182
1.221
MAX
UNITS
µs
µs
V
GND + 0.4V
V
V– + 0.4V
V
1.194
1.200
1.233
1.239
200
15
15
100
V
V
V
V
µA
µA
µA
µVRMS
The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C.
V+ = 3V, V – = GND = 0V, unless otherwise noted.
SYMBOL PARAMETER
Power Supply
V+
Supply Voltage Range
ICC
Supply Current
Comparator
VOS
Comparator Input Offset Voltage
IIN
Input Leakage Current (IN+, IN–)
Input Leakage Current (HYST)
VCM
Comparator Input Common Mode Range
CMRR
Common Mode Rejection Ratio
PSRR
Power Supply Rejection Ratio
Noise
Voltage Noise
VHYST
Hysteresis Input Voltage Range
tPD
Propagation Delay
VOH
VOL
Output High Voltage
Output Low Voltage
Reference
VREF
Reference Voltage
CONDITIONS
●
Noise
Reference Output Source Current
Reference Output Sink Current
Noise Voltage
TYP
MAX
UNITS
11.0
8
V
µA
2.0
IN+ = IN – = 80mV, HYST = REF
●
5
VCM = 1.5V
VIN+ = VIN– = 1.5V
LTC1444/LTC1445
●
±3.0
±0.01
±0.02
●
●
●
V–
V–
to (V+ –1.3V)
V+ = 2V to 11V
100Hz to 100kHz
LTC1444/LTC1445
Overdrive = 10mV, COUT = 100pF
Overdrive = 100mV, COUT = 100pF
IO = – 10mA, LTC1443/LTC1445
IO = 0.8mA; LTC1443
IO = 0.8mA; LTC1444/LTC1445
No Load, LTC1443
No Load, LTC1444/
LTC1445
ISOURCE
ISINK
MIN
∆VREF ≤ 1mV
∆VREF ≤ 2.5mV
∆VREF ≤ 5mV
100Hz to 100kHz
C Temp Range
I Temp Range
C Temp Range
I Temp Range
0.1
0.1
100
●
REF – 50mV
14
5
●
V+ – 0.4V
●
●
●
●
●
●
●
●
1.170
1.164
1.209
1.203
60
10
10
1.182
1.221
120
15
15
100
±10.0
±1.0
±1.0
+
V – 1.3V
1.0
1.0
mV
nA
nA
V
mV/V
mV/V
µVRMS
REF
V
µs
µs
V
GND + 0.4V
V
V– + 0.4V
V
1.194
1.200
1.233
1.239
V
V
V
V
µA
µA
µA
µVRMS
Note 1: Absolute Maximum Ratings are those values beyond which the life
of the device may be impaired.
3
LTC1443/LTC1444/LTC1445
U W
TYPICAL PERFOR A CE CHARACTERISTICS
LTC1444/LTC1445
Hysteresis Control
Supply Current vs Supply Voltage
Supply Current vs Temperature
5.2
80
5.8
IN+ = (IN– + 100mV)
V – = GND (LTC1443)
TA = 25°C
60
0
–20
–40
SUPPLY CURRENT (µA)
SUPPLY CURRENT (µA)
IN + – IN – (mV)
20
4.8
4.6
4.4
4.2
–60
–80
5.4
5.0
40
20
30
VREF – VHYST (mV)
40
1.0
50
1.5
2.0
2.5
SUPPLY VOLTAGE (V)
LTC1444/LTC1445 Reference
Voltage vs Temperature
1.212
LTC1443 Reference Output
Voltage vs Output Load Current
1.182
1.180
1.178
1.176
1.174
1.170
–60 –40 –20
1.178
2.5
4.0
3.0
V+ = 3V
2.0
V+ = 2V
1.182
1.180
TA = 25°C
V+ = 5V
OUTPUT VOLTAGE HIGH (V)
OUTPUT VOLTAGE HIGH (V)
REFERENCE OUTPUT VOLTAGE (V)
SINK
1.184
1.0
10
15 20 25 30 35
LOAD CURRENT (µA)
40
45
LTC1443/44/45 • TPC07
4
Comparator Output Voltage Low
vs Load Current
TA = 25°C
1.188
5
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
LOAD CURRENT (mA)
LTC1443/44/45 • TPC06
5.0
1.190
0
1.180
Comparator Output Voltage High
vs Load Current
V + = 5V
V – = GND
TA = 25°C
SOURCE
