900,000+ datasheet pdf search and download

Datasheet4U offers most rated semiconductors data sheet pdf




Linear Technology Electronic Components Datasheet

LT1576-5 Datasheet

1.5A/ 200kHz Step-Down Switching Regulator

No Preview Available !

FEATURES
s Constant 200kHz Switching Frequency
s 1.21V Reference Voltage
s Fixed 5V Output Option
s Easily Synchronizable
s Uses All Surface Mount Components
s Inductor Size Reduced to 15µH
s Saturating Switch Design: 0.2
s Effective Supply Current: 1.16mA
s Shutdown Current: 20µA
s Cycle-by-Cycle Current Limiting
s Fused Lead SO-8 Package
U
APPLICATIO S
s Portable Computers
s Battery-Powered Systems
s Battery Charger
s Distributed Power
LT1576/LT1576-5
1.5A, 200kHz Step-Down
Switching Regulator
DESCRIPTIO
The LT®1576 is a 200kHz monolithic buck mode switching
regulator. A 1.5A switch is included on the die along with
all the necessary oscillator, control and logic circuitry. The
topology is current mode for fast transient response and
good loop stability. The LT1576 is a modified version of the
industry standard LT1376 optimized for noise sensitive
applications.
In addition, the reference voltage has been lowered to
allow the device to produce output voltages down to 1.2V.
Quiescent current has been reduced by a factor of two.
Switch on resistance has been reduced by 30%. Switch tran-
sition times have been slowed to reduce EMI generation.
The oscillator frequency has been reduced to 200kHz to
maintain high efficiency over a wide output current range.
The pinout has been changed to improve PC layout by
allowing the high current high frequency switching cir-
cuitry to be easily isolated from low current noise sensitive
control circuitry. The new SO-8 package includes a fused
ground lead which significantly reduces the thermal resis-
tance of the device to extend the ambient operating tem-
perature range. There is an optional function of shutdown
or synchronization. Standard surface mount external parts
can be used including the inductor and capacitors.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATION
5V Buck Converter
INPUT
6V TO 25V C3* +
10µF TO
50µF
C2
0.33µF
VIN BOOST
VSW
LT1576 BIAS
L1**
15µH
D2
1N914
OUTPUT**
5V, 1.25A
OPEN = ON
SHDN
GND
* RIPPLE CURRENT RATING IOUT/2
** INCREASE L1 TO 30µH FOR LOAD
CURRENTS ABOVE 0.6A AND TO
60µH ABOVE 1A
SEE APPLICATIONS INFORMATION
FB
VC
CC
100pF
D1
1N5818
R1
15.8k
R2 +
4.99k
C1
100µF, 10V
SOLID
TANTALUM
1576 TA01
Efficiency vs Load Current
100
VOUT = 5V
95
VIN = 10V
L = 33µH
90
85
80
75
70
0
0.25 0.50 0.75 1.00
LOAD CURRENT (A)
1.25 1.50
1576 TA02
1


Linear Technology Electronic Components Datasheet

LT1576-5 Datasheet

1.5A/ 200kHz Step-Down Switching Regulator

No Preview Available !

LT1576/LT1576-5
ABSOLUTE MAXIMUM RATINGS
(Note 1)
Input Voltage .......................................................... 25V
BOOST Pin Above Input Voltage ............................. 10V
SHDN Pin Voltage ..................................................... 7V
BIAS Pin Voltage ...................................................... 7V
FB Pin Voltage (Adjustable Part) ............................ 3.5V
FB Pin Current (Adjustable Part) ............................ 1mA
SYNC Pin Voltage ..................................................... 7V
Operating Junction Temperature Range
LT1576C ............................................... 0°C to 125° C
LT1576I ........................................... – 40°C to 125°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
PACKAGE/ORDER INFORMATION
ORDER PART NUMBER
VSW 1
VIN 2
BOOST 3
GND 4
TOP VIEW
8
SHDN OR
SYNC*
7 FB OR SENSE*
6 VC
5 BIAS
S8 PACKAGE
8-LEAD PLASTIC SO
θJA = 80°C/ W WITH FUSED GROUND PIN
CONNECTED TO GROUND PLANE OR
LARGE LANDS
LT1576CS8
LT1576CS8-SYNC
LT1576IS8
LT1576IS8-SYNC
LT1576CS8-5
LT1576CS8-5 SYNC
LT1576IS8-5
LT1576IS8-5 SYNC
S8 PART MARKING
1576
1576SN
1576I
576ISN
15765
5765SN
1576I5
76I5SN
*Default is the adjustable output voltage device with FB pin and shutdown
function. Option -5 replaces FB with SENSE pin for fixed 5V output
applications. -SYNC replaces SHDN with SYNC pin for applications
requiring synchronization. Consult factory for Military grade parts.
ELECTRICAL CHARACTERISTICS The q denotes specifications which apply over the full operating temperature
range, otherwise specifications are TA, TJ = 25°C, VIN = 15V, VC = 1.5V, Boost = VIN + 5V, switch open, unless otherwise noted.
PARAMETER
CONDITIONS
MIN TYP MAX
UNITS
Feedback Voltage
All Conditions
1.195 1.21 1.225
q 1.18
1.24
V
V
Sense Voltage (Fixed 5V)
All Conditions
4.94 5.0 5.06
q 4.90
5.10
V
V
SENSE Pin Resistance
13 18.5 26
k
Reference Voltage Line Regulation
Feedback Input Bias Current
5V VIN 25V
0.01 0.03
%/V
q
0.5 2
µA
Error Amplifier Voltage Gain
(Notes 2, 8)
200 400
Error Amplifier Transconductance
I (VC) = ±10µA (Note 8)
800 1050 1300
q 400
1700
µMho
µMho
VC Pin to Switch Current Transconductance
Error Amplifier Source Current
Error Amplifier Sink Current
VC Pin Switching Threshold
VC Pin High Clamp
Switch Current Limit
Slope Compensation (Note 9)
VFB = 1.1V
VFB = 1.4V
Duty Cycle = 0
VC Open, VFB = 1.1V, DC 50%
DC = 80%
1.5
q 40 110 190
q 50 130 200
0.8
2.1
q 1.5 2 3.50
0.3
A/ V
µA
µA
V
V
A
A
Switch On Resistance (Note 7)
ISW = 1.5A
0.2 0.35
q 0.45
Maximum Switch Duty Cycle
VFB = 1.1V
90 94
q 86 94
%
%
2


Part Number LT1576-5
Description 1.5A/ 200kHz Step-Down Switching Regulator
Maker Linear Technology
PDF Download

LT1576-5 Datasheet PDF






Similar Datasheet

1 LT1576-5 1.5A/ 200kHz Step-Down Switching Regulator
Linear Technology





Part Number Start With

0    1    2    3    4    5    6    7    8    9    A    B    C    D    E    F    G    H    I    J    K    L    M    N    O    P    Q    R    S    T    U    V    W    X    Y    Z

Site map

Webmaste! click here

Contact us

Buy Components

Privacy Policy