16
LT1494/LT1495/LT1496
LINEAR TECHNOLOGY CORPORATION 1997
149456fb LT/TP 0801 1.5K REV B • PRINTED IN USA
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
●
(408) 432-1900
FAX: (408) 434-0507
●
TELEX: 499-3977
●
www.linear.com
Battery Current Monitor
0nA to 200nA Current Meter
TYPICAL APPLICATIONS N
U
RELATED PARTS
–
+
–
+
1495 TA05
R
SENSE
0.1Ω
I
L
CHARGE
R
A
2N3904
V
O
= I
L
R
SENSE
FOR R
A
= 1k, R
B
= 10k
= 1V/A
CHARGE
OUT
DISCHARGE
OUT
DISCHARGE
2N3904
R
A
R
A
R
A
R
B
R
B
R
A
V
O
I
L
R
B
A1
1/2 LT1495
5V
12V
A2
1/2 LT1495
()
–
+
–
+
µA
1495 TA06
1/2
LT1495
1/2
LT1495
100pF
R1
10M
R2
9k
1.5V
1.5V
R3
2k
FULL-SCALE
ADJUST
I
S
= 3µA WHEN I
IN
= 0
NO ON/OFF SWITCH
REQUIRED
0µA TO
200µA
R4
10k
INPUT
CURRENT
High Side Current Sense
PART NUMBER DESCRIPTION COMMENTS
LTC
®
1440/41/42 Micropower Single/Dual Comparators with 1% Reference LTC1440: Single, LTC1441/42: Dual
LTC1443/44/45 Micropower Quad Comparators with 1% Reference LTC1443: 1.182 Reference
LTC1444/45: 1.221V Reference and Adjustable Hysteresis
LT1466/LT1467 75µA Dual/Quad Rail-to-Rail Input and Output Op Amps 390µV V
OS(MAX)
, Gain Bandwidth = 120kHz
LT1490A/LT1491A 50µA Dual/Quad Rail-to-Rail Input and Output Op Amps 950µV V
OS(MAX)
, Gain Bandwidth = 200kHz
LTC1540 Nanopower Single Comparator with 1% Reference 350nA Supply Current
LT1636 Single Over-The-Top Micropower, 225µV V
OS(MAX)
, I
S
= 55µA (MAX), Gain-Bandwidth = 200kHz
Rail-to-Rail Input and Output Op Amp Shutdown Pin, MSOP
LT1672/LT1673/LT1674 2µA MAX, A
V
≥ 5 Single/Dual/Quad Over-The-Top Precision Decompensated Version of the LT1494/LT1495/LT1496
Rail-to-Rail Input and Output Op Amps A
V
≥ 5, Gain-Bandwidth = 12kHz
LT2078/LT2079 55µA Dual/Quad Single Supply Op Amps 120µV V
OS(MAX)
, Gain Bandwidth = 200kHz
LT2178/LT2179 17µA Dual/Quad Single Supply Op Amps 120µV V
OS(MAX)
, Gain Bandwidth = 60kHz
LT1782 Micropower, Over-The-Top, SOT-23, Rail-to-Rail SOT-23, 800µV V
OS(MAX)
, I
S
= 55µA (Max),
Input and Output Op Amp Gain-Bandwidth = 200kHz, Shutdown Pin
LT1783 1.2MHz, Over-The-Top, Micropower, Rail-to-Rail SOT-23, 800µV V
OS(MAX)
, I
S
= 300µA (Max),
Input and Output Op Amp in SOT-23 Gain-Bandwidth = 1.2MHz, Shutdown Pin
+
–
LT1494
R
A
1k
R
SENSE
1Ω
LOAD
I
L
V
S
= 2.7V TO 36V
1495 TA09
R
B
10k
+
_
V
O
( )
R
B
R
A
V
O
= I
L
R
S
FOR R
A
= 1k, R
B
= 10k, R
S
= 1Ω
= 10 V/A
OUTPUT OFFSET ≈ I
S
• R
B
≈ 10mV
OUTPUT CLIPS AT V
S
– 2.4V
V
O
I
L