LTC1443/44/45 • TPC05
LTC1443 Reference Output
Voltage vs Output Load Current
1.186
1.181
0 20 40 60 80 100 120 140
TEMPERATURE (°C)
LTC1443/44/45 • TPC04
1.192
1.182
1.179
1.172
0 20 40 60 80 100 120
TEMPERATURE (°C)
V + = 5V
V – = GND
TA = 25°C
1.183
REFERENCE VOLTAGE (V)
REFERENCE VOLTAGE (V)
REFERENCE VOLTAGE (V)
1.216
0 20 40 60 80 100 120
TEMPERATURE (°C)
LTC1443/44/45 • TPC03
V+ = 5V
V – = GND
1.184
1.194
3.0
–60 –40 –20
3.0
1.184
1.186
V+ = 5V
1.208
–60 –40 –20
3.8
LTC1443 Reference Voltage
vs Temperature
1.220
V+ = 3V
V – = 0V
4.2
LTC1443/44/45 • TPC02
LTC1443/44/45 • TPC01
1.224
V+ = 5V
V – = –5V
4.6
3.4
4.0
10
0
V+ = 5V
V – = 0V
5.0
0
10
20
30
40
LOAD CURRENT (mA)
50
60
LTC1443/44/45 • TPC08
2.0
1.5
V + = 2V
V + = 3V
V + = 5V
1.0
0.5
0
0
10
50 60
20 30 40
LOAD CURRENT (mA)
70
80
LTC1443/44/45 • TPC09
LTC1443/LTC1444/LTC1445
U W
TYPICAL PERFOR A CE CHARACTERISTICS
Comparator Response Time vs
Input Overdrives
Comparator Response Time vs
Input Overdrive
20mV
2
1
INPUT VOLTAGE (mV)
0
0
100
0
2
4
6
RESPONSE TIME (µs)
8
10
4
50mV
160
20mV
3
10mV
2
TA = 25°C
180
100mV
1
0
100
140
OUT CONNECTED TO V +
120
100
80
60
40
0
20
–1
LTC1443/44/45 • TPC10
0
2
0
4 6 8 10 12 14 16 18
RESPONSE TIME (µs)
0
1
2
3 4 5 6 7 8
SUPPLY VOLTAGE (V)
9
10
LTC1443/44/45 • TPC12
LTC1443/44/45 • TPC11
Comparator Short-Circuit Source
Current vs Supply Voltage
Comparator Response Time vs
Load Capacitance
12
160
140
10
SOURCE CURRENT (mA)
–1
200
TA = 25°C
SINK CURRENT (mA)
50mV
5
120
RESPONSE TIME (µs)
3
10mV
OUT CONNECTED TO
V – = GND = 0V
100
80
60
40
t PHL
8
t PLH
6
4
20
0
2
0
1
2
3
SUPPLY VOLTAGE (V)
4
0
5
20
60
80
40
LOAD CAPACITANCE (nF)
Supply Current vs
Comparator Input Frequency
Comparator Response Time at
Low Supply Voltage
10000
10000
1000
1000
100
100
LTC1443/44/45 • TPC14
LTC1443/44/45 • TPC13
RESPONSE TIME (µs)
4
100mV
OUTPUT VOLTAGE (V)
TA = 25°C
SUPPLY CURRENT (µA)
INPUT VOLTAGE (mV)
OUTPUT VOLTAGE (V)
5
Comparator Short-Circuit Sink
Current vs Supply Voltage
COUT = 55pF
COUT = 15pF
10
20mV OVERDRIVE
100
10
100mV OVERDRIVE
COUT = 5pF
1
1
1
10
100
1k
10k
INPUT FREQUENCY (Hz)
100k
LTC1329 • TPC15
1
1.1
1.2
1.3
1.4
1.5
1.6
SUPPLY VOLTAGE (V)
LTC1443/44/45 • TPC16
5
LTC1443/LTC1444/LTC1445
U
U
U
PI FU CTIO S
LTC1443
LTC1444/LTC1445
1
OUT B
OUT C
16
1
OUT B
OUT C
16
2
OUT A
OUT D
15
2
OUT A
OUT D
15
3
V+
14
3
V+
4
IN A–
IN D+
13
4
IN A–
IN D+
13
5
IN A+
IN D–
12
5
IN A+
IN D–
12
6
IN B –
IN C+
11
6
IN B –
IN C+
11
7
IN B+
IN C–
10
7
IN B+
IN C–
10
8
REF
9
8
REF
GND
–
–
+
–
+
–
–
+
+
–
1.182V
+
–
+
–
14
+
+
1.221V
V–
1443/44/45 • PD01
OUT B (Pin 1): Comparator B Output. (Open-drain output
for LTC1444). Output can source up to 40mA (LTC1443,
LTC1445) and sink 5mA.
