allows a board to be safely inserted and removed from
a live AMC or MicroTCA backplane. It controls the main
12V supply with an external N-channel MOSFET and the
3.3V auxiliary supply with an integrated switch. The 12V
output ramp rate is adjustable and includes inrush current
limiting. The 12V output is also protected against short
circuit faults with a fast acting current limit and a 5%
accurate timed circuit breaker. The 3.3V output includes
both soft start and overcurrent protection.
The LTC4223 features a current monitor output for the
12V supply, and reports fault and power-good status for
both supplies. It also detects card presence and allows
independent control of the 12V and auxiliary 3.3V sup-
ply outputs. The LTC4223-1 features a latch-off circuit
breaker, while the LTC4223-2 provides automatic retry
after a fault.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
Allows Safe Insertion into Live AMC or MicroTCA
Backplane
Controls 12V Main and 3.3V Auxiliary Supplies
Limits Peak Fault Current in ≤1μs
Adjustable Current Limit with Circuit Breaker
Integrated 0.3Ω AUX Switch
High Side Current Sense
Gate Drive for External N-Channel MOSFET
Adjustable Response Time for Overcurrent Protection
Adjustable Supply Voltage Power-Up Rate
Thermal Shutdown Protection
LTC4223-1: Latch Off After Fault
LTC4223-2: Automatic Retry After Fault
16-Lead SSOP and 5mm
×
4mm DFN Packages
APPLICATIONS
■
■
■
Advanced Mezzanine Card, MicroTCA Systems
Workstations and Server I/O
Telecom Networks
TYPICAL APPLICATION
Advanced Mezzanine Card Application
6mΩ
12V
Si7336ADP
12V
7.4A
15nF
Normal Power-Up Waveform
EN
5V/DIV
AUXOUT
5V/DIV
10Ω
47Ω
12V
IN
12V
SENSE
12V
GATE
12V
OUT
3.3V
150mA
12V
OUT
5V/DIV
AUXPGOOD
5V/DIV
12PGOOD
5V/DIV
3.3V
51Ω
AUXIN
AUXOUT
V
CC
330nF
AUXON
12ON
AUXPGOOD
12PGOOD
FAULT
IPMC
ADC
12IMON
GND
TIMER
0.1μF
422312 TA01a
LTC4223-1/LTC4223-2
20ms/DIV
422312 TA01b
EN
CARRIER MODULE
CONNECTOR CONNECTOR
422312f
1
LTC4223-1/LTC4223-2
ABSOLUTE MAXIMUM RATINGS
(Note 1)
Supply Voltages
12V
IN
..................................................... –0.3V to 20V
AUXIN .................................................... –0.3V to 10V
V
CC
........................................................... –0.3V to 7V
Input Voltages
12ON, AUXON,
⎯
E
⎯
N ................................... –0.3V to 7V
TIMER..........................................–0.3V to V
CC
+ 0.3V
12V
SENSE
............................................... –0.3V to 20V
Output Voltages
⎯
F
⎯
A
⎯
U
⎯
L
⎯
T,
⎯
1
⎯
2
⎯
P
⎯
G
⎯
O
⎯
O
⎯
D,
⎯
A
⎯
U
⎯
X
