1
dc1624af
DEMO MANUAL DC1624A
Description
LTC4225-1/LTC4225-2
Dual Ideal Diode and
Hot Swap Controller
Demonstration circuit 1624A contains two independent rail
circuits each with Hot Swap™ and ideal diode functionality
provided by the LTC4225-1/LTC4225-2 dual ideal diode
and Hot Swap controller.
DC1624A facilitates evaluation of LTC4225 performance in
different operation modes such as supply ramp-up, power
supply switchover, steady state, and overcurrent faults.
Power supply switchover mode can be realized as either
an ideal diode functionality or as a prioritizer functionality.
Each DC1624A rail circuit is assembled to operate with a
12V supply and 11.5A maximum current load.
The main components of the board are the LTC4225
controller, two MOSFETs operating as ideal diodes, two
MOSFETs operating as Hot Swap devices, two power sense
resistors, two jumpers for independently enabling each
perForMAnce sUMMArY
rail, four LEDs to indicate power good and fault conditions
separately for each channel, and input voltage snubbers.
There are pads for optional RC circuits for each Hot Swap
MOSFET gate in order to adjust output voltage slew rate.
The standard configuration (as DC1624A populated by
default) places the ideal diode MOSFET ahead of the
Hot Swap MOSFET. The board also has pads for an alter-
native configuration with the Hot Swap MOSFET located
ahead of the ideal diode MOSFET.
Design files for this circuit board are available at
http://www.linear.com/demo
(T
A
= 25°C)
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
V
IN
Input Supply Range
2.9
18
V
V
INTVCC(UVL)
Internal V
CC
Undervoltage Lockout
INTV
CC
Rising
2.1
2.2
2.3
V
V
INTVCC(HYST)
Internal V
CC
Undervoltage Lockout
Hysteresis
30
60
90
mV
Ideal Diode Control
ΔV
FWD(REG)
Forward Regulation Voltage (V
INN
- V
OUT
)
10
25
40
mV
ΔV
DGATE
External N-Channel Gate Drive
(V
DGATEN
- V
INN
)
ΔV
FWD
= 0.1V
IN < 7V
IN = 7V to 18V
5
10
7
12
14
14
V
V
I
CPO(UP)
CPO
N
Pull-Up Current
CPO = IN = 2.9V
CPO = IN = 18V
–60
–50
–95
–85
–120
–110
µA
µA
I
DGATE(FPU)
DGATE
N
Fast Pull-Up Current
ΔV
FWD
=0.2V, ΔV
DGATE
= 0V, CPO = 17V
–1.5
A
I
DGATE(FPD)
DGATE
N
Fast Pull-Down Current
ΔV
FWD
= –0.2V, ΔV
DGATE
= 5V
1.5
A
Hot Swap Control
ΔV
SENSE(CB)
Circuit Breaker Trip Sense Voltage
(V
INN
- V
ISENSEN
)
47.5
50
52.5
mV
ΔV
SENSE(ACL
)
Active Current Limit Sense Voltage
(V
INN
- V
ISENSEN
)
55
65
75
mV
L
, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
Downloaded from