LINER LTC1998I

LTC1998
2.5µA, 1% Accurate
SOT-23 Comparator and Voltage
Reference for Battery Monitoring
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FEATURES
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DESCRIPTIO
High Accuracy Trip Voltage: 1% Max Error Using
External 1% Resistors
Adjustable Threshold Voltage and Hysteresis
Quiescent Current: 2.5µA Typ
Output Swings Rail-to-Rail
Thresholds Programmable from 2.5V to 3.25V
Output State Guaranteed for VBATT ≥ 1.5V
Low Profile (1mm) ThinSOTTM Package
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APPLICATIO S
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Lithium-Ion Battery-Powered Equipment
PDAs
Cell Phones
Handheld Instruments
Battery Packs
Pagers
Palm Top Computers
POS Terminals
, LTC and LT are registered trademarks of Linear Technology Corporation.
ThinSOT is a trademark of Linear Technology Corporation.
The LTC®1998 is a micropower comparator and a precision adjustable reference in a 6-pin SOT-23 package that
is optimized for lithium-ion low battery detection circuits.
The LTC1998 features a voltage detection circuit with an
adjustable threshold voltage and hysteresis. The threshold voltage can be programmed from 2.5V to 3.25V with
two external resistors. A 10mV to 750mV hysteresis can
be added with a third external resistor.
A proprietary internal architecture maintains 1% threshold voltage accuracy over temperature with low cost 1%
external resistors.
A separate power supply pin, VLOGIC, allows the batterylow logic output to operate below the battery voltage,
allowing compatibility with low voltage microprocessors
without a pull-up resistor. Power supply glitches are
eliminated by preventing the cross-conducting current
which occurs when the output changes state.
The LTC1998 operates with battery or supply voltages up
to 5.5V and its battery-low output is valid for battery
voltages above 1.5V.
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BLOCK DIAGRA
Threshold Voltage Error vs Temperature
1.0
BATT
0.9
0.7
THRESHOLD
ADJUST
R
BATTLO
VTH.A
% ERROR
1.1R
VHYST.A
VTH.A SET BY 1%
EXTERNAL R,
THRESHOLD = 3V
0.8
VLOGIC
0.6
0.5
0.4
VTH.A = 1V
THRESHOLD = 3V
0.3
1.2V
0.2
VTH.A SHORTED
TO GROUND,
THRESHOLD = 2.5V
0.1
1998 BD
0
–45 –25
35
15
55
–5
TEMPERATURE (°C)
75
95
1998 G05
1998f
1
LTC1998
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ABSOLUTE
AXI U RATI GS
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PACKAGE/ORDER I FOR ATIO
(Note 1)
Total Supply Voltage (BATT or V LOGIC to GND) ......... 6V
Voltage
VTH.A, VH.A ........................... BATT + 0.3V to GND – 0.3V
BATTLO ........................ VLOGIC + 0.3V to GND – 0.3V
Operating Temperature Range (Note 3) ...–40°C to 85°C
Specified Temperature Range (Note 4)
LTC1998C ...........................................–40°C to 85°C
LTC1998I .............................................–40°C to 85°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
TOP VIEW
BATT 1
6 BATTLO
GND 2
5 VLOGIC
VTH.A 3
4 VH.A
ORDER PART
NUMBER
LTC1998CS6
LTC1998IS6
S6 PART MARKING*
LTTY
S6 PACKAGE
6-LEAD PLASTIC SOT-23
TJMAX = 150°C, θJA = 250°C/W
*The temperature grades are indentified by a label on the shipping container.
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. V GND = 0V, unless otherwise noted.
