RUN Voltage............................................. –0.3V to 150V
SENSE
+
, SENSE
–
Voltages ......................... –0.3V to 65V
FREQ, DRVUV Voltages ............................... –0.3V to 6V
TMR, WARNB Voltages ................................ –0.3V to 6V
EXTV
CC
Voltage ......................................... –0.3V to 14V
ITH, V
FB
Voltages ......................................... –0.3V to 6V
SS, OVLO Voltages ...................................... –0.3V to 6V
Operating Junction Temperature Range (Notes 2, 3)
LTC7862E, LTC7862I ......................... –40°C to 125°C
LTC7862H .......................................... –40°C to 150°C
Storage Temperature Range .................. –65°C to 150°C
PIN CONFIGURATION
TOP VIEW
SENSE
–
SENSE
+
SENSE
+
SENSE
–
SS
V
FB
ITH
TMR
FREQ
WARNB
TG
1
2
3
4
5
6
7
8
9
21
20 OVLO
19 INTV
CC
18 DRVUV
17 RUN
16 EXTV
CC
15 V
IN
14 DRV
CC
13 GND
12 BG
11 BOOST
SS 1
V
FB
2
ITH 3
TMR 4
FREQ 5
WARNB 6
7
TG
8
SW
9 10
BOOST
BG
21
INTV
CC
16 DRVUV
15 RUN
14 EXTV
CC
13 V
IN
12 DRV
CC
11 GND
TOP VIEW
OVLO
20 19 18 17
SW 10
FE PACKAGE
20-LEAD PLASTIC TSSOP
T
JMAX
= 150°C,
θ
JA
= 38°C/W,
θ
JC
= 10°C/W
EXPOSED PAD (PIN 21) IS GND, MUST BE
SOLDERED TO PCB FOR RATED ELECTRICAL AND
THERMAL CHARACTERISTICS
UFD PACKAGE
20-LEAD (4mm × 5mm) PLASTIC QFN
T
JMAX
= 150°C,
θ
JA
= 43°C/W,
θ
JC
= 3.4°C/W
EXPOSED PAD (PIN 21) IS GND, MUST BE
SOLDERED TO PCB FOR RATED ELECTRICAL AND
THERMAL CHARACTERISTICS
ORDER INFORMATION
LEAD FREE FINISH
LTC7862EFE#PBF
LTC7862IFE#PBF
LTC7862HFE#PBF
LTC7862EUFD#PBF
LTC7862IUFD#PBF
LTC7862HUFD#PBF
TAPE AND REEL
LTC7862EFE#TRPBF
LTC7862IFE#TRPBF
LTC7862HFE#TRPBF
LTC7862EUFD#TRPBF
LTC7862IUFD#TRPBF
LTC7862HUFD#TRPBF
http://www.linear.com/product/LTC7862#orderinfo
PART MARKING
LTC7862FE
LTC7862FE
LTC7862FE
7862
7862
7862
PACKAGE DESCRIPTION
20-Lead Plastic TSSOP
20-Lead Plastic TSSOP
20-Lead Plastic TSSOP
20-Lead (4mm × 5mm) Plastic QFN
20-Lead (4mm × 5mm) Plastic QFN
20-Lead (4mm × 5mm) Plastic QFN
TEMPERATURE RANGE
–40°C to 125°C
–40°C to 125°C
–40°C to 150°C
–40°C to 125°C
–40°C to 125°C
–40°C to 150°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to:
http://www.linear.com/tapeandreel/.
Some packages are available in 500 unit reels through
designated sales channels with #TRMPBF suffix.
Rev 0
2
For more information
www.analog.com
LTC7862
The
l
denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T
A
= 25°C (Note 2), V
IN
= 12V, V
RUN
= 5V, V
EXTVCC
= 0V, V
DRVUV
= 0V
unless otherwise noted.
