LTC4007EUFD-1#TRPBF Linear Technology, LTC4007EUFD-1#TRPBF Datasheet - Page 13

• Manufacturer Part Number: LTC4007EUFD-1#TRPBF
• Description: IC CHARGER BATTERY 4A 24-QFN
• Manufacturer: Linear Technology
• Type: Battery Chargerr

Specifications of LTC4007EUFD-1#TRPBF

• Function: Charge Management
• Battery Type: Lithium-Ion (Li-Ion)
• Voltage - Supply: 6 V ~ 28 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 24-WFQFN Exposed Pad
• Output Current: 4A
• Output Voltage: 4.1/4.2V
• Operating Supply Voltage (min): 6V
• Operating Supply Voltage (max): 28V
• Operating Temp Range: -40C to 85C
• Package Type: QFN
• Mounting: Surface Mount
• Pin Count: 24
• Operating Temperature Classification: Industrial
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

OPERATIO
the timing resistor connected to R
closed to sample the thermistor:
The external RC network is driven to approximately 4.5V
and settles to a final value across the thermistor of:
This voltage is stored by C7. Then the switch is opened for
a short period of time to read the voltage across the
thermistor.
t
for R
V
SAMPLE
RTH FINAL
RT
(
= 309k
= 127.5 • 20 • R
)
=
U
4 5
R
.
TH
V R
•
+
R
NTC
TH
R
10k
9
TH
RT
• 17.5pF = 13.8ms,
(NOT TO
SCALE)
V
CLK
NTC
T
C7
0.47µF
, keeps switch S1
32.4k
R9
VOLTAGE ACROSS THERMISTOR
7
LTC4007-1
NTC
S1
D
C
Figure 3
Figure 4
Q
When the t
testing is stored in the D flip-flop (DFF). If the voltage at
NTC is within the limits provided by the resistor divider
feeding the comparators, then the NOR gate output will be
low and the DFF will set T
continue. If the voltage at NTC is outside of the resistor
divider limits, then the DFF will set T
will be shut down, FAULT pin is set low and the timer will
be suspended until T
+
–
–
+
COMPARATOR HIGH LIMIT
COMPARATOR LOW LIMIT
t
for R
t
HOLD
HOLD
–
+
t
SAMPLE
RT
= 10 • R
60k
45k
15k
= 309k
HOLD
~4.5V
40071 F03
interval ends the result of the thermistor
RT
CLK
TBAD
• 17.5pF = 54µs,
BAD
40071 F04
returns to zero (see Figure 4).
BAD
to zero and charging will
BAD
LTC4007-1
to one, the charger
13
40071f