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Power Supply
Supply Voltage Range-BATT
Supply Voltage Range-VLOGIC
●
1.5
●
1
5.5
V
VBATT
V
2.5
3.5
4.2
4.5
µA
µA
µA
3
4.3
5.2
5.5
µA
µA
µA
●
0.6
0.8
0.85
1
%
%
Supply Current, VBATT = 3V,
VTH.A = 1.5V
TA = 25°C
LTC1998CS6
LTC1998IS6
●
●
Supply Current, VBATT = 5.5V,
VTH.A = 1.5V
TA = 25°C
LTC1998CS6
LTC1998IS6
●
●
Monitor
Threshold Accuracy
Hysteresis Accuracy
VBATT.Th = 2.5V, Pin 3 Shorted to Ground
VBATT.Th = 3V, Pin 3 Driven by Precision
Voltage Source to 1V
LTC1998C
LTC1998I
●
●
0.5
0.6
0.61
0.71
%
%
VBATT.Th = 3V, VTH.A = 1V (Note 5)
Programmed with 1% Max External Resistors
LTC1998C
LTC1998I
●
●
0.8
0.9
1
1.1
%
%
VBATT.Th = 3.25V, Pin 3 Diven by Precision
Voltage Source to 1.5V
LTC1998C
LTC1998I
●
●
0.6
0.7
0.65
0.85
%
%
VBATT.Th = 3.25V, VTH.A = 1.5V (Note 5)
Programmed with1% Max External Resistors
LTC1998C
LTC1998I
●
●
0.9
1
1.1
1.3
%
%
5
mV
mV
750
mV
VHYST ≤ 250mV
250mV ≤ VHYST ≤ 750mV
Allowable Hysteresis Range (Note 2)
●
●
–5
●
10
±5
µs
µs
Propagation Delay
COUT = 100pF, Overdrive = 10mV
Overdrive = 100mV
350
150
Threshold Adjust Pin Leakage, ITH.A
VTH.A ≤ 1.5V
●
0.01
1
nA
Hysteresis Adjust Pin Leakage, IH.A
VH.A ≤ 1.5V
●
0.01
1
nA
BATTLO High Voltage
IOUT = –1mA
●
BATTLO Low Voltage
IOUT = 1mA, VBATT ≥ 2V
●
BATTLO Low Voltage
IOUT = 0.25mA, VBATT = 1V
●
Output
VLOGIC – 0.3
V
0.2
0.3
V
V
1998f
2
LTC1998
ELECTRICAL CHARACTERISTICS
Note 4: The LTC1998C is guaranteed to meet specified performance from
0°C to 70°C. The LTC1998C is designed, characterized and expected to
meet specified performance from –40°C to 85°C but is not tested or QA
sampled at these temperatures. The LTC1998I is guaranteed to meet
specified performance from –40°C to 85°C.
Note 5: This parameter is not 100% tested.
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: Maximum allowable hysteresis depends on desired trip voltages.
See application notes for details.
Note 3: LTC1998C and LTC1998I are guaranteed functional over the
operating temperature range of – 40°C to 85°C.
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TYPICAL PERFOR A CE CHARACTERISTICS
Quiescent Supply Current vs
Supply Voltage
3.0
3.5
TA = 25°C
VLOGIC = VBATT
3.0
SUPPLY CURRENT (µA)
SUPPLY CURRENT (µA)
VTH.A = 1.5V
2.5
3.5
VBATT = VLOGIC = 3V
VTH.A = 0V
2.0
1.5
1.0
THRESHOLD VOLTAGE (V)
3.5
Threshold Voltage vs Threshold
Adjust Voltage
Quiescent Supply Current vs
Temperature
2.5
VTH.A = 1.5V
2.0
1.5
1.0
3.0
0.5
0.5
0
–50
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
SUPPLY VOLTAGE (V)
2.5
–30
–10
10
30
50
TEMPERATURE (°C)
70
90
0
1998 G03
1998 G02
1998 G01
Available Hysteresis vs
Threshold Voltage
Threshold Voltage Error vs
Temperature
Input Current vs Temperature
1.0
750
10000
0.7
250
0.6
0.5
0.4
VTH.A = 1V
THRESHOLD = 3V
0.3
0.2
VTH.A SHORTED
TO GROUND,
THRESHOLD = 2.5V
INPUT CURRENT VTH.A, VH.A (pA)
VTH.A SET BY 1%
EXTERNAL R,
THRESHOLD = 3V
0.8
% ERROR
AVAILABLE HYSTERESIS (mV)
0.9
500
1.5
0.5
1.0
THRESHOLD ADJUST VOLTAGE (V)
VIN = 1.5V
1000
VIN = 1V
100
VIN = 0.5V
10
1
0.1
0
2.5
3.25
2.75
3.0
LOW BATTERY THRESHOLD VOLTAGE (V)
1998 G04
0
–45 –25
35
15
55
–5
TEMPERATURE (°C)
75
95
1998 G05
0.1
35 45
55
65 75 85 95 105 115 125
