|
|
PDF AFL270XXS Data sheet ( Hoja de datos )
| Número de pieza | AFL270XXS | |
| Descripción | ADVANCED ANALOG HIGH RELIABILITY HYBRID DC/DC CONVERTERS | |
| Fabricantes | International Rectifier | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de AFL270XXS (archivo pdf) en la parte inferior de esta página. Total 16 Páginas | ||
|
No Preview Available !
www.DataSheet4U.com
PD - 94435A
ADVANCED ANALOG
HIGH RELIABILITY
HYBRID DC/DC CONVERTERS
AFL270XXS SERIES
270V Input, Single Output
Description
The AFL Series of DC/DC converters feature high power
density with no derating over the full military tempera-
ture range. This series is offered as part of a complete
family of converters providing single and dual output
voltages and operating from nominal +28 or +270 volt
inputs with output power ranging from 80 to 120 watts.
For applications requiring higher output power, multiple
converters can be operated in parallel. The internal cur-
rent sharing circuits assure equal current distribution
among the paralleled converters. This series incorpo-
rates Advanced Analog’s proprietary magnetic pulse
feedback technology providing optimum dynamic line
and load regulation response. This feedback system
samples the output voltage at the pulse width modulator
fixed clock frequency, nominally 550 KHz. Multiple con-
verters can be synchronized to a system clock in the
500 KHz to 700 KHz range or to the synchronization
output of one converter. Undervoltage lockout, primary
and secondary referenced inhibit, soft-start and load
fault protection are provided on all models.
These converters are hermetically packaged in two en-
closure variations, utilizing copper core pins to mini-
mize resistive DC losses. Three lead styles are avail-
able, each fabricated with Advanced Analog’s rugged
ceramic lead-to-package seal assuring long term
hermeticity in the most harsh environments.
Manufactured in a facility fully qualified to MIL-PRF-
38534, these converters are available in four screening
grades to satisfy a wide range of requirements. The CH
grade is fully compliant to the requirements of MIL-PRF-
38534 for class H. The HB grade is fully processed and
screened to the class H requirement, but does not have
material element evaluated to the class H requirement.
Both grades are tested to meet the complete group “A”
test specification over the full military temperature range
without output power deration. Two grades with more
limited screening are also available for use in less
AFL
Features
n 160 To 400 Volt Input Range
n 5, 6, 9, 12, 15 and 28 Volt Outputs Available
n High Power Density - up to 84 W /in3
n Up To 120 Watt Output Power
n Parallel Operation with Stress and Current
Sharing
n Low Profile (0.380") Seam Welded Package
n Ceramic Feedthru Copper Core Pins
n High Efficiency - to 87%
n Full Military Temperature Range
n Continuous Short Circuit and Overload
Protection
n Remote Sensing Terminals
n Primary and Secondary Referenced
Inhibit Functions
n Line Rejection > 60 dB - DC to 50KHz
n External Synchronization Port
n Fault Tolerant Design
n Dual Output Versions Available
n Standard Military Drawings Available
demanding applications. Variations in electrical,
mechanical and screening can be accommo-
dated. Contact Advanced Analog for special re-
quirements.
www.irf.com
1
07/24/02
1 page  
DC INPUT 1
INPUT
FILTER
AFL270XXS Circuit Description
Figure I. AFL Single Output Block Diagram
AFL270XXS Series
ENABLE 1 4
SYNC OUTPUT 5
SYNC INPUT 6
CASE 3
INPUT RETURN 2
PRIMARY
BIAS SUPPLY
CONTROL
.*
OUTPUT
FILTER
ERROR
AMP
& REF
CURRENT
SENSE
SHARE
AMPLIFIER
SENSE
AMPLIFIER
7 + OUTPUT
10 + SENSE
11 SHARE
12 ENABLE 2
9 - SENSE
8 OUTPUT RETURN
Circuit Operation and Application Information
The AFL series of converters employ a forward switched
mode converter topology. (refer to Figure I.) Operation of
the device is initiated when a DC voltage whose magnitude
is within the specified input limits is applied between pins 1
and 2. If pin 4 is enabled (at a logical 1 or open) the primary
bias supply will begin generating a regulated housekeeping
voltage bringing the circuitry on the primary side of the con-
verter to life. Two power MOSFETs used to chop the DC
input voltage into a high frequency square wave, apply this
chopped voltage to the power transformer. As this switch-
ing is initiated, a voltage is impressed on a second winding
of the power transformer which is then rectified and applied
to the primary bias supply. When this occurs, the input
voltage is shut out and the primary bias voltage becomes
exclusively internally generated.
The switched voltage impressed on the secondary output
transformer winding is rectified and filtered to provide the
converter output voltage. An error amplifier on the second-
ary side compares the output voltage to a precision refer-
ence and generates an error signal proportional to the dif-
ference. This error signal is magnetically coupled through
the feedback transformer into the controller section of the
converter varying the pulse width of the square wave sig-
nal driving the MOSFETs, narrowing the width if the output
voltage is too high and widening it if it is too low.
used, the sense leads should be connected to their respec-
tive output terminals at the converter. Figure III. illustrates a
typical application.
Inhibiting Converter Output
As an alternative to application and removal of the DC
voltage to the input, the user can control the converter
output by providing TTL compatible, positive logic signals
to either of two enable pins (pin 4 or 12). The distinction
between these two signal ports is that enable 1 (pin 4) is
referenced to the input return (pin 2) while enable 2 (pin 12)
is referenced to the output return (pin 8). Thus, the user
has access to an inhibit function on either side of the isola-
tion barrier. Each port is internally pulled “high” so that
when not used, an open connection on both enable pins
permits normal converter operation. When their use is
desired, a logical “low” on either port will shut the con-
verter down.
Figure II. Enable Input Equivalent Circuit
Pin 4 or
Pin 12
1N4148
100K
290K
+5.6V
Disable
Remote Sensing
Connection of the + and - sense leads at a remotely locat-
led load permits compensation for resistive voltage drop
between the converter output and the load when they are
physically separated by a significant distance. This con-
nection allows regulation to the placard voltage at the point
of application. When the remote sensing features is not
Pin 2 or
Pin 8
2N3904
150K
www.irf.com
5
5 Page 
AFL270XXS Series
Typical Performance Characteristics - AFL27005S
Output Load = 100%, Vin = 270VDC unless otherwise specified.
Turn-on Time, No Load
6
6
55
44
33
22
11
00
-1
70 75 80 85 90 95 100
Time from Application of Input Power ( msec )
Output Ripple Voltage
8
-1
70
40
Turn-on Time, Full Load
75 80 85 90 95
Time from Application of Input Power ( msec )
Input Ripple Current
100
4 20
00
-4 -20
-8
0 2 4 6 8 10
Time ( usec )
Output Load Transient Response
50% Load to/from 100% Load
400
-40
0 2 4 6 8 10
Time ( usec )
Output Load Transient Response
10% Load to/from 50% Load
400
200 200
00
-200
-400
0
200 400 600 800 1000
Time ( usec )
www.irf.com
-200
-400
0
200 400 600 800 1000
Time ( usec )
11
11 Page | ||
| Páginas | Total 16 Páginas | |
| PDF Descargar | [ Datasheet AFL270XXS.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| AFL270XXD | ADVANCED ANALOG HIGH RELIABILITY HYBRID DC/DC CONVERTERS | International Rectifier |
| AFL270XXS | ADVANCED ANALOG HIGH RELIABILITY HYBRID DC/DC CONVERTERS | International Rectifier |
| 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 |