Application Notes

AN10393
BISS transistors and MEGA Schottky rectifiers - improved
technologies for discrete semiconductors
Rev. 01.00 — 01 September 2005
Application note
Document information
Info
Content
Keywords
BISS transistor, MEGA Schottky rectifier, DC/DC converter, Loadswitch,
Blocking diode, Medium power, PBSS4240V, PBSS4350T, PBSS4320T,
PMEG2010AEJ, PMEG1020EJ, PMEG6010AED, SOD323F, SOT666
Abstract
This application note provides detailed information on recent product
developments in the area of bipolar transistors and Schottky rectifiers
which enable the designer to save cost and to improve the performance
of electronic circuits.
AN10393
Philips Semiconductors
BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
Revision history
Rev
Date
Description
01
20050901
Initial document
Contact information
For additional information, please visit: http://www.semiconductors.philips.com
For sales office addresses, please send an email to: [email protected]
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Application note
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AN10393
Philips Semiconductors
BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
1. Introduction
Compared to integrated circuits, progresses in the development of discrete
semiconductors are not well known. Optimized design results in lower loss and
considerably improved thermal conductivity with discrete devices, as is demonstrated in
the example of transistors with low collector-emitter saturation voltage and Schottky
rectifiers with very low forward voltage drop.
The collector power dissipation PC = VCEsat x IC is a major contributor to losses in bipolar
transistors. Since the collector current IC is predefined by the application, the device
manufacturer has only the option to reduce the losses in the transistor by reducing the
collector-emitter saturation voltage VCEsat. With so-called low VCEsat transistors, this is
essentially achieved by the use of the mesh-emitter technology.
With the mesh-emitter design, the emitter series resistance is reduced by spreading the
emitter region over a much larger area and by contacting it from the base as a mesh.
This results in an evenly driven base, providing a more efficient use of the active emitter
area on the die and thus a significantly lower collector-emitter saturation voltage (Fig 1).
a.
b.
Fig 1. The die layout of a mesh-emitter transistor (a.) clearly shows the characteristic finger structure.
Compared to the typical die layout of a conventional transistor (b.), a mesh-emitter transistor’s finger
structure and base contact holes provide a much larger active area.
Enlarging the die area within the limits provided by the respective package allows a further reduction of the occurring losses. The development of new lead frames and the use
of 6pin packages (e.g. SOT457, SOT666) also allow a better heat dissipation (Fig 2).
a.
b.
c.
Fig 2. The standard lead frame of the SOT23 package (a.) limits the silicon area to about 0.5 mm2. The lead
frame of the SOT23 MaxSi (b.) permits to double the die area, and the SOT457 (c.) even provides a usable
Si area of 1.85 mm2.
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Philips Semiconductors
BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
2. Higher-performance transistors in smaller packages
The mesh-emitter technology has enabled the development of more powerful and, at the
same time, smaller transistors that Philips identifies by the abbreviation BISS
(Breakthrough In Small Signal). The comparison between the conventional 500 mA
transistor BC817-40 in a SOT23 package and the BISS transistor PBSS4240V in a
SOT666 package (Table 1:) clearly shows the advantages of the new design: smaller
mounting surface, higher maximum collector current IC max, higher maximum power
dissipation Ptot, lower saturation voltage VCEsat and higher current gain hFE even at high
collector current.
Table 1:
The BISS transistors have a smaller footprint – with a 42 % smaller package size
– while providing improved characteristics due to the mesh-emitter technology.
BC817-40
PBSS4240V
Package
SOT23
SOT666
Mounting area
8.2 mm²
4.8 mm²
IC max
0.5 A
2A
VCEO max
45 V
40 V
Ptot
0.25 W
0.3 W
VCEsat max at IC = 0.5 A; IB = 50 mA
700 mV
100 mV
VCEsat max at IC = 2 A; IB = 200 mA
–
400 mV
hFE min at IC = 0.5 A
40
300
These improved characteristics of the mesh-emitter transistor PBSS4240V are the result
of the combination and optimization of all parameters that were mentioned in the
previous paragraph. For example, the voltage drop at IC = 0.5 A is only 80 mV for the
PBSS4240V, compared to 200 mV for the BC817 (Fig 3). Multiplication of these values
by the collector current yields values for the collector dissipation of PC = 40 mW
compared to PC = 100 mW, i.e. a reduction by 60 % due to the mesh-emitter design. The
difference is even greater for the resulting temperature increase (∆T = 17 K compared to
∆T = 50 K), since the lower heat transfer resistance Rth of the SOT666 package adds to
the effect (∆T = PC x Rth).