TEMPERATURE (°C)
1998 G06
1998f
3
LTC1998
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TYPICAL PERFOR A CE CHARACTERISTICS
Output Low Voltage vs Load
Current
Output High Voltage vs Load
Current
OUTPUT VOLTAGE (V)
TA = 25°C
VLOGIC = VBATT = 3V
TA = 85°C
0.4
TA = 25°C
0.2
TA = –40°C
120
0
TA = 85°C
TA = 25°C
TA = –40°C
–50
–100
TA = –40°C
TA = 25°C
–150
TA = 85°C
–200
TA = 25°C
VLOGIC = VBATT
–250
0
1
2
3
4
OUTPUT SINK CURRENT (mA)
5
100
CURRENT (mA)
OUTPUT VOLTAGE RELATIVE TO VBATT (mV)
0.6
Output Short-Circuit Current vs
Supply Voltage
1
2
3
4
OUTPUT SOURCE CURRENT (mA)
1998 G07
80
60
5
1998 G08
SOURCE CURRENT,
BATTLO SHORTED TO GND
40
20
BATT = 3V
BATT = 5V
TA = 25°C
VBATT = VLOGIC
SINK CURRENT,
BATTLO SHORTED
TO VLOGIC
0
1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
SUPPLY VOLTAGE (V)
1998 G09
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PI FU CTIO S
BATT (Pin 1): Battery Voltage to be monitored. Supply
current is also drawn from this pin. Board layout should
connect this pin to the battery(+) terminal, through a trace
that does not conduct load current.
GND (Pin 2): Ground should be connected to the battery
(–) terminal through a trace that does not conduct load
return current.
VTH.A (Pin 3): Threshold Adjust Pin. Adjusts the low
battery threshold voltage, VBATT.Th = 2.5V + (VTH.A/2).
VTH.A can be supplied by a voltage source or a resistor
divider.
VH.A (Pin 4): Hysteresis Adjust. Hysteresis threshold
voltage VTH2 = 2.5V + (VH.A/2). VH.A can be supplied by a
voltage source or resistor divider. VH.A must always be
programmed to a higher potential than VTH.A. Hysteresis
voltage, VHYST = VTH2 – VBATT.Th.
VLOGIC (Pin 5): Positive Supply Voltage for Output Driver.
This voltage can be driven from an external logic supply or
tied to BATT.
BATTLO (Pin 6): Output of Comparator. Low for BATT <
VBATT.Th (low battery threshold voltage). Output state
guaranteed for VBATT ≥ 1.5V.
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QUICK DESIG GUIDE
How to Calculate the External Resistor Values
The LTC1998 is a low battery warning indicator and is
especially designed for monitoring the voltage of singlecell Lithium-Ion batteries. The LTC1998 compares its
supply pin (BATT) to an accurate internal reference; if the
battery voltage falls below the programmed low battery
threshold voltage of the LTC1998, the battery low pin
(BATTLO) will change state, from high to low, to indicate
a low battery condition. The low battery threshold voltage
is programmed via the voltage threshold adjust pin (VTH.A).
A hysteresis adjust pin (VH.A) will add hysteresis to the
programmed value of the low battery threshold voltage.
1998f
4
LTC1998
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QUICK DESIG GUIDE
Typical Application
Table 1: Design Equations for R1, R2, R3, Figure 1
Choose desired values for:
• VBATT.Th: Low Battery Threshold Voltage
• VHYST: Hysteresis Voltage
• IR: Max Allowable Resistor Current
Solve:
Example 1: A system using a 4.2V (fully charged) LithiumIon battery requires a low battery threshold of 2.7V,
100mV hysteresis and can allow up to 4.2µA maximum
resistor current.
RTOTAL = 1MΩ, R1 = 786k, R2 = 66k and R3 = 148k
Choose standard 1% values.
