|
|
PDF LT1171 Data sheet ( Hoja de datos )
| Número de pieza | LT1171 | |
| Descripción | 100kHz/ 5A/ 2.5A and 1.25A High Efficiency Switching Regulators | |
| Fabricantes | Linear Technology | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de LT1171 (archivo pdf) en la parte inferior de esta página. Total 20 Páginas | ||
|
No Preview Available !
LT1170/LT1171/LT1172
100kHz, 5A, 2.5A and 1.25A
High Efficiency Switching Regulators
FEATURES
DESCRIPTIO
s Wide Input Voltage Range: 3V to 60V
s Low Quiescent Current: 6mA
s Internal 5A Switch (2.5A for LT1171,
1.25A for LT1172)
s Shutdown Mode Draws Only 50µA Supply Current
s Very Few External Parts Required
s Self-Protected Against Overloads
s Operates in Nearly All Switching Topologies
s Flyback-Regulated Mode Has Fully Floating Outputs
s Comes in Standard 5-Pin Packages
s LT1172 Available in 8-Pin MiniDIP and Surface Mount
Packages
s Can Be Externally Synchronized
U
APPLICATIO S
s Logic Supply 5V at 10A
s 5V Logic to ±15V Op Amp Supply
s Battery Upconverter
s Power Inverter (+ to –) or (– to +)
s Fully Floating Multiple Outputs
USER NOTE:
This data sheet is only intended to provide specifications, graphs, and a general functional description
of the LT1170/LT1171/LT1172. Application circuits are included to show the capability of the
LT1170/LT1171/LT1172. A complete design manual (AN19) should be obtained to assist in
developing new designs. This manual contains a comprehensive discussion of both the LT1070 and
the external components used with it, as well as complete formulas for calculating the values of these
components. The manual can also be used for the LT1170/LT1171/LT1172 by factoring in the higher
frequency. A CAD design program called SwitcherCADTM is also available.
The LT®1170/LT1171/LT1172 are monolithic high power
switching regulators. They can be operated in all standard
switching configurations including buck, boost, flyback,
forward, inverting and “Cuk.” A high current, high effi-
ciency switch is included on the die along with all oscilla-
tor, control and protection circuitry. Integration of all
functions allows the LT1170/LT1171/LT1172 to be built in
a standard 5-pin TO-3 or TO-220 power package as well as
the 8-pin packages (LT1172). This makes them extremely
easy to use and provides “bust proof” operation similar to
that obtained with 3-pin linear regulators.
The LT1170/LT1171/LT1172 operate with supply volt-
ages from 3V to 60V, and draw only 6mA quiescent
current. They can deliver load power up to 100W with no
external power devices. By utilizing current-mode switch-
ing techniques, they provide excellent AC and DC load and
line regulation.
The LT1170/LT1171/LT1172 have many unique features
not found even on the vastly more difficult to use low
power control chips presently available. They use adaptive
antisat switch drive to allow very wide ranging load cur-
rents with no loss in efficiency. An externally activated
shutdown mode reduces total supply current to 50µA
typically for standby operation.
, LTC and LT are registered trademarks of Linear Technology Corporation.
SwitcherCAD is a trademark of Linear Technology Corporation.
TYPICAL APPLICATIO
Boost Converter (5V to 12V)
5V L1**
50µH
L2 OUTPUT
10µH FILTER
+
C3*
100µF
VIN
VSW
LT1170
FB
GND VC
R3
1k
C1
1µF
D1
MBR330
C3
100µF
+
C2
1000µF
12V
R1 1A
10.7k
1%
R2
1.24k
1%
*REQUIRED IF INPUT LEADS ≥ 2" ** COILTRONICS 50-2-52
PULSE ENGINEERING 92114
1170/1/2 TA01
Maximum Output Power*
100
LT1170
80
60
BOOST
40
BUCK-BOOST
VO = 30V
FLYBACK
* ROUGH GUIDE ONLY. BUCK MODE
POUT = (5A)(VOUT)
SPECIAL TOPOLOGIES DELIVER
MORE POWER.
** DIVIDE VERTICAL POWER SCALE
BY TWO FOR LT1171, BY FOUR
FOR LT1172.
LT1170/1/2 TA02
20
BUCK-BOOST
VO = 5V
0
0 10 20 30 40 50
INPUT VOLTAGE (V)
1
1 page  
LT1170/LT1171/LT1172
TYPICAL PERFOR A CE CHARACTERISTICS
Line Regulation
5
4
3 TJ = 150°C
2
1
0 TJ = –55°C
–1
TJ = 25°C
–2
–3
–4
–5
0
10 20 30 40
INPUT VOLTAGE (V)
50 60
1170/1/2 G04
Supply Current vs Supply Voltage
(Shutdown Mode)
160
TJ = 25°C
140
120
100
80 VC = 50mV
60
40
20
0
0
VC = 0V
10 20 30 40
SUPPLY VOLTAGE (V)
50 60
1170/1/2 G07
Shutdown Mode Supply Current
200
180
160
140
120 TJ = 150°C
100
80
60
–55°C ≤ TJ ≤ 125°C
40
20
0
0 10 20 30 40 50 60 70 80 90 100
VC PIN VOLTAGE (mV)
1170/1/2 G10
Reference Voltage vs Temperature
1.250
1.248
1.246
1.244
1.242
1.240
1.238
1.236
1.234
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
1170/1/2 G05
Feedback Bias Current vs
Temperature
800
700
600
500
400
300
200
100
0
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
1170/1/2 G06
Driver Current* vs Switch Current
160
140
120
100
TJ = – 55°C
80
60
TJ = ≥ 25°C
40
20
0
01 2345
SWITCH CURRENT (A)
1170/1/2 G08
* AVERAGE LT1170 POWER SUPPLY CURRENT IS
FOUND BY MULTIPLYING DRIVER CURRENT BY
DUTY CYCLE, THEN ADDING QUIESCENT CURRENT.