Users can operate the BISS transistor at a higher ambient temperature without
exceeding the maximum allowable die temperature of 150 °C, or they can benefit from
the lower heat generation on the board. The lower power dissipation of the transistor also
helps extend the operating time of battery-powered devices. To further reduce the power
dissipation, transistors with lower VCE0 (e.g. 20 V) can be used, which provide an even
lower collector-emitter saturation voltage (e.g. PBSS4320T).
Typical for bipolar transistors is the current gain drop at high collector currents. With
mesh-emitter transistors, this characteristic is only present at significantly higher
currents, due to their higher collector current capability. Fig 4 illustrates this in a
comparison of the types mentioned above. At a collector current of IC = 0.5 A, the current
gain of the BC817-40 is already reduced to 34 % of its original value, while that of the
much smaller PBSS4240V is still at 75 %. If the PBSS4350T is used (same package as
BC817-40) the current gain is only reduced to 90 %.
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AN10393
Philips Semiconductors
BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
500
VCEsat [mV]
100
BC817-40
PBSS4240V
Tj = 25 °C
IC / IB = 10
typical values
10
5
1
Fig 3.
10
100
IC [mA]
1000
3000
The reduced saturation voltage VCEsat and the high collector current capability of the mesh-emitter transistor (PBSS4240V) as compared to a conventional transistor (BC817-40) enables 2 A continuous collector
current and 70 mV collector-emitter saturation voltage in a SOT666 package comparable to 0603 resistors.
120
normalised hFE [%]
100
80
PBSS4240V
60
BC817-40
Tj = 25 °C
40
VCE = 1 V
typical values
20
1
10
100
500
1000
3000
IC [mA]
Fig 4. Mesh-emitter transistors (PBSS4240V) provide a higher current gain than conventional transistors
(BC817-40).
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AN10393
Philips Semiconductors
BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
3. BISS transistors in SOT23 package are comparable to medium power
transistors
With conventional transistor designs, the die size that is often required for the necessary
collector current limits further miniaturization. For example, transistors with collector
currents > 0.5 A are not feasible in a SOT23 package using the traditional design. If, on
the other hand, the mesh-emitter technology is used, transistors in this package can
already provide collector currents of more than 2 A. Therefore, a mesh-emitter transistor
(SOT23) can replace a much larger transistor in an SOT223 package at comparable or
sometimes even better characteristics. Table 2: compares the BISS transistors
PBSS4350T and PBSS4320T with a medium-power transistor BDP31.
Table 2:
The much smaller BISS transistors in SOT23 packages can replace conventional
medium power transistors whose package is more than five times larger (SOT223).
BDP31
PBSS4350T
PBSS4320T
Package
SOT223 (SC-73)
SOT23
SOT23
Mounting area
46 mm²
8.2 mm²
8.2 mm²
IC max
3A
2A
2A
ICRP
–
3A
3A
VCEO max
45 V
50 V
20 V
Ptot
1.35 W
0.3 W
0.3 W
VCEsat max at IC = 0.5 A; IB = 50 mA
300 mV
80 mV
70 mV
VCEsat max at IC = 2 A; IB = 200 mA
700 mV
260 mV
210 mV
hFE min at IC = 2 A
20
200
200
A detailed curve of the collector-emitter saturation voltage of the three transistors is
shown in Fig 5. The saturation voltage of the mesh-emitter transistors at a collector
current of 1 A is about 40 % to 50 % lower than with a conventional transistor although it
is driven only with 50 mA (IC / IB = 20) instead of 100 mA (IC / IB = 10). An SOT23
transistor requires less than 20 % board space than a SOT223 type. Mounted on a
ceramic substrate, the power dissipation of a transistor in a SOT23 package can even be
increased to 625 mW. Suitable alternatives are transistors in 6pin packages (e.g.