R1 = 787k, R2 = 66.5k, R3 = 147k
1.5V TO 4.2V
RTOTAL = R1 + R2 + R3 =
4.2V
IR
+
Li-Ion


5V
R1 = RTOTAL • 
– 1
 VBATT .Th + VHYST 
VLOGIC
0.1µF
R1
1%
4
R2
1%
1
BATT
5
VH.A VLOGIC
µP
LTC1998
3
R3
1%

 5V
R2 = RTOTAL • 
– 1 – R1
 VBATT .Th 
R3 = RTOTAL – R1 – R2
REGULATOR
6
VTH.A BATTLO
GND
2
1998 F01
Figure 1. Low Battery Threshold Detector with Hysteresis
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APPLICATIO S I FOR ATIO
Low Battery Threshold Voltage Adjustment, Pin 3
The low battery threshold voltage is the battery voltage
which will trip the (BATTLO) pin high to low. It should be
adjusted via the threshold adjust pin (VTH.A). This is a high
input impedance pin that senses an externally applied
voltage and programs the low battery threshold voltage
(VBATT.Th). The VTH.A pin is designed to accommodate
voltages from 0V to 1.5V with respect to ground. This
allows the low battery threshold voltage to be set to any
voltage between 2.5V and 3.25V, that is:
(V
)
VBATT .Th = 2.5V + TH.A
2
For instance, if the applied voltage at pin 3, VTH.A, is 1V the
LTC1998 will indicate a low battery condition when the
battery voltage pin (BATT) falls below 3V.
The voltage at the threshold adjust pin (VTH.A) can be set
with any voltage source. This pin allows a continuous time
adjustment, that is, the low battery threshold voltage may
be changed at any time. The high input impedance of the
VTH.A pin allows the use of a high valued resistive divider
(to minimize current drain) from the battery to set the
battery low threshold voltage, Figure 2.
+
1
BATT
R1
Li-Ion
LOW BATTERY THRESHOLD VOLTAGE AND
HYSTERESIS ADJUST
3
R2
VTH.A
LTC1998
2
1998 F02
Figure 2. Resistor Divider Sets Threshold
1998f
5
LTC1998
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APPLICATIO S I FOR ATIO
The simple calculations of resistor values R1 and R2 are
illustrated below. Set a value for R1 + R2. This value will
affect the max amount of current drawn from the battery
when fully charged. For instance if R1 + R2 = 1M the
resistive divider will draw 4.1µA when the battery voltage
is 4.1V. Set the desired value of VBATT.Th (this value should
be between 2.5V and 3.25V) that is the value of the battery
voltage that will trip the internal circuitry of the LTC1998
and change the state of the battery low pin (BATTLO).
 5V

Solve for R1 = (R1 + R2) 
– 1
 VBATT .Th 
Example: A Lithium-Ion battery is monitored and a battery
low signal should be issued when it discharges to 2.85V,
that is, VBATT.Th = 2.85V; if (R1 + R2) = 1M, then
R1 = 754.38k and R2 = 245.62k. Choose the closest 1%
value of R1 = 750k and R2 = 243k. Calculate the practical
value for VBATT.Th as it will be slightly different from 2.85V,
due to the use of standard 1% resistor values.
VBATT .Th = 5V
R1 + R2
= 2.849V
R1 + (R1 + R2)
The above low battery threshold of 2.849V is guaranteed
to within 1% even though 1% resistors are used to
program the VTH.A voltage applied to Pin 3.
The programming of the hysteresis threshold adjust pin
(VH.A) is similar to the programming of the voltage threshold adjust pin (VTH.A) already described in the previous
paragraph. Pin 4 effectively adjusts the threshold voltage
at which the low battery pin (BATTLO) changes state from
low to high. This threshold (VTH2) is defined as:
VTH2 = 2.5V +
The actual hysteresis voltage is:
VHYST = VTH2 – VBATT.Th
It is imperative that the hysteresis threshold adjust voltage
at Pin 4 be set to a higher voltage than the low battery
threshold adjust voltage at Pin 3, at all times, to avoid
oscillation at the BATTLO output pin. The hysteresis
threshold adjust pin may be set with a voltage source or
with a resistor divider, just as with the low battery threshold adjust pin.
