applications that allows a board to be safely inserted and
removed from a live backplane. The part integrates a Hot
Swap controller, power MOSFET and current sense resistor
in a single package for small form factor applications. A
dedicated 12V version (LTC4217-12) contains preset 12V
specific thresholds, while the standard LTC4217 allows
adjustable thresholds.
The LTC4217 provides separate inrush current control and a
5% accurate 2A current limit with foldback current limiting.
The current limit threshold can be adjusted dynamically
using an external pin. Additional features include a current
monitor output that amplifies the sense resistor voltage
for ground referenced current sensing and a MOSFET
temperature monitor output. Thermal limit, overvoltage,
undervoltage and power good monitoring are also provided.
For a 5A pin compatible version, see LTC4232.
L,
LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Small Footprint
33mΩ MOSFET with R
SENSE
Wide Operating Voltage Range: 2.9V to 26.5V
Adjustable, 5% Accurate Current Limit
Current and Temperature Monitor Outputs
Overtemperature Protection
Adjustable Current Limit Timer Before Fault
Power Good and Fault Outputs
Adjustable Inrush Current Control
2% Accurate Undervoltage and Overvoltage Protection
Pin Compatible with LTC4232 (DFN Package Only)
Available in 20-Lead TSSOP and 16-Lead
5mm × 3mm DFN Packages
applicaTions
n
n
n
RAID Systems, Solid State Drives
Server I/O Cards
Industrial
Typical applicaTion
12V, 1.5A Card Resident Application with Auto-Retry
12V
V
DD
UV
LTC4217DHC-12
FLT
TIMER
INTV
CC
1µF
GND
PG
GATE
I
SET
I
MON
20k
4217 TA01a
Power-Up Waveforms
V
IN
10V/DIV
I
IN
0.1A/DIV
V
OUT
10V/DIV
P
G
10V/DIV
25ms/DIV
4217 TA01b
*
AUTO
RETRY
OUT
10k
+
V
OUT
12V
330µF 1.5A
CONTACT
BOUNCE
ADC
* TVS: DIODES INC. SMAJ17A
4217fg
For more information
www.linear.com/LTC4217
1
LTC4217
absoluTe MaxiMuM raTings
(Notes 1, 2)
Supply Voltage (V
DD
) ................................. –0.3V to 28V
Input Voltages
FB, OV, UV ..............................................–0.3V to 12V
TIMER ................................................... –0.3V to 3.5V
SENSE ............................. V
DD
– 10V or – 0.3V to V
DD
Output Voltages
I
SET
, I
MON
................................................. –0.3V to 3V
PG,
FLT
.................................................. –0.3V to 35V
OUT ............................................ –0.3V to V
DD
+ 0.3V
INTV
CC
.................................................. –0.3V to 3.5V
GATE (Note 3) ........................................ –0.3V to 33V
Operating Ambient Temperature Range
LTC4217C ................................................ 0°C to 70°C
LTC4217I .............................................–40°C to 85°C
LTC4217H .......................................... –40°C to 125°C
Junction Temperature (Notes 4, 5)........................ 125°C
Storage Temperature Range .................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec)
FE Package Only ............................................... 300°C
pin conFiguraTion
LTC4217
LTC4217-12
TOP VIEW
V
DD
UV
OV
TIMER
INTV
CC
GND
OUT
OUT
1
2
3
4
5
6
7
8
17
SENSE
16 V
DD
15 I
SET
14 I
MON
13 FB
12
FLT
11 PG
10 GATE
9
OUT
LTC4217
TOP VIEW
SENSE
V
DD
UV
OV
TIMER
INTV
CC
GND
OUT
OUT
1
2
3
4
5
6
7
8
9
21
SENSE
20 SENSE
19 V
DD
18 I
SET
17 I
MON
16 FB
15 FLT
14 PG
13 GATE
12 OUT
11 SENSE
DHC PACKAGE
16-LEAD (5mm
×
3mm) PLASTIC DFN
T
JMAX
= 125°C,
θ
JA
= 43°C/W
EXPOSED PAD (PIN 17) IS SENSE,
θ
JA
= 43°C/W SOLDERED, OTHERWISE
θ
JA
= 140°C/W
SENSE 10
FE PACKAGE
20-LEAD PLASTIC TSSOP
T
JMAX
= 125°C,
θ
JA
= 38°C/W
EXPOSED PAD (PIN 21) IS SENSE,
θ
JA
= 38°C/W SOLDERED, OTHERWISE
θ
JA
= 130°C/W
2
4217fg
For more information
www.linear.com/LTC4217
LTC4217
orDer inForMaTion
LEAD FREE FINISH
LTC4217CDHC-12#PBF
LTC4217IDHC-12#PBF
LTC4217CDHC#PBF
LTC4217IDHC#PBF
LTC4217CFE#PBF
LTC4217IFE#PBF
LTC4217HFE#PBF
TAPE AND REEL
LTC4217CDHC-12#TRPBF
LTC4217IDHC-12#TRPBF
LTC4217CDHC#TRPBF
LTC4217IDHC#TRPBF
LTC4217CFE#TRPBF
LTC4217IFE#TRPBF
LTC4217HFE#TRPBF
(http://www.linear.com/product/LTC4217#orderinfo)
PART MARKING*
421712
421712
4217
4217
LTC4217FE
LTC4217FE
LTC4217FE
PACKAGE DESCRIPTION
16-Lead (5mm × 3mm) Plastic DFN
16-Lead (5mm × 3mm) Plastic DFN
16-Lead (5mm × 3mm) Plastic DFN
16-Lead (5mm × 3mm) Plastic DFN
20-Lead Plastic TSSOP
20-Lead Plastic TSSOP
20-Lead Plastic TSSOP
TEMPERATURE RANGE
0°C to 70°C
–40°C to 85°C
0°C to 70°C
–40°C to 85°C
0°C to 70°C
–40°C to 85°C
–40°C to 125°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.
elecTrical characTerisTics
SYMBOL
V
DD
I
DD
V
DD(UVL)
V
DD(UVTH)
V
DD(OVTH)
V
OUT(PGTH)
I
OUT
PARAMETER
Input Supply Range
Input Supply Current
Input Supply Undervoltage Lockout
Input Supply Undervoltage Threshold
Input Supply Overvoltage Threshold
Output Power Good Threshold
OUT Leakage Current
DC Characteristics
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
DD
= 12V unless otherwise noted.
CONDITIONS
l
MIN
2.9
TYP
MAX
26.5
UNITS
V
mA
V
V
mV
V
mV
V
mV
µA
µA
µA
µA
V/ms
mΩ
mΩ
A
A
A
A
MOSFET On, No Load
V
DD
Rising
LTC4217-12, V
DD
Rising
LTC4217-12
LTC4217-12, V
DD
Rising
LTC4217-12
LTC4217-12, V
OUT
Rising
LTC4217-12
V
OUT
= V
GATE
= 0V, V
DD
= 26.5V
V
OUT
= V
GATE
= 12V, LTC4217
V
OUT
= V
GATE
= 12V, LTC4217-12
V
OUT
= V
GATE
= 12V, LTC4217H
C-Grade, I-Grade
H-Grade
V
FB
= 1.23V
V
FB
= 1.23V
V
FB
= 0V
V
FB
= 1.23V, R
SET
= 20kΩ
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
1.6
2.65
9.6
520
14.7
183
10.2
127
1
50
1
0.15
15
15
1.9
1.85
0.35
0.85
2.73
9.88
640
15.05
244
10.5
170
0
2
70
2
0.3
33
33
2
2
0.5
1
3
2.85
10.2
760
15.4
305
10.8
213
±150
4
90
6
0.55
50
60
2.1
2.15
0.7
1.17
∆V
DD(UVHYST)
Input Supply Undervoltage Hysteresis
∆V
DD(OVHYST)
Input Supply Overvoltage Hysteresis
∆V
OUT(PGHYST)
Output Power Good Hysteresis
dV
GATE
/dt
R
ON
I
LIM(TH)
GATE Pin Turn-On Ramp Rate