⎯
P
⎯
G
⎯
O
⎯
O
⎯
D,
12IMON ................................................... –0.3V to 7V
12V
GATE
................................................. –0.3V to 25V
12V
OUT
- 12V
GATE
(Note 3) ................... –4.5V to 0.3V
AUXOUT................................................. –0.3V to 10V
Operating Temperature Range
LTC4223-1C/ LTC4223-2C ....................... 0°C to 70°C
LTC4223-1I/ LTC4223-2I ..................... –40°C to 85°C
Storage Temperature Range
GN Package ....................................... –65°C to 150°C
DHD Package ..................................... –65°C to 125°C
Lead Temperature (Soldering, 10sec)
GN Package ...................................................... 300°C
PIN CONFIGURATION
TOP VIEW
TOP VIEW
12V
SENSE
12V
IN
12IMON
12ON
AUXIN
V
CC
AUXON
GND
1
2
3
4
5
6
7
8
16 12V
GATE
15 12V
OUT
14 12PGOOD
13 FAULT
12 AUXOUT
11 AUXPGOOD
10 EN
9
TIMER
DHD PACKAGE
16-LEAD (5mm
×
4mm) PLASTIC DFN
12V
SENSE
12V
IN
12IMON
12ON
AUXIN
V
CC
AUXON
GND
1
2
3
4
5
6
7
8
17
16 12V
GATE
15 12V
OUT
14 12PGOOD
13 FAULT
12 AUXOUT
11 AUXPGOOD
10 EN
9
TIMER
GN PACKAGE
16-LEAD PLASTIC SSOP
T
JMAX
= 125°C,
θ
JA
= 110°C/W
EXPOSED PAD (PIN 17) PCB GND CONNECTION OPTIONAL
MUST BE SOLDERED TO PCB TO OBTAIN
θ
JA
= 43°C/W, OTHERWISE
θ
JA
= 140°C/W, T
JMAX
= 125°C
ORDER INFORMATION
LEAD FREE FINISH
LTC4223CDHD-1#PBF
LTC4223CDHD-2#PBF
LTC4223IDHD-1#PBF
LTC4223IDHD-2#PBF
LTC4223CGN-1#PBF
LTC4223CGN-2#PBF
LTC4223IGN-1#PBF
LTC4223IGN-2#PBF
TAPE AND REEL
LTC4223CDHD-1#TRPBF
LTC4223CDHD-2#TRPBF
LTC4223IDHD-1#TRPBF
LTC4223IDHD-2#TRPBF
LTC4223CGN-1#TRPBF
LTC4223CGN-2#TRPBF
LTC4223IGN-1#TRPBF
LTC4223IGN-2#TRPBF
PART MARKING*
42231
42232
42231
42232
42231
42232
4223I1
4223I2
PACKAGE DESCRIPTION
16-Lead (5mm
×
4mm) Plastic DFN
16-Lead (5mm
×
4mm) Plastic DFN
16-Lead (5mm
×
4mm) Plastic DFN
16-Lead (5mm
×
4mm) Plastic DFN
16-Lead Plastic SSOP
16-Lead Plastic SSOP
16-Lead Plastic SSOP
16-Lead Plastic SSOP
TEMPERATURE RANGE
0°C to 70°C
0°C to 70°C
–40°C to 85°C
–40°C to 85°C
0°C to 70°C
0°C to 70°C
–40°C to 85°C
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
Consult LTC Marketing for information on non-standard lead based finish parts.
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/
422312f
2
LTC4223-1/LTC4223-2
ELECTRICAL CHARACTERISTICS
SYMBOL
Supplies
V
DD
Input Supply Range
V
CC
AUXIN
12V
IN
V
CC
AUXIN
12V
IN
V
CC
Rising
V
AUXIN
Rising
V
12VIN
Rising
V
CC
AUXIN
12V
IN
●
●
●
●
●
●
●
●
●
●
●
●
The
●
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are T
A
= 25°C, V
CC
= 3.3V, V
AUXIN
= 3.3V, V