Combined Control of Threshold and Hysteresis
If a resistor divider is desired, then both threshold adjust
dividers can be combined in order to save current. This
simple technique also guarantees that the hysteresis threshold adjust voltage at Pin 4 is higher than the voltage at the
VTH.A pin, Figure 3.
For sake of completeness, the voltage at Pin 3 (VTH.A) can
be easily calculated by VTH.A = VBATT.Th (R2/(R1 + R2) =
0.6972V (when VBATTERY = VBATT.Th).
The LTC1998 has an adjustable hysteresis ranging from
10mV to 0.75V. A large hysteresis is useful in the event
that a low battery signal at the LTC1998’s BATTLO pin
causes the system to shed some battery load, thus inducing system confusion as the partially loaded battery recovers and changes the status of Pin 6 (BATTLO). The 2.5V to
3.25V programming window of low battery threshold
voltage includes the hysteresis. If, for instance, the low
battery threshold voltage is set to 2.5V, 750mV hysteresis
can be added on top of the 2.5V. If the low battery
threshold voltage is set to 3.15V, only 100mV hysteresis
can be applied.
+
Li-Ion
Hysteresis Adjustment, Pin 4.
(VH.A )
2
R1
4
1
BATT
VH.A
LTC1998
R2
3
VTH.A
R3
1998 F03
Figure 3. Combined Resistor Divider
The calculation of the resistor values R1, R2 and R3 is
quite straightforward and similar to the procedure outlined in the previous paragraph.
Choose a value for the sum of R1 + R2 + R3 as well as the
values for low battery threshold and hysteresis.
Solve for resistor R1:
1998f
6
LTC1998
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APPLICATIO S I FOR ATIO
 5V

R1 = (R1 + R2 + R3) 
– 1
 VTH2 
has a separate supply pin, (VLOGIC) that can be used to
provide an output voltage rail matching the VDD logic of
microprocessors. The VLOGIC pin may be tied to a voltage
lower than the voltage at the BATT pin. The VLOGIC pin may
also be tied to a voltage higher than VBATT via a series
resistor greater than 10kΩ. The output will then act as an
open-drain device.
Solve for the sum of
 5V

(R1 + R2) = (R1 + R2 + R3) 
– 1
 VBATT .Th 
then solve for R2 and R3.
Example: A system needs to detect a low battery voltage of
3V (VBATT.Th = 3V) with 250mV hysteresis (VTH2 = 3.25V).
Set the value of the resistor divider (R1 + R2 + R3) = 1M.
R1 = 539k, R1 + R2 = 667k, R2 = 128k, R3 = 333k. Choose
the closest 1% values, that is 536k, 332k, 127k. Figure 4
graphically shows the function of the LTC1998 as
described above.
In a given application, if it is possible for BATTLO to be
shorted to GND or a supply, a series resistor should be
added to limit the short-circuit current to 5mA.
3.25V
PROGRAMMED
HYSTERESIS
THRESHOLD
HYSTERESIS
PROGRAMMABLE
THRESHOLD RANGE
PROGRAMMED
LOW BATT
THRESHOLD
2.50V
BATTERY VOLTAGE
RECOVERS UNDER
REDUCED LOAD
BATTERY
VOLTAGE
VERSATILE OUTPUT DRIVER
VLOGIC
VLOGIC, BATTLO (Pins 5,6)
BATTLO
The LTC1998 uses a CMOS push-pull output stage to drive
the low battery output signal. This output pin (BATTLO)
1998 F04
Figure 4. LTC1998 Function Plot
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PACKAGE DESCRIPTIO
S6 Package
6-Lead Plastic TSOT-23
(Reference LTC DWG # 05-08-1636)
0.62
MAX
2.90 BSC
(NOTE 4)
0.95
REF
1.22 REF
3.85 MAX 2.62 REF
1.4 MIN
2.80 BSC
1.50 – 1.75
(NOTE 4)
PIN ONE ID
RECOMMENDED SOLDER PAD LAYOUT
PER IPC CALCULATOR
NOTE:
1. DIMENSIONS ARE IN MILLIMETERS
2. DRAWING NOT TO SCALE
3. DIMENSIONS ARE INCLUSIVE OF PLATING
4. DIMENSIONS ARE EXCLUSIVE OF MOLD
FLASH AND METAL BURR
5. MOLD FLASH SHALL NOT EXCEED 0.254mm
6. JEDEC PACKAGE REFERENCE IS MO-193
0.30 – 0.45
6 PLCS (NOTE 3)
0.95 BSC
0.20 BSC
0.01 – 0.10
1.00 MAX
DATUM ‘A’
0.80 – 0.90
0.30 – 0.50 REF
0.09 – 0.20
(NOTE 3)
1.90 BSC
S6 TSOT-23 0302
1998f
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.