OUT A (Pin 2): Comparator A Output. (Open-drain output
for LTC1444). Output can source up to 40mA (LTC1443,
LTC1445) and sink 5mA.
V+ (Pin 3): Positive Supply.
IN A – (Pin 4): Inverting Input of Comparator A. Input
common mode range from V – to V + – 1.3V. Input current
typically 10pA at 25°C.
IN A + (Pin 5): Noninverting Input of Comparator A. Input
common mode range from V – to V + – 1.3V. Input current
typically 10pA at 25°C.
IN B – (Pin 6): Inverting Input of Comparator B. Input
common mode range from V – to V + – 1.3V. Input current
typically 10pA at 25°C.
IN B + (Pin 7): Noninverting Input of Comparator B. Input
common mode range from V – to V + – 1.3V. Input current
typically 10pA at 25°C.
REF (Pin 8): Reference Output. With respect to V –. Can
source up to 200µA and sink 15µA at 25°C. Drive 0.01µF
bypass capacitor without oscillation.
6
HYST
V–
9
1443/44/45 • PD02
V – (Pin 9): Negative Supply. Connect to ground for single
supply operation on LTC1443.
IN C – (Pin10): Inverting Input of Comparator C. Input
common mode range from V – to V + – 1.3V. Input current
typically 10pA at 25°C.
IN C + (Pin 11): Noninverting Input of Comparator C. Input
common mode range from V – to V + – 1.3V. Input current
typically 10pA at 25°C.
IN D – (Pin 12): Inverting Input of Comparator D. Input
common mode range from V – to V + – 1.3V. Input current
typically 10pA at 25°C.
IN D + (Pin 13): Noninverting Input of Comparator D. Input
common mode range from V – to V + – 1.3V. Input current
typically 10pA at 25°C.
GND (Pin 14): LTC1443 Ground. Connect to V – for single
supply operation.
HYST (Pin 14): LTC1444/LTC1445 Hysteresis Input. Connect to REF if not used. Input voltage range is from VREF
to VREF – 50mV.
LTC1443/LTC1444/LTC1445
U
U
U
PI FU CTIO S
OUT D (Pin 15): Comparator D Output. (Open-drain
output for LTC1444). Output can source up to 40mA
(LTC1443, LTC1445) and sink 5mA.
OUT C (Pin 16): Comparator C Output. (Open-drain output
for LTC1444). Output can source up to 40mA (LTC1443,
LTC1445) and sink 5mA.
U
W
U U
APPLICATIO S I FOR ATIO
The LTC1443/LTC1444/LTC1445 is a family of quad
micropower comparators with a built-in reference (1.182V
for the LTC1443 and 1.221V for the LTC1444/LTC1445).
Features include programmable hysteresis (LTC1444/
LTC1445), wide supply voltage range (2V to 11V) and the
ability of the reference to drive up to a 0.01µF capacitor
without oscillation. The comparator CMOS outputs
(LTC1443/LTC1445) can source up to 40mA while the
LTC1444 has an open-drain output to V –. The supply
current glitches that normally occur when the comparator
output switches states have been eliminated.
tions which helps minimize parasitic feedback through the
supply pins.
Voltage Reference
The internal bandgap reference has a voltage of 1.182V for
LTC1443 or 1.221V for LTC1444/LTC1445 referenced to
V –. The reference accuracy is 1.5% from – 40°C to 85°C.
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).
Power Supplies
Comparator Inputs
The comparator inputs can swing from the negative supply (V –) to within 1.3V maximum of the positive supply
(V +). The inputs can be forced 300mV below V – or above
V + without damage, and the typical input leakage current
is only ±10pA.
Comparator Outputs
The LTC1443 comparator output swings between GND
and V + to assure TTL compatibility with a split supply. The
LTC1444 and LTC1445 outputs swing between V – and V +.
The outputs are capable of sourcing up to 40mA (LTC1443/
LTC1445) and sinking up to 5mA while still maintaining
microampere quiescent currents. The output stage does
not generate crowbar switching currents during transi-
REF
R1
C1
LTC144X
V–
LTC1443/44/45 • F01
Figure 1. Damping the Reference Output
Figure 2 shows the resistor value required for different
capacitor values to achieve critical damping.
