LT4254
2
4254fb
Supply Voltage (V
CC
) .................................. –0.3 to 44V
SENSE, PWRGD ......................................... –0.3 to 44V
GATE .......................................................... –0.3 to 50V
FB, UV, OPEN ............................................. –0.3 to 44V
OV .............................................................. –0.3 to 18V
RETRY ........................................................ –0.3 to 15V
TIMER ..................................................... –0.3V to 4.3V
Maximum Input Current (TIMER) ....................... 100µA
Operating Temperature
LT4254C ................................................. 0°C to 70°C
LT4254I ............................................. –40°C to 85°C
Storage Temperature Range ................ –65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
ABSOLUTE AXI U RATI GS
W
WW
U
PACKAGE/ORDER I FOR ATIO
UUW
(Note 1)
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 24V unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
CC
Operating Voltage ● 10.8 36 V
I
CC
Operating Current 1.9 3 mA
UVLH
Undervoltage Threshold V
CC
Low-to-High Transition ● 3.96 4 4.04 V
V
UVHYS
Hysteresis 0.25 0.4 0.55 V
I
INUV
UV Input Current UV = 4.5V –0.1 –1 µA
UV = 0V –1.5 –3 µA
V
OVHL
Overvoltage Threshold V
CC
Low-to-High Transition ● 3.96 4 4.04 V
V
OVHYS
Hysteresis 0.25 0.4 0.55 V
I
INOV
OV Input Current 0V ≤ OV < 6.5V 0.1 1 µA
V
OPEN
Open-Circuit Voltage Threshold (V
CC
– V
SENSE
) ● 2 3.5 5 mV
V
OLOPEN
OPEN Output Low Voltage I
O
= 2mA 0.20 0.5 V
I
O
= 5mA 0.75 1.3 V
I
INOPEN
Leakage Current V
OPEN
= 5V 0.1 1 µA
V
SENSETRIP
SENSE Pin Trip Voltage (V
CC
– V
SENSE
) FB = 0V ● 5.5 12 25 mV
FB ≥ 2V
● 40 50 60 mV
I
INSNS
SENSE Pin Input Current 40 70 µA
I
PU
GATE Pull-Up Current Charge Pump On, ∆V
GATE
= 7V ● –15 –35 –63 µA
I
PD
GATE Pull-Down Current Any Fault, V
GATE
= 3V 40 60 80 mA
∆V
GATE
External N-Channel Gate Drive (Note 2) V
GATE
– V
CC
, 12V ≤ V
CC
≤ 20V ● 4.5 8.8 12.5 V
20V ≤ V
CC
≤ 36V ● 10 11 12.5 V
V
FB
FB Voltage Threshold FB High-to-Low Transition ● 3.96 4 4.04 V
FB Low-to-High Transition
● 4.20 4.45 4.65 V
V
FBHYS
FB Hysteresis Voltage 0.3 0.45 0.60 V
V
OLPGD
PWRGD Output Low Voltage I
O
= 1.6mA 0.25 0.4 V
I
O
= 5mA 0.63 1.0 V
ORDER PART NUMBER
GN PART MARKING
4254
4254I
LT4254CGN
LT4254IGN
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Note: NC = No Connect
Order Options Tape and Reel: Add #TR
Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF
Lead Free Part Marking: http://www.linear.com/leadfree/
GN PACKAGE
16-LEAD PLASTIC TSSOP
1
2
3
4
5
6
7
8
TOP VIEW
16
15
14
13
12
11
10
9
UV
OV
NC
OPEN
PWRGD
NC
RETRY
GND
V
CC
SENSE
NC
GATE
NC
NC
FB
TIMER
T
JMAX
= 125°C, θ
JA
= 130°C/W
