OMO ElectronicOMO Electronic
Expand menu
Hello, Sign inMy Account
0 Cart

LT1372CS8#PBF

P1-P3P4-P6P7-P9P10-P12
1
LT1372/LT1377
500kHz and 1MHz
High Efficiency
1.5A Switching Regulators
■
Boost Regulators
■
CCFL Backlight Driver
■
Laptop Computer Supplies
■
Multiple Output Flyback Supplies
■
Inverting Supplies
The LT
®
1372/LT1377 are monolithic high frequency
switching regulators. They can be operated in all standard
switching configurations including boost, buck, flyback,
forward, inverting and “Cuk.” A 1.5A high efficiency switch
is included on the die, along with all oscillator, control and
protection circuitry. All functions of the LT1372/LT1377
are integrated into 8-pin SO/PDIP packages.
The LT1372/LT1377 typically consumes only 4mA quies-
cent current and has higher efficiency than previous parts.
High frequency switching allows for very small inductors
to be used. All surface mount components consume less
than 0.5 square inch of board space.
New design techniques increase flexibility and maintain
ease of use. Switching is easily synchronized to an exter-
nal logic level source. A logic low on the shutdown pin
reduces supply current to 12µA. Unique error amplifier
circuitry can regulate positive or negative output voltage
while maintaining simple frequency compensation tech-
niques. Nonlinear error amplifier transconductance re-
duces output overshoot on start-up or overload recovery.
Oscillator frequency shifting protects external compo-
nents during overload conditions.
■
Faster Switching with Increased Efficiency
■
Uses Small Inductors: 4.7µH
■
All Surface Mount Components
■
Only 0.5 Square Inch of Board Space
■
Low Minimum Supply Voltage: 2.7V
■
Quiescent Current: 4mA Typ
■
Current Limited Power Switch: 1.5A
■
Regulates Positive or Negative Outputs
■
Shutdown Supply Current: 12µA Typ
■
Easy External Synchronization
■
8-Pin SO or PDIP Packages
, LTC and LT are registered trademarks of Linear Technology Corporation.
12V Output Efficiency
OUTPUT CURRENT (A)
0.01
50
EFFICIENCY (%)
60
70
80
90
0.1 1
LT1372 • TA02
100
V
IN
= 5V
5V-to-12V Boost Converter
LT1372/LT1377
V
IN
V
C
5V
1
2
8
5
4
6, 7
GND
FB
LT1372 • TA01
V
SW
S/S
L1*
4.7µH
C1**
22µF
C4**
22µF
C2
0.047µF
C3
0.0047µF
R3
2k
R2
6.19k
1%
R1
53.6k
1%
V
OUT
†
12V
D1
MBRS120T3
ON
OFF
*FOR LT1372 USE 10µH
COILCRAFT DO1608-472 (4.7µH) OR
COILCRAFT DT3316-103 (10µH) OR
SUMIDA CD43-4R7 (4.7µH) OR
SUMIDA CD73-100KC (10µH) OR
**AVX TPSD226M025R0200
L1
4.7µH
10µH
I
OUT
(LT1377)
0.25A
0.35A
I
OUT
(LT1372)
NA
0.29A
†
MAX I
OUT
+ +
FEATURES
DESCRIPTIO
U
APPLICATIO S
U
TYPICAL APPLICATIO
U
2
LT1372/LT1377
(Note 1)
Supply Voltage ....................................................... 30V
Switch Voltage
LT1372/LT1377 .................................................. 35V
LT1372HV .......................................................... 42V
S/S Pin Voltage....................................................... 30V
Feedback Pin Voltage (Transient, 10ms) .............. ±10V
Feedback Pin Current........................................... 10mA
Negative Feedback Pin Voltage
(Transient, 10ms)............................................. ±10V
Operating Junction Temperature Range
Commercial ........................................ 0°C to 125°C*
Industrial ......................................... –40°C to 125°C
Short Circuit ......................................... 0°C to 150°C
Storage Temperature Range ................ –65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
ORDER PART NUMBER
LT1372CN8
LT1372HVCN8
LT1372CS8
LT1372HVCS8
LT1372IN8
LT1372HVIN8
LT1372IS8
LT1372HVIS8
LT1377CS8
LT1377IS8
1
2
3
4
8
7
6
5
TOP VIEW
V
C
FB
NFB
S/S
V
SW
GND
GND S
V
IN
N8 PACKAGE
8-LEAD PDIP
S8 PACKAGE
8-LEAD PLASTIC SO
T
JMAX
= 125°C, θ
JA
= 100°C/ W (N8)
T
JMAX
= 125°C, θ
JA
= 120°C/ W (S8)
S8 PART MARKING
1372
1372I
1377
1377I
1372H
1372HI
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
REF
Reference Voltage Measured at Feedback Pin 1.230 1.245 1.260 V