SOT457) that can withstand a maximum power dissipation of 600 mW with a collector
heatsink area of 1 cm².
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Application note
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AN10393
Philips Semiconductors
BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
300
100
VCEsat [mV]
50
BDP31 (IC/IB = 10)
10
PBSS4350T (IC/IB = 20)
Ta = 27 °C
typical values
PBSS4320T (IC/IB = 20)
3
1
10
100
1000
3000
IC [mA]
Fig 5. The reduced saturation voltage VCEsat of the mesh-emitter transistor (PBSS-types) as compared to a conventional transistor (BC817) significantly reduces the collector power dissipation. Mesh-emitter transistors
produce less heat, allow high collector currents and can therefore replace medium power transistors.
4. Transistors with low saturation voltage cost less
Since the overall costs of a transistor are largely influenced by the costs of its package, a
transistor in a SOT23 package costs much less than a transistor in a bulkier SOT223
package. Users can further reduce costs by replacing expensive MOSFETs with meshemitter transistors. However, this will require some further considerations:
The resistance RCEsat, which is obtained by dividing VCEsat by IC, is directly comparable to
the on resistance RDS(on) of the MOSFET. But, a significant difference becomes obvious
when comparing the drive modes: Bipolar transistors are current-controlled while
MOSFETs are voltage-controlled, which results in some additional base power
dissipation for the former ones. An advantage is the lower base-emitter saturation
voltage of about 1 V, which is especially effective in the widely used circuits with supply
voltages below 3.3 V. MOSFETs exhibit a higher RDS(on) at low gate-source voltages.
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AN10393
Philips Semiconductors
BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
5. Application: Low-side switch
The advantages of higher efficiency, reduced temperature increase and available output
voltage are demonstrated in the example of the low-side switch shown in Fig 6. The
supply voltage VCC is 3.3 V, the load current is ILoad = IC = 0.5 A. The conventional
transistor BC817 with the mesh-emitter transistor PBSS4320T, both in a SOT23 package
are compared. The transistors are characterized by the values given in Table 1: and
Table 2:.
VCC
RLoad
S1
RB
VLoad
ILoad
Tr1
IB
VBEsat
Fig 6. A smaller package, lower power dissipation, higher efficiency: BISS transistors
offer advantages over the conventional transistors, as can be illustrated with this
simple switch application.
The temperature increase ∆T is calculated from the total power dissipation Ptot and the
heat transfer resistance Rth:
∆T = Ptot x Rth
= (PC + PB) x Rth
= (VCEsat x IC + VBEsat x IB) x Rth
∆T is calculated as 202 K for the transistor BC817 and as 38 K for the BISS transistor
PBSS4320T, assuming standard mounting conditions without additional heatsink areas.
At an ambient temperature of 25 °C, this means that the transistor BC817 cannot be
used under these conditions because the maximum permitted junction temperature of
150 °C would be exceeded. While a larger collector heatsink area or the use of a
medium-power transistor would solve the problem, it would also increase the costs.
Thus, the better choice is the BISS transistor.
It is important for a number of applications that the available output voltage VLoad matches
the supply voltage as closely as possible. VLoad is calculated as the difference between
the supply voltage VCC and the collector-emitter saturation voltage VCEsat at only 2.6 V for
the standard transistor BC817, compared to 3.23 V for the mesh-emitter transistor
PBSS4320T.
The efficiency h results from the ratio of the load power PLoad and the supply voltage PCC:
η = PLoad / PCC
= [(VCC - VCEsat) x IC] / [VCC x (IC – IB) ]
While only a circuit efficiency of 72 % can be achieved using the standard transistor
BC817, this increases to 89 % for the mesh-emitter transistor PBSS4320T. This very
simple example shows how the use of transistors with low saturation voltage can improve
key circuit parameters.
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AN10393
Philips Semiconductors
BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
6. Less loss in Schottky rectifiers combined with reduced device size
With diodes, the forward power dissipation PF = IF x VF is a major contributor to the
overall loss. Since the diode current IF is predetermined by the application, the diode
manufacturer can only reduce the power dissipation by reducing the forward voltage drop
(VF). For Schottky rectifiers, the forward voltage VF depends on the barrier level of the
metal used and of the active area.