7
LTC1998
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TYPICAL APPLICATIO S
Backup Battery Switchover Circuit
Single Li-Ion Cell Low Battery Detector
VLOGIC =
1V TO 5V
VBATT =
1.5V TO 4.2V
REGULATOR
0.1µF
1
BATT
5
4
VH.A VLOGIC
R2
1%
LTC1998
3
R3
1%
+
Li-Ion
R1
1%
Li-Ion
+
MBRM120
2.5V TO 4.2V
µP
6
VTH.A BATTLO
GND
2
R1
787k
1% 4
R2
68.1k
1% 3
R3
147k
1%
VOUT
BAT54C
R4
1M
1
BATT
5
VH.A VLOGIC
Si2301
Si2301
LTC1998
VTH.A BATTLO
GND
2
BAT54C
6
+
3V
BACKUP
BATTERY
1998 TA01
SWITCHES TO BACKUP BATTERY WHEN PRIMARY FALLS BELOW 2.7V.
SWITCHES BACK TO PRIMARY WHEN VOLTAGE RECOVERS TO ≥ 2.8V
1998 TA04
Micropower 2.9V VCC Threshold
Detector with 15mV Hysteresis
High Accuracy Window Comparator
with Dual Hysteresis
3.3V
R1
715k
1% 4
R2
9.09k
1% 3
R3
274k
1%
1
VIN
BATT
5
VH.A VLOGIC
R1
619k
1% 4
LTC1998
VTH.A BATTLO
GND
2
6
OUT
R2
6.04k
1% 3
LOW THRESHOLD = 2.9V
HYSTERESIS = 15mV
R3
383k
1%
1998 TA03
Low Battery Load Reduction Circuit
R4
909k
1% 4
REGULATOR
Li-Ion
+
R1
787k
1% 4
R2
68.1k
1% 3
R3
147k
1%
Si2301
1
BATT
5
VH.A VLOGIC
CRITICAL
CIRCUITRY
LTC1998
6
VTH.A BATTLO
GND
2
NONCRITICAL
CIRCUITRY
LOW THRESHOLD = 2.7V
HYSTERESIS = 100mV
R5
6.98k
1% 3
R6
76.8k
1%
V+
1
R7
1M
BATT
5
VH.A VLOGIC
VOUT
LTC1998
VTH.A BATTLO
GND
2
6
2N7002
VOUT = V + WHEN
2.6V ≤ VIN ≤ 3.1V
1
BATT
5
NC
VH.A VLOGIC
LTC1998
VTH.A BATTLO
GND
2
6
WINDOW LOW THRESHOLD = 2.6V
HYSTERESIS = 10mV
WINDOW HIGH THRESHOLD = 3.1V
HYSTERESIS = 10mV
1998 TA06
1998 TA05
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LTC1440/LTC1540
Micropower Comparator with 1% Reference
1.182V ±1% Reference, ±10mV (Max) Input Offset
LTC1441/LTC1442
Micropower Dual Comparator with 1% Reference
1.182V ±1% Reference (LTC1442)
LTC1443/LTC1444/LTC1445
Micropower Quad Comparator with 1% Reference
LTC1443 has 1.182V Reference, LTC1444/LTC1445 have 1.221V
Reference and Adjustable Hysteresis
1998f
8
Linear Technology Corporation
LT/TP 0802 2K • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
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www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2001