V
C
= 0.8V ● 1.225 1.245 1.265 V
I
FB
Feedback Input Current V
FB
= V
REF
250 550 nA
● 900 nA
Reference Voltage Line Regulation 2.7V ≤ V
IN
≤ 25V, V
C
= 0.8V ● 0.01 0.03 %/V
V
NFB
Negative Feedback Reference Voltage Measured at Negative Feedback Pin –2.540 – 2.490 –2.440 V
Feedback Pin Open, V
C
= 0.8V ● –2.570 –2.490 –2.410 V
I
NFB
Negative Feedback Input Current V
NFB
= V
NFR
● –45 –30 –15 µA
Negative Feedback Reference Voltage 2.7V ≤ V
IN
≤ 25V, V
C
= 0.8V ● 0.01 0.05 %/V
Line Regulation
g
m
Error Amplifier Transconductance ∆I
C
= ±25µA 1100 1500 1900 µmho
● 700 2300 µmho
Error Amplifier Source Current V
FB
= V
REF
– 150mV, V
C
= 1.5V ● 120 200 350 µA
Error Amplifier Sink Current V
FB
= V
REF
+ 150mV, V
C
= 1.5V ● 1400 2400 µA
Error Amplifier Clamp Voltage High Clamp, V
FB
= 1V 1.70 1.95 2.30 V
Low Clamp, V
FB
= 1.5V 0.25 0.40 0.52 V
A
V
Error Amplifier Voltage Gain 500 V/V
V
C
Pin Threshold Duty Cycle = 0% 0.8 1 1.25 V
f Switching Frequency 2.7V ≤ V
IN
≤ 25V
LT1372 450 500 550 kHz
0°C ≤ T
J
≤ 125°C ● 430 500 580 kHz
–40°C ≤ T
J
< 0°C (I Grade) 400 580 kHz
LT1377 0.90 1 1.10 MHz
0°C ≤ T
J
≤ 125°C ● 0.86 1 1.16 MHz
–40°C ≤ T
J
< 0°C (I Grade) 0.80 1.16 MHz
The ● denotes specifcatons which appy over the full operating temperature range, otherwise specifications are at T
A
= 25°C.
V
IN
= 5V, V
C
= 0.6V, V
FB
= V
REF
, V
SW
, S/S and NFB pins open, unless otherwise noted.
Consult factory for parts specified with wider operating temperature ranges.
*Units shipped prior to Date Code 9552 are rated at 100°C maximum
operating temperature.
ABSOLUTE AXI U RATI GS
WWWU
PACKAGE/ORDER I FOR ATIO
UU
W
ELECTRICAL CHARACTERISTICS
3
LT1372/LT1377
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Maximum Switch Duty Cycle ● 85 95 %
Switch Current Limit Blanking Time 130 260 ns
BV Output Switch Breakdown Voltage LT1372/LT1377 ● 35 47 V
LT1372HV
0°C ≤ T
J
≤ 125°C ● 42 47 V
–40°C ≤ T
J
< 0°C (I Grade) 40 V
V
SAT
Output Switch “On” Resistance I
SW
= 1A ● 0.5 0.8 Ω
I
LIM
Switch Current Limit Duty Cycle = 50% ● 1.5 1.9 2.7 A
Duty Cycle = 80% (Note 2)
● 1.3 1.7 2.5 A
∆I
IN
Supply Current Increase During Switch On-Time 15 25 mA/A
∆I
SW
Control Voltage to Switch Current 2A/V
Transconductance
Minimum Input Voltage ● 2.4 2.7 V
I
Q
Supply Current 2.7V ≤ V
IN
≤ 25V ● 4 5.5 mA
Shutdown Supply Current 2.7V ≤ V
IN
≤ 25V, V
S/S
≤ 0.6V
0°C ≤ T
J
≤ 125°C ● 12 30 µA
–40°C ≤ T
J
< 0°C (I Grade) 50 µA
Shutdown Threshold 2.7V ≤ V
IN
≤ 25V ● 0.6 1.3 2 V
Shutdown Delay ● 51225µs
S/S Pin Input Current 0V ≤ V
S/S
≤ 5V ● –10 15 µA
Synchronization Frequency Range LT1372 ● 600 800 kHz
LT1377
● 1.2 1.6 MHz
Switch Saturation Voltage
vs Switch Current
TEMPERATURE (°C)
–50
1.8
INPUT VOLTAGE (V)
2.0
2.2
2.4
2.6
050
100
150
LT1372 • G03
2.8
3.0
–25 25
75
125
Minimum Input Voltage
vs Temperature
DUTY CYCLE (%)
0
SWITCH CURRENT LIMIT (A)
1.0
2.0
3.0
0.5
1.5
2.5
20 40 60 80
LT1372 • G02
10010
0
30 50 70 90
25°C AND
125°C
–55°C
Switch Current Limit
vs Duty Cycle
TYPICAL PERFORMANCE CHARACTERISTICS
U
W
SWITCH CURRENT (A)
0
SWITCH SATURATION VOLTAGE (V)
0.6
0.8
1.0
1.6
LT1372 • G01
0.4
0.2
0.5
0.7
0.9
0.3
0.1
0
0.4
0.8
1.2
2.0
1.4
0.2
0.6
1.0
1.8
100°C
150°C
25°C
–55°C
Note 1: Absolute Maximum Ratings are those values beyond which the life
of the device may be impaired.
The ● denotes specifcatons which appy over the full operating temperature range, otherwise specifications are at T
A
= 25°C.
V
IN
= 5V, V
C
= 0.6V, V
FB
= V
REF
, V
SW
, S/S and NFB pins open, unless otherwise noted.
ELECTRICAL CHARACTERISTICS
Note 2: For duty cycles (DC) between 50% and 90%, minimum
guaranteed switch current is given by I
LIM
= 0.667 (2.75 – DC).
P1-P3P4-P6P7-P9P10-P12

LT1372CS8#PBF

Mfr. #:
Buy LT1372CS8#PBF
Manufacturer:
Analog Devices / Linear Technology
Description:
Switching Voltage Regulators 500kHz & 1MHz Hi Eff 1.5A Sw Regs
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union

Products related to this Datasheet