12VIN
=12V, unless otherwise specified. (Note 2)
PARAMETER
CONDITIONS
MIN
2.7
2.7
10
0.8
0.4
0.6
2.3
2.4
9.4
40
70
70
2.45
2.5
9.7
110
110
110
TYP
MAX
6
6
14
2
1
1
2.6
2.6
10
180
150
150
UNITS
V
V
V
mA
mA
mA
V
V
V
mV
mV
mV
I
DD
Input Supply Current
V
DD(UVLO)
Input Supply Undervoltage Lockout
ΔV
DD(UVLO,
HYST)
Input Supply Undervoltage Lockout
Hysteresis
Current Limit
ΔV
SENSE(CB)
ΔV
SENSE(ACL)
I
AUX(ACL)
R
DS(ON)
Gate Drive
ΔV
GATE
I
GATE(UP)
I
GATE(DN)
I
GATE(FPD)
Current Sense
G
12IMON
V
12IMON
ΔV
SENSE(MAX)
V
12IMON(CLP)
R
12IMON
V
12IMON(MIN)
V
PG(TH)
V
PG(HYST)
V
TMR(TH)
12IMON Pin Gain Ratio
ΔV
12IMON
/Δ(V
12VIN
– V
12VSENSE
)
12IMON Pin Output Voltage
12IMON Pin Maximum Input Sense Voltage
12IMON Pin Clamp Voltage
12IMON Pin Output Resistance
12IMON Pin Minimum Output Voltage
Power Good Threshold Voltage
Power Good Hysteresis
TIMER Pin Threshold Voltage
(V
12VIN
– V
12VSENSE
) = 150mV, V
CC
= 2.7V
(V
12VIN
– V
12VSENSE
) = 0V
(V
12VIN
– V
12VSENSE
) = 0V
V
12VOUT
Falling
V
AUXOUT
Falling
V
12VOUT
V
AUXOUT
V
TIMER
Rising
V
TIMER
Falling
(V
12VIN
– V
12VSENSE
) = (75mV, 25mV)
(V
12VIN
– V
12VSENSE
) = 75mV, V
CC
= 2.7V
●
●
●
●
●
●
Circuit Breaker Trip Sense Voltage,
(V
12VIN
– V
12VSENSE
)
Active Current Limit Sense Voltage,
(V
12VIN
– V
12VSENSE
)
AUXOUT Active Current Limit
Switch Resistance
(V
AUXIN
– V
AUXOUT
)/I
AUXOUT
External N-Channel Gate Drive
(V
12VGATE
– V
12VOUT
)
External N-Channel Gate Pull-Up Current
External N-Channel Gate Pull-Down Current
External N-Channel Gate Fast Pull-Down
Current
V
AUXOUT
= 0V
I
AUXOUT
= 150mA (Note 4)
●
●
●
47.5
54
165
50
60
240
0.3
52.5
66
330
0.5
mV
mV
mA
Ω
Integrated Switch
●
(Note 3)
Gate Drive On, V
12VGATE
= 0V
Gate Drive Off
V
12VGATE
= 17V, V
12VOUT
= 12V
Fast Turn Off
V
12VGATE
= 17V, V
12VOUT
= 12V
●
●
●
●
4.5
–7
0.5
90
6.2
–10
1
160
7.9
–14
2
250
V
μA
mA
mA
30
2.25
82.5
2.9
115
33
2.475
3.2
165
0
36
2.7
3.5
215
130
10.6
2.97
110
30
1.272
0.25
V/V
V
mV
V
kΩ
mV
V
V
mV
mV
V
V
Comparator Inputs
●
●
●
●
●
●
10
2.8
20
5
1.198
0.15
10.3
2.885
60
16
1.235
0.2
422312f
3
LTC4223-1/LTC4223-2
ELECTRICAL CHARACTERISTICS
SYMBOL
I
TMR(UP)
PARAMETER
TIMER Pull-Up Current
The
●
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are T
A
= 25°C, V
CC
= 3.3V, V
AUXIN
= 3.3V, V
12VIN
=12V, unless otherwise specified. (Note 2)
CONDITIONS
V
TIMER
= 1V, Initial Timing Cycle
V
TIMER
= 0V, In AUX Fault Mode
V
TIMER
= 0V, In 12V Fault Mode
V
TIMER
= 2V, No Faults
V
TIMER
= 2V, In Reset Mode
I
OL
= 3mA
(Note 5)
V
PU
= 1.5V
●
●
●
●
●
MIN
–7
–7
–140
1.3
2
TYP
–10
–10
–200
2
8
0.15
MAX
–13
–13
–260
2.6
16
0.4
UNITS
μA
μA
μA
μA
mA
V
V
I
TMR(DN)
TIMER Pull-Down Current
Open Drain Outputs
V
OL
V
OH
I
PU
Logic Inputs
V
IN(TH)
I
IN(LEAK)
R
PU
I
12VSENSE
I
12VOUT
R
OUT(DIS)
Logic Input Threshold (12ON, AUXON,
⎯
E
⎯
N)
Input Leakage Current (12ON, AUXON)
⎯
E
⎯
N Pin Pull-Up Resistance
12V
SENSE
Pin Input Current
12V
OUT
Pin Input Current
OUT Pin Discharge Resistance
12V
OUT
AUXOUT
AUX Circuit Breaker Trip Delay
Sense Voltage, (12V
IN
– 12V
SENSE
)
High to 12V
GATE
Low
AUXON High to AUXOUT High
12ON High to 12V
GATE
High
Input Low (12ON, AUXON) to
⎯
F
⎯
A
⎯
U
⎯
L
⎯
T High
V
CC
Low to
⎯
F
⎯
A
⎯
U
⎯
L
⎯
T High
12V
IN
Low to 12V
GATE
Low
AUXIN Low to
⎯
A
⎯
U
⎯
X
⎯
P
⎯
G
⎯
O
⎯
O
⎯
D High
t
PHL(GATE)
t
PLH(PG)
t
P(12IMON)
⎯
E
⎯
N High to 12V
GATE
Low
12V
OUT
Low to
⎯
1
⎯
2
⎯
P
⎯
G
⎯
O
⎯
O
⎯
D High
AUXOUT Low to
⎯
A
⎯
U
⎯
X
⎯
P
⎯
G
⎯
O
⎯
O
⎯
D High
Input Sense Voltage Step to 12IMON
Propagation Delay
ΔV
SENSE
= 100mV
V
12VSENSE
= 12V
Gate Drive On, V
12VOUT
= 12V
Gate Drive Off
V
12VOUT
= 6V
V
AUXVOUT
= 2V
After Power Up
ΔV
SENSE
= 300mV, C
12VGATE
= 10nF
ΔV
SENSE
= 100mV, C
12VGATE
= 10nF
V
IN
= V
CC
●
●
●
Output Low Voltage (
⎯
F
⎯
A
⎯
U
⎯
L
⎯
T,
⎯
1
⎯
2
⎯
P
⎯
G
⎯
O
⎯
O
⎯
D,
⎯
A
⎯
U
⎯
X
⎯
P
⎯
G
⎯
O
⎯
O
⎯
D)
Output High Voltage (
⎯
F
⎯
A
⎯
U
⎯
L
⎯
T,
⎯
1
⎯
2
⎯
P
⎯
G
⎯
O
⎯
O
⎯
D,
⎯
A
⎯
U
⎯
X
⎯
P
⎯
G
⎯
O
⎯
O
⎯
D)
Output Pin Pull-Up Current (
⎯
F
⎯
A
⎯
U
⎯
L
⎯
T,
⎯
1
⎯
2
⎯
P
⎯
G
⎯
O
⎯
O
⎯
D,
⎯
A
⎯
U
⎯
X
⎯
P
⎯
G
⎯
O
⎯
O
⎯
D)
●
●
●
V
CC
– 1
–6
–10
–14
μA
0.8
60
10
20
400
375
12
100
50
50
800
750
25
0.5
5
15
30
20
80
6
6
12
12
20
20
20
2
2
±1
140
100
100
1600
1500
50
1
12
30
60
40
150
18
18
40
40
40
6
V
μA
kΩ
μA
μA
Ω
Ω
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
Other Pin Functions
●
●
●
●
Propagation Delays
t
CB
t
PHL(SENSE)
t
PHH(AUXON)
t
PHH(12ON)
t
RST(ON)
t
RST(VCC)
t
PLL(UVLO)
●
●
●
●
●
●
●
●
●
●
●
●
●
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 device pins are positive; all currents out of
the device pins are negative. All voltages are referenced to GND unless
otherwise specified.
Note 3:
An internal clamp limits the 12V
GATE
pin to a minimum of 4.5V
above 12V
OUT
. Driving this pin to voltages beyond the clamp may damage
the device.
Note 4:
For the DFN package, the AUX switch on resistance, R
DS(ON)
limit
is guaranteed by correlation to wafer test measurements.
⎯ ⎯ ⎯ ⎯ ⎯ ⎯ ⎯ ⎯ ⎯ ⎯ ⎯ ⎯
⎯ ⎯ ⎯ ⎯ ⎯ ⎯ ⎯ ⎯
Note 5:
The output pins FAULT, 12PGOOD and AUXPGOOD have an internal
pull-up to V
CC
of 10μA. However, an external pull-up resistor may be used