Reducing the forward voltage VF by enlarging the active area conflicts with the
requirement of miniaturization and increases the circuit losses due to the increased diode
capacitance CD. It should also be considered that the reverse current IR will increase
when the forward voltage decreases. For the development of its so-called MEGA
(Maximum Efficiency General Application) Schottky rectifiers, Philips has therefore
chosen the barrier so that either the forward voltage is minimized or the reverse current
is minimized at a still low forward voltage level. Further, the die size area could be
reduced to mount these rectifiers in advanced, very small low-signal packages (e.g.
SOD323F, SOD523).
In order to further reduce the forward voltage, the thickness of the silicon die was
reduced, and the ratio of die area and lead frame area was optimized.
7. Smaller package, same performance
Today, Schottky rectifiers in large packages such as SMA, SMB and SOD123 still
dominate the market for currents between 0.5 A and 3 A. These are unreasonably bulky
for applications such as Point-of-Load DC/DC converters. Now, the MEGA technology
enables the development of rectifiers in smaller packages (SOD323F and SOD523) with
forward currents of 0.5 A to 2 A.
Table 3: compares the key characteristics of the widely used diodes SS12 or SS14,
respectively, to the new MEGA Schottky rectifiers PMEG1020EJ and PMEG2010EJ. The
smaller SOD323F rectifiers either have a forward voltage that is similar to that of the
SMA diode (PMEG2010EJ) or is significantly reduced (PMEG1020EJ). A comparison of
the reverse currents is only possible to a limited degree because these are published for
different reverse voltages, but still provides an impression of the order of magnitude.
Table 3:
Despite providing similar characteristics as common Schottky diodes, the MEGA
Schottky rectifiers require much smaller packages.
SS12 / SS14
PMEG2010AEJ
PMEG1020EJ
PMEG6010AED
Package
SMA
SOD323F
(SC-90)
SOD323F
(SC-90)
SOT457
(SC-74)
Mounting area
18.3 mm²
4.4 mm²
4.4 mm²
10.7 mm²
IF max
1A
1A
2A
1A
VR max
20 V / 40 V
20 V
10 V
60 V
VF max at IF = 1 A
500 mV
550 mV
350 mV
650 mV
IR max
200 µA
at VR = VR max
50 µA
at VR = 15 V
3000 µA
at VR = 10 V
350 µA
at VR = 60 V
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Application note
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AN10393
Philips Semiconductors
BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
2000
SS14
SMA
IF [mA]
1000
100
PMEG1020EJ
PMEG2010AEJ
PMEG6010AED
SOD323F (SC-90)
SOD323F (SC-90)
SOT457 (SC-74)
10
1
0
100
200
300
400
500
600
VF [mV]
Fig 7.
MEGA Schottky rectifiers (PMEG-types) are much smaller (SOD323F, SOT457) than conventional Schottky
diodes (SS14 in SMA). The forward voltage VF is equivalent or even lower.
2000
1000
PMEG1020EJ
IR [µA]
SOD323F (SC-90)
100
PMEG2010AEJ
SOD323F (SC-90)
SS14
SMA
10
PMEG6010AED
SOT457 (SC-74)
1
0
10
20
30
40
VR [V]
Fig 8. The reverse current IR of the MEGA Schottky rectifier (PMEG-types) is in the same order of magnitude as
with conventional Schottky rectifiers (SS14). Applications in which the reverse current is less critical can
benefit from devices with extremely low forward voltage (PMEG1020EJ).
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Philips Semiconductors
BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
The characteristics in Fig 7 and Fig 8 show the typical forward and reverse behavior. The
forward voltage VF and the reverse current IR of the PMEG2010EJ rectifier are similar to
those of the SS12 and SS14 diodes. If an application requires an even lower forward
voltage drop the MEGA Schottky rectifier PMEG1020EJ provides it, but at the expense of
a higher reverse current. This makes this type attractive for applications with a relatively
high duty cycle, i.e. a long on-time.