Supply Current vs Input Voltage*
15
14 TJ = 25°C
13 NOTE THAT THIS CURRENT DOES NOT
INCLUDE DRIVER CURRENT, WHICH IS
12 A FUNCTION OF LOAD CURRENT AND
DUTY CYCLE.
11
10 90% DUTY CYCLE
9 50% DUTY CYCLE
8
7 10% DUTY CYCLE
6 0% DUTY CYCLE
5
0 10 20 30 40 50 60
INPUT VOLTAGE (V)
1170/1/2 G09
* UNDER VERY LOW OUTPUT CURRENT CONDITIONS,
DUTY CYCLE FOR MOST CIRCUITS WILL APPROACH
10% OR LESS.
Error Amplifier Transconductance
5000
4500
4000
gm
=
∆I
∆V
(VC
(FB
PIN)
PIN)
3500
3000
2500
2000
1500
1000
500
0
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
1170/1/2 G11
VC Pin Characteristics
300
200 VFB = 1.5V (CURRENT INTO VC PIN)
100
0
–100
TJ = 25°C
–200
–300
VFB = 0.8V (CURRENT OUT OF VC PIN)
–400
0
0.5 1.0 1.5 2.0 2.5
VC PIN VOLTAGE (V)
1170/1/2 G12
5
5 Page 
LT1170/LT1171/LT1172
TYPICAL APPLICATIO S (Note that maximum output currents are divided by 2 for LT1171, by 4 for LT1172.)
Driving High Voltage FET
(for Off-Line Applications, See AN25)
10V TO
20V
+
VIN
VSW
LT1170
G
D
Q1
D1
GND
1170/1/2 TA05
Negative-to-Positive Buck-Boost Converter†
External Current Limit
VX
R2
R1
500Ω
≈ 2V
D1
LT1170
GND VC
1170/1/2 TA06
External Current Limit
L1**
50µH
L2
OPTIONAL
OUTPUT
FILTER
C3
+
C4*
100µF
OPTIONAL
INPUT FILTER
L3
VIN
VSW
LT1170
FB
GND VC
R3
2.2k
D1
+
C2
1000µF
VOUT
12V
R1 2A
11.3k
Q1
R2
1.24k
VIN
–20V
C1
0.22µF
* REQUIRED IF INPUT LEADS ≥ 2"
** PULSE ENGINEERING 92114, COILTRONICS 50-2-52
† THIS CIRCUIT IS OFTEN USED TO CONVERT –48V TO 5V. TO GUARANTEE
FULL SHORT-CIRCUIT PROTECTION, THE CURRENT LIMIT CIRCUIT SHOWN
IN AN19, FIGURE 39, SHOULD BE ADDED WITH C1 REDUCED TO 200pF.
1170/1/2 TA07
Negative Buck Converter
VIN
VSW
+
– VIN
LT1170
FB
GND VC
R1
1k
Q1
C1
1000pF
RS
NOTE THAT THE LT1170
GND PIN IS NO LONGER
COMMON TO VIN–.
R2
C2
1170/1/2 TA08
* REQUIRED IF INPUT LEADS ≥ 2"
** PULSE ENGINEERING 92114
COILTRONICS 50-2-52
+
C3*
100µF
OPTIONAL
INPUT FILTER
L3
VIN
–20V
VIN
VSW
LT1170
FB
GND VC
C1
R3
D1
L1**
50µH
+
C2
1000µF
R1
4.64k
Q1
2N3906
R4
12k
LOAD
–5.2V
4.5A
R2
1.24k
OPTIONAL
OUTPUT
FILTER
+
C4
200µF
L2
4µH
1170/1/2 TA09
11
11 Page | ||
| Páginas | Total 20 Páginas | |
| PDF Descargar | [ Datasheet LT1171.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| LT117 | Positive Adjustable Regulator | Linear Technology |
| LT1170 | 100kHz/ 5A/ 2.5A and 1.25A High Efficiency Switching Regulators | Linear Technology |
| LT1171 | 100kHz/ 5A/ 2.5A and 1.25A High Efficiency Switching Regulators | Linear Technology |
| LT1172 | 100kHz/ 5A/ 2.5A and 1.25A High Efficiency Switching Regulators | Linear Technology |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |