VC Voltage ................................................... –0.3V to 2V
SHDN
Voltage ............................................ –0.3V to 40V
SYNC Voltage............................................ –0.3V to 5.5V
Operating Junction Temperature Range
LT8580E (Notes 2, 5) ......................... –40°C to 125°C
LT8580I (Notes 2, 5).......................... –40°C to 125°C
LT8580H (Notes 2, 5) ........................ –40°C to 150°C
Storage Temperature Range ..................–65°C to 150°C
pin conFiguraTion
TOP VIEW
FBX 1
VC 2
V
IN
3
SW 4
9
GND
8 SYNC
7 SS
6 RT
5
SHDN
TOP VIEW
FBX
VC
V
IN
SW
1
2
3
4
9
GND
8
7
6
5
SYNC
SS
RT
SHDN
MS8E PACKAGE
8-LEAD PLASTIC MSOP
DD PACKAGE
8-LEAD (3mm
×
3mm) PLASTIC DFN
θ
JA
= 43°C/W
EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB
θ
JA
= 35°C/W TO 40°C/W
EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB
orDer inForMaTion
LEAD FREE FINISH
LT8580EDD#PBF
LT8580IDD#PBF
LT8580HDD#PBF
LT8580EMS8E#PBF
LT8580IMS8E#PBF
LT8580HMS8E#PBF
TAPE AND REEL
LT8580EDD#TRPBF
LT8580IDD#TRPBF
LT8580HDD#TRPBF
LT8580EMS8E#TRPBF
LT8580IMS8E#TRPBF
LT8580HMS8E#TRPBF
http://www.linear.com/product/LT8580#orderinfo
PART MARKING*
LGKH
LGKH
LGKH
LTGKJ
LTGKJ
LTGKJ
PACKAGE DESCRIPTION
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead (3mm
×
3mm) Plastic DFN
8-Lead Plastic MSOP
8-Lead Plastic MSOP
8-Lead Plastic MSOP
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.
Consult LTC Marketing for information on nonstandard 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/
2
8580fa
For more information
www.linear.com/LT8580
LT8580
elecTrical characTerisTics
PARAMETER
Operating Voltage Range
Positive Feedback Voltage
Negative Feedback Voltage
Positive FBX Pin Bias Current
Negative FBX Pin Bias Current
Error Amplifier Transconductance
Error Amplifier Voltage Gain
Quiescent Current
Quiescent Current in Shutdown
Reference Line Regulation
Switching Frequency, f
OSC
Switching Frequency in Foldback
Switching Frequency Set Range
SYNC High Level for Synchronization
SYNC Low Level for Synchronization
SYNC Clock Pulse Duty Cycle
Recommended Minimum SYNC Ratio f
SYNC
/f
OSC
Minimum Off-Time
Minimum On-Time
Switch Current Limit
Switch V
CESAT
Switch Leakage Current
Soft-Start Charging Current
SHDN
Minimum Input
Voltage High
SHDN
Input Voltage Low
SHDN
Pin Bias Current
SHDN
Hysteresis
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:
The LT8580E is guaranteed to meet performance specifications
from 0°C to 125°C junction temperature. Specifications over the –40°C
to 125°C operating junction temperature range are assured by design,
characterization and correlation with statistical process controls. The
LT8580I is guaranteed over the full –40°C to 125°C operating junction
temperature range. The LT8580H is guaranteed over the full –40°C to
150°C operating junction temperature range. Operating lifetime is derated
at junction temperatures greater than 125°C.
V
SHDN
= 2.5V, Not Switching
V
SHDN
= 0V
2.5V ≤ V
IN
≤ 40V
R
T
= 56.2k
R
T
= 422k
Compared to Normal f
OSC
SYNCing or Free Running
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 5V, V
SHDN
= V
IN
unless otherwise noted. (Note 2)
CONDITIONS
LT8580E, LT8580I
LT8580H
l
l
l
l
MIN
2.55
2.9
1.185
–3
81
81
TYP
MAX
40
40
1.220
12
85
86
UNITS
V
V
V
mV
µA
µA
µmhos
V/V
mA
µA
%/V
MHz
kHz
Ratio
kHz
V
V
%
ns
ns
A
A
A
mV
µA
µA
V
V
V
µA
µA
µA
mV
V
FBX
= Positive Feedback Voltage, Current Into Pin
V
FBX
= Negative Feedback Voltage, Current Out of Pin
l
l
1.204
3
83.3
83.3
200
60
1.2
0
0.01
1.5
200
1/6
l
l
1.23
165
200
1.3
35
1.7
1
0.05
1.77
235
1500
0.4
65
l
l
l
V
SYNC
= 0V to 2V
Minimum Duty Cycle (Note 3)
Maximum Duty Cycle (Notes 3, 4), f
OSC
= 1.5MHz
Maximum Duty Cycle (Notes 3, 4), f
OSC
= 200kHz
I
SW
= 0.75A
V
SW
= 5V
V
SS
= 0.5V
Active Mode,
SHDN
Rising
Active Mode,
SHDN
Falling
Shutdown Mode
V
SHDN
= 3V
V
SHDN
= 1.3V
V
SHDN
= 0V
l
l
l
1.2
0.6
0.4
l
l
l
l
4
1.23
1.21
3/4
100
120
1.5
1
0.8
400
0.01
6
1.31
1.27
44
12
0
40
1.8
1.5
1.4
1
8
1.4
1.33
0.3
56
15
0.1
9
Note 3:
Current limit guaranteed by design and/or correlation to static test.
Note 4:
Current limit measured at equivalent of listed switching frequency.
Note 5:
This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed 150°C when overtemperature protection is active.
Continuous operation above the specified maximum operating junction