Some applications such as battery chargers require diodes with a reverse current that is
as low as possible in order to prevent the battery from discharging via the charger when
this is not connected to power. At the same time, losses in charging mode should be as
low as possible. During the development of the PMEG6010AED rectifier, care was therefore taken to minimize the reverse current at a low forward voltage. Although this diode is
mounted in the smaller SOT457 package, the forward voltage and the reverse current
are equivalent to those of the SS12 and SS14 diodes in the SMA package (Table 3:).
8. Application: Reverse polarity protection diode and OR’ing
This simple circuit example of a reverse voltage protection diode in a battery-powered
device compares a MEGA Schottky diode (PMEG1020EJ and PMEG2010AEJ) to a
standard Schottky diode of the SS12 or SS14 type with respect to temperature increase,
voltage drop and efficiency. It is assumed that the battery voltage in this example is 3 V,
and the device’s current consumption is 1 A.
VBat
VCC
Fig 9. A MEGA Schottky rectifier offers the same performance than a SMA rectifier on
25 % board space.
The internal temperature rise ∆T is calculated by multiplying the forward power
dissipation PF by the thermal resistance Rth j-s. The resulting values are about 17 K for
the SS12, 19 K for the PMEG1020EJ and 30 K for the PMEG2010EJ.
Although the PMEG1020EJ rectifier is mounted in a much smaller package, its
temperature increase is about the same to that of the much larger SMA diode, which is
due to the lower forward voltage. The relatively high temperature increase of the
PMEG2010AEJ is caused by the higher forward voltage combined with the higher
thermal resistance of the much smaller package but is still admissible.
To use as much of the full battery voltage as possible, the voltage drop across the
reverse polarity protection diode should be minimized. When the PMEG1020EJ rectifier
is used, 2.65 V are available to supply the circuits, while about 2.5 V are available when
the SS12 or PMEG2010AEJ rectifiers are used. The efficiency is calculated from the ratio
of the operating voltage VCC and the battery voltage VBat and is 88 % for the
PMEG1020EJ, compared to about 82 % for the SS12 and PMEG2010AEJ rectifiers.
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Philips Semiconductors
BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
If several DC/DC converters shall be connected in series, these must be decoupled via
diodes (OR’ing diodes). The above statements for reverse voltage protection diodes also
apply to this application. In addition, the failure case “short-circuit on output” of a DC/DC
converter should be considered: The associated diode will now operate under reverse
conditions after heating up in forward direction. The resulting higher junction temperature
significantly increases the reverse current. If, after making the switch, the reverse power
dissipation PR = VR x IR causes an additional temperature increase, the diode will be
damaged due to thermal runaway. This can be prevented by reducing the thermal
resistance Rth through the use of larger solder pads or by choosing a diode with a lower
reverse current but with higher forward voltage. Therefore, the selection of the “right”
diode – here PMEG1020 or PMEG2010 – will depend upon the decision whether the
reverse current is still acceptable in a specific application.
DC/DC-converter 1
Electronic circuit
DC/DC-converter 2
Fig 10. Using the lowest possible forward voltage drop requires careful observation of
the resulting reverse current.
The MEGA Schottky rectifier diodes meet or even exceed the characteristics of much
larger rectifiers. Users benefit from a better efficiency of the device due to lower losses
and from a more space-efficient design due to the use of smaller packages.
9. Summary
Advances in design and improved packages made it possible to develop optimized
discrete semiconductor devices, such as transistors with low saturation voltage and
Schottky rectifiers with very low forward voltage, that meet today’s increased
requirements for end products in terms of heat generation, efficiency, space and costs.
They are preferred solutions for use in portable, battery-powered devices (e.g. notebook
PCs, digital cameras) as well as in automotive applications for load switching and in
power supply systems.
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BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
10. Annex
Structure of a bipolar transistor
A bipolar transistor is built up from three different layers: a highly doped emitter layer, the
medium doped base area and a low doped collector area. The entire transistor is built in
the epitaxial layer. The highly doped substrate serves as a lead frame and lowimpedance conductor. During the assembly process of the die in the lead frame, it must
be noted that the backside is electrically active, contrary to ICs. The die is connected to
the lead frame by eutectic soldering or conductive gluing. Bond wires connect the base
and emitter contacts to the corresponding leads (Fig 11).
