SCR/GTO/Diode POW-R-BLOK Modules ratings and

Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
1.0 POW-R-BLOK™ Module
Construction
Powerex POW-R-BLOK™
modules are hybrid assemblies
consisting of various combinations
of diodes and Silicon Controlled
Rectifiers (SCRs). The metal
baseplate of a POW-R-BLOK™
module is electrically isolated from
the power devices. The isolated
baseplate construction allows a
number of POW-R-BLOK™
modules to be mounted on a
common heatsink, greatly
simplifying equipment assembly.
Chips are mounted to the
baseplate within the package in
two different ways. In lower power
modules, the power chip is
soldered to molybdenum discs.
The molybdenum discs alleviate
thermal stress on the chip due to
the nearly equivalent thermal
expansion coefficients of
molybdenum and silicon. Both
surfaces of this assembly are next
soldered to the power terminals.
The higher power modules use a
pressure contact system to hold
the chip against the power
terminals.
Isolation of the power chips from
the baseplate is achieved with
various materials. The lower power
modules typically utilize aluminum
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
oxide, while the higher power
modules utilize beryllium oxide
(BeO). BeO has superior thermal
conductivity, but it is more
expensive and can be a personal
health hazard. POW-R-BLOK™
modules which may contain BeO
have the following caution printed
on their data sheet:
WARNING:
Internal insulation used is
Beryllium Oxide. User should
avoid grinding, crushing or
abrading these portions. Care
must be exercised in properly
disposing of unwanted
modules.
The isolation materials used are
selected to withstand 2000 to
2500 volts from live parts to the
baseplate without significantly
adding to the device’s thermal
resistance.
Many of the POW-R-BLOK™
modules have been tested and
recognized by Underwriters
Laboratories (QQQX2 Power
Switching Semiconductors). UL
Recognition is an on-going
process for POW-R-BLOK™
modules. Please contact your local
Powerex sales representative for
the latest information on UL
Recognition of POW-R-BLOK™
modules.
vii
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
Figure 1.1 Schematic Symbol, Terminal Designations and Current
Voltage Characteristics of a Diode (Rectifier).
1.1 SCR/GTO/Diode
POW-R-BLOK™ Module
Configurations
The schematic symbol, terminal
designations, and output currentvoltage characteristic for diodes
and SCRs are shown in Figures
1.1 and 1.2 respectively. The GTO
is a special case of the SCR which
can be turned off with a sufficiently
high pulse of reverse gate current.
Diodes are often also called rectifiers. Either term may be used
interchangeably. SCRs are a
member of the thyristor family of
devices. The term thyristor defines
any semiconductor switch whose
bistable action depends upon
p-n-p-n regenerative feedback.
The SCR is classified as a reverse
blocking triode thyristor.
SCHEMATIC SYMBOL AND
TERMINAL DESIGNATIONS
+
VF
—
CURRENT VOLTAGE CHARACTERISTIC
IF
(A) Anode
IF
Maximum
Non-Repetitive
Peak Reverse
Voltage VRSM
(K) Cathode
On-State
Maximum
Repetitive
Peak Reverse
Voltage VRRM
VF
Reverse
Blocking
State
IRRM
Figure 1.2 Schematic Symbol, Terminal Designations and Current Voltage Characteristics of an SCR.
SCHEMATIC SYMBOL AND
TERMINAL DESIGNATIONS
(A) Anode
CURRENT VOLTAGE CHARACTERISTICS
IT
+
IG
VT
(G) Gate
—
+ VG —
(K) Cathode
IT
On-State
Maximum Non-Repetitive Peak
Reverse Voltage VRSM
Maximum Repetitive
Peak Reverse
Voltage VRRM
IRRM
Holding Current
Negitive Differential
Resistance Region
IDRM
VT
Off-State
Reverse
Blocking
State
Breakover
Voltage
V(BO)With
Gate Signal
Maximum Repetitive
Peak Off-State
Voltage VDRM
Maximum Non-Repetitive
Peak Off-State
Voltage VDSM
Breakover Voltage V(BO)
Gate Open
viii
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
1.2 Typical Applications
Some of the typical applications
for POW-R-BLOK™ modules are:
UPS, inverters, lighting controls,
induction heating, ultrasonic
cleaning, battery chargers, AC and
DC motor control, high frequency
welding, and power supplies. To
meet such a diverse range of
applications, POW-R-BLOK™
modules are available in
a wide range of circuit
configurations, as illustrated by
Table 1.1.
