(Note 2) .............................................–40°C to 125°C
Operating Junction Temperature
(Note 2) .............................................–40°C to 125°C
Storage Temperature Range...................–65°C to 150°C
16 15 14 13
NC 1
APD 2
MONIN 3
V
OUT
4
UD PACKAGE
16-LEAD (3mm 3mm) PLASTIC QFN
T
JMAX
= 125°C,
θ
JA
= 68°C/W,
θ
JC
= 4.2°C/W (NOTE 2)
EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
LEAD FREE FINISH
LT3571EUD#PBF
LT3571IUD#PBF
TAPE AND REEL
LT3571EUD#TRPBF
LT3571IUD#TRPBF
PART MARKING*
LDTN
LDTN
PACKAGE DESCRIPTION
16-Lead (3mm
×
3mm) Plastic QFN
16-Lead (3mm
×
3mm) Plastic QFN
TEMPERATURE RANGE
–40°C to 125°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/
ELECTRICAL CHARACTERISTICS
PARAMETER
Minimum Operating Voltage
Maximum Operating Voltage
Supply Current
Feedback Voltage
Feedback Line Regulation
Current Sense Voltage (V
OUT
– V
MONIN
)
FB Pin Bias Current
V
REF
Pin Voltage
V
REF
Pin Line Regulation
R
T
Voltage
SYNC Resistance to GND
SYNC Input Low
SYNC Input High
V
SYNC
= 2V
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C, V
IN
= 3V, V
SHDN
= 3V, unless otherwise noted.
CONDITIONS
MIN
TYP
MAX
2.7
20
V
FB
= 1.3V, Not Switching
V
SHDN
= 0V
V
CTRL
= 1.25V, V
OUT
= V
MONIN
2.7V < V
IN
< 20V
V
OUT
= 30V
V
FB
= 0V
I
REF
= –100μA
2.7V < V
IN
< 20V
l
l
l
l
UNITS
V
V
mA
μA
V
V
%/V
mV
nA
V
%V
V
kΩ
1.7
0.1
0.985
0.97
185
1.200
1
0.03
200
60
1.222
0.03
1
45
2.2
0.5
1.015
1.03
0.07
215
100
1.240
0.07
0.4
1.5
V
V
3571fa
2
LT3571
ELECTRICAL CHARACTERISTICS
PARAMETER
Switching Frequency
R
T
= 12.1k
R
T
= 4.22k
R
T
= 56.2k
R
T
= 56.2k (250kHz)
SYNC = 300kHz Clock Signal, R
T
= 56.2k
R
T
= 12.1k (1MHz)
R
T
= 4.22k (2MHz)
I
SW
= 200mA
V
SW
= 75V
I
SCHOTTKY
= 200mA
V
OUT
– V
SW
= 75V
1.5
0.4
50
V
CTRL
= 0.5V
Current Out of Pin, V
CTRL
= 0.5V
250nA ≤ I
APD
< 10μA, 10V < V
MONIN
< 75V
10μA ≤ I
APD
≤ 2.5mA, 20V < V
MONIN
< 75V
V
MONIN
– V
APD,
I
APD
= 1mA
V
MONIN
= 40V, V
APD
= 0V
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
IN
= 3V, V
SHDN
= 3V, unless otherwise noted.
CONDITIONS
l
MIN
0.85
1.7
210
95
92
85
75
370
TYP
1
2
250
97
96
90
80
470
240
MAX
1.15
2.3
280
UNITS
MHz
MHz
kHz
%
%
%
%
Maximum Duty Cycle
l
Switch Current Limit
Switch V
CESAT
Switch Leakage Current
Schottky Forward Voltage
Schottky Reverse Leakage
SHDN
Voltage High
SHDN
Voltage Low
SHDN
Pin Bias Current
CTRL to FB Offset
CTRL Input Bias Current
APD Current Monitor Gain
Monitor Output Voltage Clamp
APD Monitor Voltage Drop
MONIN Pin Current Limit
570
2
mA
mV
μA
mV
μA
V
V
μA
mV
mV
nA
850
5
65
15
20
100
0.215
0.206
–5
–10
0.185
0.194
4.8
5
5
20
0.20
0.20
11.5
5
30
V
5.2
V
mA
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 LT3571E is guaranteed to meet specified performance 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
LT3571I is guaranteed to meet performance specifications over the –40°C