SYMBOL
V
IN
V
OUT
V
FB
I
FB
PARAMETER
Input Supply Operating Voltage Range
Regulated Output Clamp Voltage Set Point
Regulated Feedback Voltage
(Note 4); ITH Voltage = 1.2V
0°C to 85°C
l
ELECTRICAL CHARACTERISTICS
CONDITIONS
(Note 9) DRVUV = 0V
l
MIN
4
TYP
MAX
140
60
UNITS
V
V
V
V
µA
%/V
%
%
mmho
mA
0.792
0.788
0.800
0.800
–0.006
0.002
0.808
0.812
±0.050
0.02
0.1
–0.1
Feedback Current
Feedback Voltage Line Regulation
Feedback Voltage Load Regulation
(Note 4)
(Note 4) V
IN
= 4.5V to 150V
(Note 4) Measured in Servo Loop,
∆ITH Voltage = 1.2V to 0.7V
(Note 4) Measured in Servo Loop,
∆ITH Voltage = 1.2V to 1.6V
l
l
0.01
–0.01
2
1.2
10
g
m
I
Q
UVLO
Transconductance Amplifier gm
Input DC Supply Current
Shutdown
Undervoltage Lockout
(Note 4) ITH = 1.2V, Sink/Source 5µA
(Note 5) V
FB
= 0.77V
RUN = 0V
DRV
CC
Ramping Up
DRVUV = 0V
DRVUV = INTV
CC
DRV
CC
Ramping Down
DRVUV = 0V
DRVUV = INTV
CC
l
l
l
l
l
20
4.2
7.8
4.0
7.0
1.3
1.3
µA
V
V
V
V
V
mV
V
mV
µs
4.0
7.5
3.6
6.4
1.1
1.1
3.8
6.7
1.2
80
1.2
100
1
V
RUN
ON
V
RUN
Hyst
OVLO
OVLO Hyst
RUN Pin ON Threshold
RUN Pin Hysteresis
Overvoltage Lockout Threshold
OVLO Hysteresis
OVLO Delay
Feedback Overvoltage Protection
V
RUN
Rising
V
OVLO
Rising
l
Measured at V
FB
, Relative to Regulated V
FB
SENSE
+
= SENSE
–
= 28V
In Dropout
V
SS
= 0V
V
FB
= 0.7V, V
SENSE
– = 28V
l
7
10
900
13
±1
%
µA
µA
%
I
SENSE
+
I
SENSE
–
I
SS
SENSE
+
Pin Current
SENSE
–
Pin Current
Maximum TG Duty Factor
Soft-Start Charge Current
100
8
43
10
50
12
57
µA
mV
V
SENSE(MAX)
Maximum Current Sense Threshold
Rev 0
For more information
www.analog.com
3
LTC7862
The
l
denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T
A
= 25°C (Note 2), V
IN
= 12V, V
RUN
= 5V, V
EXTVCC
= 0V, V
DRVUV
= 0V
unless otherwise noted.
SYMBOL
Gate Driver
TG Pull-up On-Resistance
TG Pull-down On-Resistance
BG Pull-up On-Resistance
BG Pull-down On-Resistance
TG Transition Time:
Rise Time
Fall Time
BG Transition Time:
Rise Time
Fall Time
Top Gate Off to Bottom Gate On Delay
Synchronous Switch-On Delay Time
Bottom Gate Off to Top Gate On Delay
Top Switch-On Delay Time
t
ON(MIN)
I
CPUMP
TG Minimum On-Time
Charge Pump Output Current
Charge Pump for High Side Driver Supply
V
BOOST
=16V, V
SW
= 12V, V
FREQ
= 0V
V
BOOST
=19V, V
SW
= 12V, V
FREQ
= 0V
V
EXTVCC
= 0V
7V < V
IN
< 150V, DRVUV = 0V
11V < V
IN
< 150V, DRVUV = INTV
CC
I
CC
= 0mA to 50mA, V
EXTVCC
= 0V
DRVUV = 0V
DRVUV = INTV
CC
7V < V
EXTVCC
< 13V, DRVUV = 0V
11V < V
EXTVCC
< 13V, DRVUV = INTV
CC
I
CC
= 0mA to 50mA
DRVUV = 0V, V
EXTVCC
= 8.5V
DRVUV = INTV
CC
, V
EXTVCC
= 13V
EXTV
CC
Ramping Positive
DRVUV = 0V
DRVUV = INTV
CC
4.5
7.4
5.8
8.6
65
55
µA
µA
V
DRVUV
= INTV
CC
V
DRVUV
= INTV
CC
(Note 6) V
DRVUV
= INTV
CC
C
LOAD
= 3300pF
C
LOAD
= 3300pF
(Note 6) V
DRVUV
= INTV
CC
C
LOAD
= 3300pF
C
LOAD
= 3300pF
C
LOAD
= 3300pF Each Driver, V
DRVUV
= INTV
CC
(Note 6)
C
LOAD
= 3300pF Each Driver, V
DRVUV
= INTV
CC
(Note 6)
(Note 7) V
DRVUV
= INTV
CC
2.2
1.0
2.0
1.0
25
15
25
15
55
50
80
Ω
Ω
Ω
Ω
ns
ns
ns
ns
ns
ns
ns
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
ELECTRICAL CHARACTERISTICS
DRV
CC
LDO Regulator
DRV
CC
Voltage from V
IN
LDO
DRV
CC
Load Regulation from V
IN
LDO
DRV
CC
Voltage from EXTV
CC
LDO
DRV
CC
Load Regulation from
EXTV
CC
LDO
EXTV
CC
LDO Switchover Voltage
EXTV
CC
Hysteresis
INTV
CC
LDO Regulator
V
INTVCC
INTV
CC
Voltage
Programmable Frequency
Programmable Frequency
Programmable Frequency
Low Fixed Frequency
High Fixed Frequency
I
CC
= 0mA to 2mA
R
FREQ
= 25k
R
FREQ
= 65k
R
FREQ
=105k
V
FREQ
= 0V
V
FREQ
= INTV
CC
320
485
375
4.7
5.0
105
440
835
350
535
380
585
505
5.2
V
kHz
kHz
kHz
kHz
kHz
Oscillator and Phase-Locked Loop
5.8
8.6
6.0
9.0
1.4
0.9
6.0
9.0
0.7
0.5
4.7
7.7
250
6.2
9.4
2.5
2.0
6.2
9.4
2.0
2.0
4.9
8.0
V
V
%
%
V
V
%
%
V
V
mV
Rev 0
4
For more information
www.analog.com
LTC7862
The
l
denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T
A
= 25°C (Note 2), V
IN
= 12V, V
RUN
= 5V, V
EXTVCC
= 0V, V
DRVUV
= 0V
unless otherwise noted.