Table 1.1
POW-R-BLOK™ Module Circuit Configurations.
SCR/DIODE (HALF CONTROL) MODULES
DIODE MODULES
Single
CS Series
Dual
CD_1 Series
ED_1 Series
Common
Cathode
CC Series
EC Series
Common
Anode
CN Series
EN Series
Reverse
Dual
Three
Phase
Bridge
SCR/Diode
CM_2 Series
CD_2 Series
ED_2 Series
CD_B Series
Diode/SCR
CD_7 Series
ED_7 Series
CD_C Series
CD_9 Series
Diode/SCR
Center Tap
CC_2 Series
EC_2 Series
ME Series
SCR/Diode
Center Tap
CN_7 Series
EN_7 Series
Split
SCR/Diode
CT_2 Series
*
SCR/Diode
CE_2 Series
Three-Phase
Bridge
DUAL SCR (FULL CONTROL) MODULES
Dual SCR
*
Split
Dual SCR
CM_3 Series
CD_3 Series
ED_3 Series
CD_A Series
CT_3 Series
*Auxiliary Cathode Terminal Not Available On All Module Types
GTO BRIK
*Auxiliary Cathode Terminal Not Available On All Module Types
ix
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
1.3 The Device Data Sheet
The proper application of power
semiconductors requires an
understanding of their maximum
ratings and electrical
characteristics, information which
is presented within the device
data sheet. Good design practice
employs data sheet limits and not
information obtained from small
sample lots.
Table 1.2
A rating is a maximum or minimum
value that sets a limit on device
capability. Operation in excess of
a rating can result in irreversible
degration or device failure.
Maximum ratings represent
extreme capabilities of a device.
They are not to be used as design
conditions.
A characteristic is a measure of
device performance under
specified operating conditions
expressed by minimum, typical,
and/or maximum values, or shown
graphically.
Major Ratings and Characteristics of a Typical POW-R-BLOK™ Module.
Absolute Maximum Ratings
Characteristics
Symbol
Peak Forward Blocking Voltage
VDRM
VDSM
Transient Peak Forward Blocking Voltage (Non-Repetitive), t < 5ms
DC Forward Blocking Voltage
Peak Reverse Blocking Voltage
Transient Peak Reverse Blocking Voltage (Non-Repetitive), t < 5ms
DC Reverse Blocking Voltage
RMS On-State Current
VRSM
VR(DC)
IT(RMS), IF(RMS)
Average On-State Current, TC = 82°C
Peak One-Cycle Surge (Non-Repetitive) On-State Current (60Hz)
IT(AV), IF(AV)
ITSM, IF(TSM)
Peak One-Cycle Surge (Non-Repetitive) On-State Current (50Hz)
ITSM, IF(TSM)
I2t
I2t (for Fusing), 8.3 milliseconds
Critical Rate-of-Rise of On-State Current*
Peak Gate Power Dissipation
Average Gate Power Dissipation
Peak Forward Gate Voltage
Peak Reverse Gate Voltage
Peak Forward Gate Current
Storage Temperature
Operating Temperature
Maximum Mounting Torque M6 Mounting Screw
di/dt
PGM
PG(AV)
VGFM
VGRM
IGFM
TSTG
Tj
—
CM421690
Units
1200
1600
Volts
1350
1700
Volts
960
1280
Volts
1200
1600
Volts
1350
1700
Volts
960
1280
Volts
140
190
Amperes
90
90
Amperes
1800
1800
Amperes
1730
1730
Amperes
15000
15000
100
100
A2sec
Amperes/ms
5.0
5.0
Watts
0.5
0.5
Watts
10
5.0
10
Volts
Amperes
2.0
2.0
-40 to 125
-40 to 125
-40 to 125
-40 to 125
26
Volts
5.0
26
°C
°C
lb.-in.
Maximum Mounting Torque M5 Terminal Screw
—
17
17
lb.-in.
