LTC4066EUF#TRPBF Linear Technology, LTC4066EUF#TRPBF Datasheet - Page 21
LTC4066EUF#TRPBF
Manufacturer Part Number
LTC4066EUF#TRPBF
Description
IC USB POWER MANAGER 24-QFN
Manufacturer
Linear Technology
Datasheet
1.LTC4066EUFPBF.pdf
(28 pages)
Specifications of LTC4066EUF#TRPBF
Function
Power Management
Battery Type
Lithium-Ion (Li-Ion)
Voltage - Supply
4.35 V ~ 5.5 V
Operating Temperature
-40°C ~ 85°C
Mounting Type
Surface Mount
Package / Case
24-WFQFN Exposed Pad
Output Current
1.5A
Output Voltage
4.2V
Operating Supply Voltage (min)
4.35V
Operating Supply Voltage (max)
5.5V
Operating Temp Range
-40C to 85C
Mounting
Surface Mount
Pin Count
24
Operating Temperature Classification
Industrial
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
APPLICATIONS INFORMATION
Power conscious designs may want to use thermistors
whose room temperature value is greater than 10k. Vishay
Dale has a number of values of thermistor from 10k to
100k that follow the “R-T Curve 2.” Using these directly
in the manor spelled out previously in the NTC Thermistor
section will give temperature trip points of approximately
3°C and 47°C, a delta of 44°C. This delta in temperature
can be moved in either direction by changing the value of
R
both trip points to lower temperatures. Likewise a decrease
in R
higher temperatures. To calculate R
temperature for example, use the following equation:
where R
cold temperature trip point. If you want to shift the trip points
to higher temperatures, use the following equation:
where R
hot temperature trip point.
Here is an example using a 100k R-T Curve 1 Thermistor
from Vishay Dale. The difference between the trip points
is 44°C, from before, and we want the cold trip point to
be 0°C, which would put the hot trip point at 44°C. The
R
NOM
NOM
R
R
R
NOM
NOM
NOM
NOM
needed is calculated as follows:
with respect to R
COLD
HOT
with respect to R
=
=
=
=
R
R
3 266
2 815
0 4086
2 815
2 815
R
.
.
.
COLD
COLD
.
is the resistance ratio of R
.
HOT
is the resistance ratio of R
•
•
•
100
•
R
R
R
NTC
NTC
NTC
k
Ω =
NTC
at
at
at
NTC
25
25
116
25
. Increasing R
°
°
°
will move the trip points to
C
C
C
k
Ω
NOM
NTC
for a shift to lower
NTC
NOM
at the desired
at the desired
will move
The nearest 1% value for R
used to bias the NTC thermistor to get cold and hot trip
points of approximately 0°C and 44°C respectively. To
extend the delta between the cold and hot trip points,
a resistor (R1) can be added in series with R
Figure 3b). The values of the resistors are calculated as
follows:
where R
R
trip points. Continuing the example from before with a
desired hot trip point of 50°C:
The fi nal solution is as shown if Figure 3b where R
121k, R1 = 13.3k and R
Gas Gauge
The extremely low impedance of the ideal diode between
BAT and OUT (typically 50mΩ) allows users to connect
all of their loads to the OUT pin. Such a confi guration puts
the LTC4066/LTC4066-1 in a unique position whereby it
can monitor all of the current that fl ows into and out of the
battery. Two output pins, I
enable users to monitor and integrate the battery current
for a true gas gauge function.
R
R
COLD
1 100
NOM
R
R
=
=
NOM
1
13 3
=
=
=
are the values of R
.
⎛
⎜
⎝
120 8
2 815 0 4086
k
NOM
R
=
2 815 0 4086
k
.
•
Ω
.
COLD
2 815 0 4086
.
⎡
⎢
⎣
R
,
.
⎛
⎜
⎝
0 4086
13 3
COLD
k
is the value of the bias resistor, R
2 815 0 4086
.
– .
Ω
– .
.
–
.
,
LTC4066/LTC4066-1
– .
R
k is nearest
121
0 4086
–
HOT
.
– .
R
k nearest
HOT
=
⎞
⎟
⎠
NTC
•
100
NTC
(
STAT
R
NOM
= 100k at 25°C.
⎞
⎟
⎠
COLD
1
k
2 815 0 4086
1
• .
%
at the desired temperature
• .
.
(
%
and POL, are provided to
(
3 266 0 3602
is 115k. This is the value
3 266 0 3602
–
R
– .
HOT
– .
– .
)
–
R
HOT
)
)
– .
NTC
HOT
0 3602
21
NOM
(see
4066fc
and
=
⎤
⎥
⎦