SYMBOL
I
SWITCHING
I
DROPOUT
I
COOLDOWN
PARAMETER
TMR Pull-Up Current (Switching)
TMR Pull-Down Current (Dropout)
TMR Pull-Down Current (Cool-Down)
TMR Switching Off Threshold
TMR Retry Threshold
TMR Switching Set Time
(Initial Fault Period) per 1µF
TMR Switching Set Time
(Retry Period) per 1µF
TMR Cool-Down Time per 1µF
D
RETRY
V
WARNB
I
WARNB
t
WARNB
Retry Duty Cycle During a Sustained Fault
WARNB Voltage Low
WARNB Leakage Current
Delay from TG Going High to WARNB
Going High Impedance
I
WARNB
= 2mA
V
WARNB
= 3.3V
60
1.8
CONDITIONS
TMR = 0V, V
FB
= 0.83V
TMR = 1V, V
FB
= 0.77V
TMR = 2.5V
l
l
l
l
ELECTRICAL CHARACTERISTICS
Fault Timer and WARNB Output
MIN
–35
0.7
0.7
2.13
0.19
52
TYP
–40
1.1
1.1
2.19
0.25
55
50
1700
2.7
0.02
MAX
–45
1.4
1.4
2.23
0.31
58
UNITS
µA
µA
µA
V
V
ms/µF
ms/µF
ms/µF
3.5
0.04
10
%
V
µA
µs
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Ratings for extended periods may affect device reliability and
lifetime.
Note 2:
The LTC7862 is tested under pulsed load conditions such that T
J
≈
T
A
. The LTC7862E is guaranteed to meet performance specifications from
0°C to 85°C. Specifications over the –40°C to 125°C operating junction
temperature range are assured by design, characterization and correlation
with statistical process controls. The LTC7862I is guaranteed over the
–40°C to 125°C operating junction temperature range and the LTC7862H
is guaranteed over the –40°C to 150°C operating junction temperature
range. Note that the maximum ambient temperature consistent with
these specifications is determined by specific operating conditions in
conjunction with board layout, the rated package thermal impedance
and other environmental factors. High temperatures degrade operating
lifetimes; operating lifetime is derated for junction temperatures greater
than 125ºC. The junction temperature (T
J
, in °C) is calculated from the
ambient temperature (T
A
, in °C) and power dissipation (P
D
, in Watts)
according to the formula:
T
J
= T
A
+ (P
D
•
θ
JA
)
where
θ
JA
= 38°C/W for the TSSOP package and
θ
JA
= 43°C/W for the
QFN package.
Note 3:
This IC includes overtemperature protection that is intended to
protect the device during momentary overload conditions. The maximum
rated junction temperature will be exceeded when this protection is active.
Continuous operation above the specified absolute maximum operating
junction temperature may impair device reliability or permanently damage
the device.
Note 4:
The LTC7862 is tested in a feedback loop that servos V
ITH
to a
specified voltage and measures the resultant V
FB
. The specification at
85°C is not tested in production and is assured by design, characterization
and correlation to production testing at other temperatures (125°C for the
LTC7862E and LTC7862I, 150°C for the LTC7862H). For the LTC7862I
and LTC7862H, the specification at 0°C is not tested in production and is
assured by design, characterization and correlation to production testing
at –40°C.
Note 5:
Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See the Applications Information
section.
Note 6:
Rise and fall times are measured using 10% and 90% levels.
Delay times are measured using 50% levels.
Note 7:
The minimum on-time condition is specified for an inductor
peak-to-peak ripple current >40% of I
MAX
(See Minimum On-Time
Considerations in the Applications Information section).
Note 8:
Do not apply a voltage or current source to these pins. They must
be connected to capacitive loads only, otherwise permanent damage may
occur.
Note 9:
The minimum input supply operating range is dependent on the
DRV
CC
UVLO thresholds as determined by the DRVUV pin setting.
Note 10:
All voltages with respect to GND unless otherwise noted. Positive
currents are into pins; negative currents are out of pins unless otherwise
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