Module Weight (Typical)
—
160
160
Grams
2500
2500
V Isolation
*Tj = 125°C, IG = 1.0A, VD = 1/2 VDRM
x
VD(DC)
VRRM
CM421290
VRMS
Volts
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
Table 1.2 illustrates the major
ratings and characteristics of a
typical Powerex POW-R- BLOK™
SCR/Diode Module. Table 1.3 lists
the symbols and definitions of the
major device parameters for
diodes, SCRs, and GTOs.
Table 1.2
The remainder of this section on
ratings and characteristics will be
specific to SCRs. However, much
of the material is also applicable to
diodes and GTOs.
Major Ratings and Characteristics of a Typical POW-R-BLOK™ Module. (Continued)
Electrical and Thermal Characteristics, Tj = 25°C unless otherwise specified
Characteristics
Symbol
Test Conditions
IDRM
IRRM
Tj = 125°C, VDRM = Rated
Tj = 125°C, VRRM = Rated
Conducting State Maximums
Peak On-State Voltage
VFM
IFM = 270A, ITM = 270A
Switching Minimums
Critical Rate-of-Rise of Off-State Voltage
dv/dt
Tj = 125°C, VD = 2/3 VDRM
Ru(J-C)
Ru(C-S)
Per Module
0.3
°C/Watt
Per Module
0.2
°C/Watt
IGT
VGT
VGDM
VD = 6V, RL = 2V
VD = 6V, RL = 2V
Blocking State Maximums
Forward Leakage Current, Peak
Reverse Leakage Current, Peak
Thermal Maximums
Thermal Resistance, Junction-to-Case
Thermal Resistance, Case-to-Sink (Lubricated)
Gate Parameters Maximums
Gate Current-to-Trigger
Gate Voltage-to-Trigger
Non-Triggering Gate Voltage
Tj = 125°C, VD = 1/2 VDRM
CM421290/CM421690
Units
15
mA
15
mA
1.4
500
100
Volts
Volts/ms
mA
2.0
Volts
0.25
Volts
xi
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
Table 1.3
Symbols and Definitions of Major POW-R-BLOK™ Parameters
Power Semiconductor Devices, General Use
Symbol
Parameter
Definition/Description
Ru
Thermal Resistance
Defined when junction power dissipation results in a balanced state of thermal flow. Specifies the
degree of temperature rise per unit of power, measuring junction temperature from a specified
external point.
Ru(J-A)
Junction-to-Ambient
Thermal Resistance
The steady state thermal resistance between the junction and ambient.
Ru(J-C)
Junction-to-Case
Thermal Resistance
The steady state thermal resistance between the junction and surface of the case.
Ru(J-S)
Junction-to-Sink
Thermal Resistance
The steady state thermal resistance between the junction and the heatsink mounting surface.
Ru(C-S) Contact
Thermal Resistance
The steady state thermal resistance between the surface of the case and the heatsink
mounting surface.
Zu
Transient Thermal
Impedance
The change of temperature difference between two specified points or regions at the end of a time
interval divided by the step function change in power dissipation at the beginning of the same
interval causing the change of temperature difference.
Zu(J-A)
Junction-to-Ambient
Transient Thermal
Impedance
The transient thermal impedance between the junction and ambient.
Zu(J-C)
Junction-to-Case
Transient Thermal
Impedance
The transient thermal impedance between the junction and the surface of the case.
Zu(J-S)
Junction-to-Sink
Transient Thermal
Impedance
The transient thermal impedance between the junction and the heatsink mounting surface.
TA
Ambient
Temperature
When used in the natural cooling or forced-air cooling it is the temperature of the surrounding
atmosphere of a device which is dependent on geographical location and season, and is not
influenced by heat dissipation of the device.
TS
Sink Temperature
The temperature at a specified point on the device heatsink.
TC
Case Temperature
The temperature at a specified point on the device case.
Tj
Junction Temperature
Rating
The device junction temperature rating. Indicates the maximum and minimum allowable operation
temperatures.
TSTG
Storage Temperature
Rating
The device storage temperature (with no electrical connection). Indicates the maximum and
minimum allowable temperatures.
—
Mounting Torque
Mounting Screw
The maximum allowable torque specification for mounting a device to a heatsink with the
specified mounting screw.