Saturation
A bipolar transistor is saturated when the collector-emitter voltage VCE is lower than or
equal to the base-emitter voltage VBE. The condition of VCE < VBE can be easily met in the
emitter circuit but not in the collector circuit due to the fact that the base voltage can
usually not exceed the collector voltage, which is equal to the supply voltage. The current
gain IC / IB that is forced by the external circuitry is lower than the DC current gain hFE.
The collector current IC will only increase slightly with a higher base current IB. The
deeper the saturation, i.e. the smaller the ratio IC / IB, the lower will the collector-emitter
saturation voltage VCEsat be. A disadvantage is that the base power dissipation
PB = VCEsat x IB and the turn-off time toff of the transistor will increase.
Structure of a Schottky diode
The Schottky diode consists of a medium doped epitaxial layer with a metallization. The
resulting metal-to-silicon junction is characterized by a low forward voltage VF and a short
reverse recovery time trr. The guard ring forms a parasitic PN diode to prevent local
magnification of field strength, significantly improving the forward breakdown
performance. The highly doped substrate serves as lead frame and low-impedance
conductor. Contrary to integrated circuits, the backside is electrically active, which
requires a low-impedance connection between the die and the lead frame. This is
implemented either by eutectic soldering or gluing. A bond wire connects the anode to
the lead frame (Fig 12).
Emitter
Base
+
n
Epitaxial-Layer:
≈20 µm
p
-
n
Substrate:
150 to 200 µm
≈
+
n
≈
Guard-Ring
Metallisation:
1 to 2 µm
Epitaxial-Layer:
2 to 6 µm
Substrate:
150 to 200 µm
Collector
p
≈
-
n
+
n
≈
Cathode
Fig 11. Bipolar transistor cross-section: The transistor
is located in the epitaxial layer. As for diodes the
much thicker substrate serves as carrier only.
Fig 12. Schottky diode cross-section: The comprises of
a metal alloy on a thin epitaxial layer. As for
transistors the reverse side is electrically active.
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BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
11. Disclaimers
Life support — These products are not designed for use in life support
appliances, devices, or systems where malfunction of these products can
reasonably be expected to result in personal injury. Philips Semiconductors
customers using or selling these products for use in such applications do so
at their own risk and agree to fully indemnify Philips Semiconductors for any
damages resulting from such application.
Right to make changes — Philips Semiconductors reserves the right to
make changes in the products - including circuits, standard cells, and/or
software - described or contained herein in order to improve design and/or
performance. When the product is in full production (status ‘Production’),
relevant changes will be communicated via a Customer Product/Process
Change Notification (CPCN). Philips Semiconductors assumes no
responsibility or liability for the use of any of these products, conveys no
licence or title under any patent, copyright, or mask work right to these
products, and makes no representations or warranties that these products
are free from patent, copyright, or mask work right infringement, unless
otherwise specified.
Application information — Applications that are described herein for any of
these products are for illustrative purposes only. Philips Semiconductors
make no representation or warranty that such applications will be suitable for
the specified use without further testing or modification.
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BISS transistors and MEGA Schottky rectifiers - improved technologies for discrete semiconductors
12. Contents
1.
Introduction .........................................................3
2.
Higher-performance transistors in smaller
packages ..............................................................4
3.
BISS transistors in SOT23 package are
comparable to medium power transistors ........6
4.
Transistors with low saturation voltage cost
less .......................................................................7
5.
Application: Low-side switch .............................8
6.
Less loss in Schottky rectifiers combined with
reduced device size ............................................9
7.
Smaller package, same performance ................9
8.
Application: Reverse polarity protection diode
and OR’ing .........................................................11
9.
Summary ............................................................12
10.
Annex .................................................................13
11.
Disclaimers ........................................................14
12.
Contents.............................................................15
© Koninklijke Philips Electronics N.V. 2005
All rights are reserved. Reproduction in whole or in part is prohibited without the prior
written consent of the copyright owner. The information presented in this document does
not form part of any quotation or contract, is believed to be accurate and reliable and may
be changed without notice. No liability will be accepted by the publisher for any
consequence of its use. Publication thereof does not convey nor imply any license under
patent- or other industrial or intellectual property rights.
Date of release:01 September 2005
Document number: <12NC>
Published in Germany
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