|
|
PDF AN957 Data sheet ( Hoja de datos )
| Número de pieza | AN957 | |
| Descripción | Measuring HEXFETCharacteristics | |
| Fabricantes | ETC | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de AN957 (archivo pdf) en la parte inferior de esta página. Total 13 Páginas | ||
|
No Preview Available !
Index
Topics covered:
Measuring HEXFET®Characteristics
(HEXFET is the trademark for International Rectifier Power MOSFETs)
• Converting the nomenclature from bipolars to MOSFETs
• P-Channel HEXFET Power MOSFETs
• Initial settings
• Breakdown
• Drain leakage
• Gate threshold
• Gate leakage
• Transconductance
• On-resistance
• Diode drop
• Characteristics in synchronous rectification
• Transfer characteristics
• Measurements without a curve tracer
• Device capacitances
• Switching times
• Gate charge
• Reverse recovery
• A fixture to speed-up testing time
• Related topics
AN-957 (v.Int)
1. General
Curve tracers have generally been designed for making measurements on bipolar transistors. While power MOSFETs can be
tested satisfactorily on most curve tracers, the controls of these instruments are generally labeled with reference to bipolar
transistors, and the procedure to follow in the case of MOSFETs is not immediately obvious. This application note describes
methods for measuring HEXFET Power MOSFET characteristics, both with a curve tracer and with special-purpose test circuits.
Testing HEXFET Power MOSFETs on a curve tracer is a simple matter, provided the broad correspondence between bipolar
transistor and HEXFET Power MOSFET features are borne in mind. Table 1 matches some features of HEXFET Power
MOSFETs with their bipolar counterparts. The HEXFET Power MOSFET used in all the examples is the IRF630. The control
settings given in the examples are those suitable for the IRF630. The user must modify these values appropriately when testing a
different device. The IRF630 was selected since it is a typical mid-range device with a voltage rating of 200 volts and a
continuous current rating of 9 amps (with TC = 25°C). For measurements with currents above 20 amps, or for pulsed tests not
controlled by the gate, the Tektronix 176 Pulsed High
Current Fixture must be used instead of the standard test fixture.
The IRF630 is an N-channel device. For a P-channel device, all the test procedures are the same except that the position of the
Polarity Selector Switch must be reversed—that is, for P-channel devices, it must be in the PNP position.
The curve tracer used as an example in this application note is a Tektronix 576, since this instrument is in widespread use.
However, the principles involved apply equally well to other makes and models. Figure 1 shows the layout of the controls of the
Tektronix 576 curve tracer, with major controls identified by the names used in this application note. Throughout this application
note, when controls are referred to, the name of the control is printed in capitals. For all tests, when the power is on, the initial
state of the curve tracer is assumed to be as follows:
• LEFT/ RIGHT switch in “off” position
• VARIABLE COLLECTOR SUPPLY at zero
• DISPLAY not inverted
• DISPLAY OFFSET set at zero
• STEP/OFFSET POLARITY button OUT (not inverted)
• VERT/HORIZ DISPLAY MAGNIFIER set at NORM (OFF)
• The REP button of the STEP FAMILY selector should be IN
• The AID button of the OFFSET selector should be IN
To Order
1 page  
Index
AN-957 (v.Int)
7. RDS(on)
This is the drain-source resistance at 25°C with VGS = 10V. Since RDS(on) is temperature-dependent, it is important to minimize
heating of the junction during the test. A pulse test is therefore used to measure this parameter. The test is set up in the following
manner:
1. Connect the device as follows: gate to “B”, drain to “C”, source to “E”.
2. Set the MAX PEAK VOLTS to 15 V.
3. Set the SERIES RESISTOR to 0.3 Ohms.
4. The POLARITY switch should be set to NPN.
5. The MODE switch should be set to “NORM”.
6. Set the STEP AMPLITUDE to 1V.
7. Set NUMBER OF STEPS to 10.
8. Set OFFSET MULT to 0.
9. The CURRENT LIMIT should be set to 500 mA.
10.The STEP MULTIPLIER button should be OUT—that is, 0.1X not
selected.
11.On the PULSED STEPS selector, the 80 microsec button should be IN
(or the 300 microsec, if the 80 is not available).
12.On the RATE selector, the 0.5X button should be IN.
13.Set VERTICAL CURRENT/DIV at 1 amp/div (IRF630). This scale
should be chosen according to the on-resistance of the device being
tested
14.Set the CONNECTION SELECTOR to the “STEP GEN” position in
the “EMITTER GROUNDED” sector.
15.Connect the device using the LEFT/RIGHT switch and raise the
VARIABLE COLLECTOR SUPPLY voltage until the desired value of
drain current is obtained. RDS(on) is obtained from the trace by reading
the peak values of current and voltage (see Figures 7and 8).
RDS(on) = VDS/ID.
Logic level devices would have different settings for 6, 7 and 8 so that the
on-resistance is measured at the specified gate voltage
1PER
V
E
AR
T
DIV
500PER
H
O
R
Z
mV
DIV
Figure 7. Drain-source resistance, pulsed mode
1PER
V
E
AR
T
DIV
500PER
H
O
R
Z
mV
DIV
8. VSD
Figure 8. Drain-source resistance
This is the source-drain voltage at rated current with VGS = 0. It is the forward voltage drop of the body-drain diode when
carrying rated current. If pulsed mode testing is required, use high current test fixture.
1. Connect the device as follows: gate to “B”, drain to “C”, source to “E”.
2. Set the MAX PEAK VOLTS to 15V.
3. Set the SERIES RESISTOR at 1.4 ohms or a value sufficiently low
that rated current can be obtained.
4. Set POLARITY to PNP.
5. Set MODE to "NORM".
6. The 80 microsec button of the PULSED STEPS selector should be IN
(or the 300 microsec, if the 80 is not available).
7. The CONNECTION SELECTOR should be set to the "SHORT"
position in the “EMITTER GROUNDED” sector.
8. HORIZONTAL VOLTS/DIV should be on 200 mV/div.
9. VERTICAL CURRENT DIV should be on 1 amp/div.
10.The DISPLAY button should be set to invert.
1PER
V
E
AR
T
DIV
200PER
H
O
R
Z
mV
DIV
To Order
Figure 9. Source-drain voltage (diode)
5 Page 
Index
AN-957 (v.Int)
POSITION
1
MEASUREMENT
IGSS
2 RDS(on)
3 BVDSS / IDSS / VDS
4 VGS(th)
COMMENT
C sense disconnected, Drain Source S/C connected, Collector Voltage applied to
gate via 330Ω resistor. Note: Gate protected by back to back 30V zeners.
Collector Voltage applied to DrainBased Voltage applied to Gate via 330Ω resistor.
Collector Voltage applied to Drain, Gate Source S/C connected via 330Ω resistor.
Collector Voltage applied to Drain, Gate Drain S/C connected via 330Ω resistor.
Related topics:
Parameter definition in IGBTs
Gate Charge
Thermal characteristics
ESD sensitivity
ESD test methods
To Order
11 Page | ||
| Páginas | Total 13 Páginas | |
| PDF Descargar | [ Datasheet AN957.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| AN95102 | Low Power Single/Dual Ferquency Synthesizers |  Philips |
| AN9515 | Multiplier Improcers the Dynamic Range of Echo Systems |  Intersil |
| AN957 | Measuring HEXFETCharacteristics | ETC |
| AN957 | Measuring HEXFETCharacteristics | ETC |
| 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 |