MOSFET + Sense Resistor On-Resistance
Current Limit Threshold
l
l
l
4217fg
For more information
www.linear.com/LTC4217
3
LTC4217
elecTrical characTerisTics
SYMBOL
Inputs
I
IN
R
IN
V
TH
∆V
OV(HYST)
∆V
UV(HYST)
V
UV(RTH)
∆V
FB(HYST)
R
ISET
Outputs
V
OL
I
OH
V
TIMER(H)
V
TIMER(L)
I
TIMER(UP)
I
TIMER(DN)
I
TIMER(RATIO)
A
IMON
BW
IMON
I
OFF(IMON)
I
GATE(UP)
I
GATE(DN)
I
GATE(FST)
t
PHL(GATE)
t
PHL(ILIM)
t
D(ON)
t
D(FAULT)
t
D(CB)
PG,
FLT
Pin Output Low Voltage
I
SINK
= 2mA
C-Grade, I-Grade
H-Grade
30V
V
TIMER
Rising
V
TIMER
Falling
V
TIMER
= 0V
V
TIMER
= 1.2V
I
OUT
= 2A
I
OUT
= 132mA
Gate Drive On, V
GATE
= V
OUT
= 12V
Gate Drive Off, V
GATE
= 18V, V
OUT
= 12V
C-Grade, I-Grade
H-Grade
Fast Turn Off, V
GATE
= 18V, V
OUT
= 12V
V
GATE
< 16.5V Falling
V
FB
= 0, Step I
SENSE
to 1.2A,
V
GATE
< 16.5V Falling
Step V
UV
to 2V, V
GATE
> 13V
V
FB
= 0V, Step I
SENSE
to 1.2A
C-Grade, I-Grade
H-Grade
l
l
l
l
l
l
l
l
l
l
l
l
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
DD
= 12V unless otherwise noted.
PARAMETER
OV, UV, FB Input Current
OV, UV, FB Input Resistance
OV, UV, FB Threshold Voltage
OV Hysteresis
UV Hysteresis
UV Reset Threshold Voltage
FB Power Good Hysteresis
I
SET
Internal Resistor
V
UV
Falling
CONDITIONS
V = 1.2V, LTC4217
LTC4217-12
V
PIN
Rising
l
l
l
l
l
l
l
l
MIN
TYP
0
MAX
±1
23
1.26
30
110
0.7
30
21
UNITS
µA
kΩ
V
mV
mV
V
mV
kΩ
13
1.21
10
50
0.55
10
19
18
1.235
20
80
0.62
20
20
0.4
0.4
0
1.2
0.1
–80
1.4
1.6
47.5
1.235
0.21
–100
2
2
50
250
0
–19
190
164
–24
250
140
140
8
1
50
100
1
0.8
0.92
±10
1.28
0.3
–120
2.6
2.7
52.5
±7.5
–29
400
500
V
V
µA
V
V
µA
µA
%
µA/A
kHz
µA
µA
µA
µA
mA
PG,
FLT
Pin Input Leakage Current
TIMER Pin High Threshold
TIMER Pin Low Threshold
TIMER Pin Pull-Up Current
TIMER Pin Pull-Down Current
TIMER Pin Current Ratio I
TIMER(DN)
/I
TIMER(UP)
I
MON
Pin Current Gain
I
MON
Bandwidth
I
MON
Pin Offset Current
Gate Pull-Up Current
Gate Pull-Down Current
l
l
l
l
Gate Fast Pull-Down Current
Input High (OV), Input Low (UV) to Gate Low
Propagation Delay
Short-Circuit to Gate Low
Turn-On Delay
UV Low to Clear Fault Latch Delay
Circuit Breaker Filter Delay Time (Internal)
AC Characteristics
10
5
150
µs
µs
ms
µs
2.7
2.7
150
ms
ms
ms
l
l
l
1.5
1.4
50
2
2
100
t
D(AUTO-RETRY)
Auto-Retry Turn-On Delay (Internal)
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
All currents into pins are positive, all voltages are referenced to
GND unless otherwise specified.
Note 3:
An internal clamp limits the GATE pin to a maximum of 6.5V above
OUT. Driving this pin to voltages beyond the clamp may damage the device.
4
Note 4:
This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed 125°C when overtemperature protection is active.
Continuous operation above the specified maximum operating junction
据外媒报道,萨里大学(University of Surrey)的研究人员开发出一种无需依赖GPS即可在人口密集的城市地区精确定位设备位置的人工智能系统。该系统可将定位误差从734米缩小到22米以内,这对于自动驾驶汽车和救援车辆等技术的发展意义重大。 图片来源: 萨里大学 在发表于《IEEE Robotics and Automation Letters》的论文中,研究人员介绍了PEn...[详细]