1000
RESISTOR VALUE (kΩ)
The comparator family operates from a single 2V to 11V
supply. The LTC1443 includes a separate ground for the
comparator output stage, allowing a split supply ranging
from ±1V to ±5.5V. Connecting V – to GND on the LTC1443
allows single supply operation. If the comparator output
is required to source more than 1mA or the supply source
impedance is high, V + should be bypassed with a 0.1µF
capacitor.
REFERENCE
OUTPUT
100
10
1
0.1
0.001
0.01
0.1
1
CAPACITOR VALUE (µF)
10
LTC1443/44/45 • F02
Figure 2. Damping Resistance vs Bypass Capacitor Value
7
LTC1443/LTC1444/LTC1445
U
W
U U
APPLICATIO S I FOR ATIO
Bypassing the reference can help prevent false tripping of
the comparators by preventing glitches on the V + or the
reference output voltage. Figure 3 shows the bypassed
reference output with a square wave applied to the V + pin.
Resistors R1 and R2 set 10mV of hysteresis, while R3
damps the reference response. Note that the comparator
output doesn’t trip.
The difference between the upper and lower threshold voltages or hysteresis voltage band (VHB) is equal to twice the
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 maximum voltage allowed between REF and HYST is 50mV,
producing a maximum hysteresis voltage band of 100mV. If
hysteresis is not wanted, the HYST pin should be shorted to
REF. Acceptable values for IREF range from 0.1µA to 5µA. If
2.4M is chosen for R2, then R1(kΩ) = VHB (mV).
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 – (Figure 4).
3
5V
TO 8V
V+
5 IN A+
+
2
4 IN A–
OUT
8V
–
V+
5V
8
R2
2.4M
R3
430Ω
REF
2mV/DIV
14 HYST
R1
10k
LTC1445
VREF
V–
9
C1
1.0µF
OUT
LTC1443/44/45 • F03
2ms/DIV
LTC1443/1444/1445 • TA02
Figure 3a. V +
Figure 3b. V +
Glitching Test Circuit
8
IREF
R1 =
REF
R1
LTC1445
VHB
(2)(IREF)
(
1.221V –
14 HYST
R2 =
R2
IREF
9
LTC1443/44/45 • F04
Figure 4. Programmable Hysteresis
8
VHB
2
)
Glitching Response
LTC1443/LTC1444/LTC1445
U
W
U U
APPLICATIO S I FOR ATIO
5V
3
V2
V
R6
1.82M
1%
7 IN B+
+
R8
2M
1%
+
OUT B 1
–
6 IN B
V1
R2
3.40M
1%
–
1/2LTC1444
5 IN A+
+
OUT A 2
R7
1.21M
1%
–
4 IN A
–
14 HYST
R1
1.21M
1%
R3
15k, 1%
R4
2.4M
1%
8
R5
430Ω
5%
C1
1.0µF
REF
V–
9
LTC1443/44/45 • F05
Figure 5. Glitch-Free Level Detector with Hysteresis
Level Detector
The LTC1444 is ideal for use as a multisupply micropower
level detector as shown in Figure 5.
R1 and R2 form a voltage divider from V1 to the noninverting
comparator A input. R6 and R7 are used to divide down V2,
while R8 is the output pull-up resistor for the comparator
outputs. R3 and R4 set the hysteresis voltage and R5 and C1
bypass the reference output. The following design procedure
can be used to select the component values:
1. Choose the V1 voltage trip level, in this example 4.65V.
2. Calculate the required resistive divider ratio.
Ratio = VREF/VIN
Ratio = 1.221V/4.65V = 0.263
3. Choose the required hysteresis voltage band at the input,
VHBIN, in this example 60mV. Calculate the hysteresis
voltage band referred to the comparator input VHB.
VHB = (VHBIN)(Ratio)
4. Choose the values for R3 and R4 to set the hysteresis.
R4 = 2.4M
R3(kΩ) = VHB = 15k
5. Choose the values for R1 and R2 to set the trip point.
R1 = VREF/IBIAS = 1.221V/1µA ≈ 1.21M




VIN
R2 = (R1)
− 1
V
 VREF + HB 
2






4.65V
R2 = (1.21M) 
− 1
15mV
 1.221V +

2


R2 = 3.40M
VHB = (60mV)(0.263)
VHB = 15.78mV
Using the same equations, R6 and R7 are 1.82M and 1.21M
respectfully to set the trip level at 3V for V2.
9
LTC1443/LTC1444/LTC1445
U
PACKAGE DESCRIPTIO
Dimensions in inches (millimeters) unless otherwise noted.
N Package
16-Lead PDIP (Narrow 0.300)
(LTC DWG # 05-08-1510)
0.770*
(19.558)
MAX
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
0.255 ± 0.015*
(6.477 ± 0.381)
0.130 ± 0.005
(3.302 ± 0.127)
0.300 – 0.325
(7.620 – 8.255)
0.009 – 0.015
(0.229 – 0.381)
(
+0.035
0.325 –0.015
8.255
+0.889
–0.381
)
0.045 – 0.065
(1.143 – 1.651)
0.020
(0.508)
MIN
0.065
(1.651)
TYP
0.125
(3.175)
MIN
0.100
(2.54)
BSC
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)
10
0.018 ± 0.003
(0.457 ± 0.076)
N16 1098
LTC1443/LTC1444/LTC1445
U
PACKAGE DESCRIPTIO
Dimensions in inches (millimeters) unless otherwise noted.
S Package
16-Lead Plastic Small Outline (Narrow 0.150)
(LTC DWG # 05-08-1610)
0.386 – 0.394*
(9.804 – 10.008)
16
15
14
13
12
11
10
9
0.150 – 0.157**
(3.810 – 3.988)
0.228 – 0.244
(5.791 – 6.197)
1
0.010 – 0.020
× 45°
(0.254 – 0.508)
2
3
4
5
6
0.053 – 0.069
(1.346 – 1.752)
0.008 – 0.010
(0.203 – 0.254)
0.014 – 0.019
(0.355 – 0.483)
TYP
8
0.004 – 0.010
(0.101 – 0.254)
0° – 8° TYP
0.016 – 0.050
(0.406 – 1.270)
7
0.050
(1.270)
BSC
S16 1098
*DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
**DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
11
LTC1443/LTC1444/LTC1445
U
TYPICAL APPLICATIO
Single Cell to 5V Supply
R1
1.1M
5%
5
R2
82.5k
1%
1 CELL
LITHIUMION
BATTERY
+
6
+
–
R7
51k
5%
–
7
SW
C2
100µF
3
1
14
NC
NC
R5
51k
5%
R4
2.4M
5%
6
VIN
2
B
1/4 LTC1444
7 + HYST
R3
1M
1%
D1
1N5817
+
V
A
1/4 LTC1444
4
L1
10µH
SUMIDA
CD54-100
3
5
2
SENSE
4
1
SHDN
3
LT1300
ILIM
+
SEL
PWR GND
GND
8
C3
100µF
1
8 REF
R6
430Ω
5%
C1
1µF
2, 4
Q1
MMFT2955ETI
LTC1444
REF
9 V–
R9
267k
1%
R8
732k
1% 11
R10
3.37M
5%
+
C
1/4 LTC1444
10
16
13
+
D
1/4 LTC1444
–
12
R11
51k
5%
VCC
R12
51k
15 5%
NMI
µP
RESET
–
C4
0.22µF
LTC1443/44/45 • F06
C2, C3: AUX TPSD107M010R0100 OR
SANYO OS-CON 16SA100M
RELATED PARTS
PART NUMBER
®
LT 1034
DESCRIPTION
COMMENTS
Micropower Dual Reference
1.2V or 2.5V with 7V Auxiliary Reference
LT1179
Quad Micropower Single Supply Precision Op Amp
17µA Max per Amplifier
LTC1285/LTC1288
3V Micropower Sampling 12-Bit ADCs
SO-8 Package, Auto Shutdown to 1nA
LT1389
Nanopower Precision Shunt Reference
800nA Operating Current, 0.05% Accuracy
LTC1440/LTC1441/LTC1442
Ultralow Power Single/Dual Comparator with Reference
2.8µA Typical Quiescent Current
LT1495
Dual Precision Rail-to-Rail Input and Output Op Amp
1.5µA Max per Amplifier
LT1521
300mA Low Dropout Regulator
12µA Quiescent Current
LT1634
Micropower Precision Shunt Reference
10µA Operating Current, 0.05% Accuracy
12
Linear Technology Corporation
144345fa LT/TP 0100 2K REV A • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408)432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com
 LINEAR TECHNOLOGY CORPORATION 1995
Similar pages