—
Mounting Torque
Terminal Screw
The maximum allowable torque specification for tightening the specified electrical terminal screws.
SCR Modules
xii
VRRM
Peak Reverse
Blocking Voltage
Within the rated junction temperature range, and when there is no signal between the gate and
cathode, specifies the repetitive peak reverse anode to cathode voltage applicable on each cycle.
VRSM
Transient Peak Reverse
Blocking Voltage
Within the rated junction temperature range, and when there is no signal between the gate and
cathode, specifies the non-repetitive peak reverse anode to cathode voltage applicable for time
width equivalent to less than 5ms.
VR(DC)
DC Reverse Blocking
Voltage
Within the rated junction temperature range, and when there is no signal between the gate and
cathode, specifies the maximum value for DC anore to cathode voltage applicable in the reverse
direction.
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
Table 1.3
Symbols and Definitions of Major POW-R-BLOK™ Parameters (continued)
SCR Modules (continued)
Symbol
Parameter
Definition/Description
VDRM
Peak Forward
Blocking Voltage
Within the rated junction temperature range, and when there is no signal between the gate and
cathode, specifies the repetitive peak off-state anode to cathode voltage applicable for each cycle.
Includes the maximum instantaneous value for repetitive off-state voltage, but excludes
non-repetitive transient off-state voltage.
VDSM
Transient Peak Forward
Blocking Voltage
Within the rated junction temperature range and when there is no signal between the gate and
cathode, specifies the peak non-repetitive off-state anode to cathode voltage applicable for a time
width equivalent to less than 5ms. Indicates the maximum instantaneous value for non-repetitive
transient off-state voltage.
VD(DC)
DC Forward
Blocking Voltage
Within the rated junction temperature range and when there is no signal between the gate and
cathode, specifies maximum value for DC anode to cathode voltage applicable in the
forward direction.
dv/dt
Critical Rate-of-Rise
of Off-State Voltage
At maximum rated junction temperature, and when there is no signal between the gate and cathode,
specifies the maximum rate-of-rise of off-state voltage that will not drive the device from an off-state
when an exponential off-state voltage of specified amplitude is applied to the device.
dv = 0.632VD
dt
r
VTM
Peak On-State
Voltage
VD: Specified Off-State Voltage
r: Time constant for exponential waveform
At specified junction temperature, and when on-state current (commercial frequency, half sine wave
of specified peak amplitude) is applied to the device, indicates peak-value for the resulting
voltage drop.
IT(RMS) RMS On-State
Current
At specified case temperature, indicates the RMS value for on-state current that can be continuously
applied to the device.
IT(AV)
Average On-State
Current
At specified case temperature, and with the device connected to a resistive or inductive load,
indicates the average value for forward-current (sine half wave, commercial frequency) that can be
continuously applied to the device.
ITSM
Peak On-State
Current
Within the rated junction temperature range, indicates the peak-value for non-repetitive on-state
current (sine half wave, commercial frequency). This value indicated for one cycle, or as a function
of a number of cycles.
I2t
Current-Squared Time
The maximum, on-state, non-repetitive short time-thermal capacity of the device and is helpful in
selecting a fuse or providing a coordinated protection scheme of the device in the equipment. This
rating is intended specifically for operation less than one half cycle of a 180° (degree) conduction
angle sinusoidal wave form. NOTE: The off-state blocking capability cannot be guaranteed at values
near the maximum I2t.
di/dt
Critical Rate-of-Rise
of On-State Current
At specified case (or point) temperature, specified off-state voltage, specified gate conditions, and at
a frequency of less than 60Hz, indicates the maximum rate-of-rise of on-state current which the
thyristor will withstand after switching from an off-state to an on-state, when using recommended
gate drive.
IRRM
Reverse Leakage
Current, Peak
At maximum rated junction temperature, indicates the peak-value for reverse-current flow when a
voltage (sine half wave, commercial frequency, and having a peak value as specified for repetitive
peak reverse-voltage rating) is applied in a reverse direction to the device.
IDRM
Forward Leakage
Current, Peak
At maximum rated junction temperature, indicates the peak-value for off-state-current flow when a
voltage (sine half wave, commercial frequency, and having a peak value for repetitive off-state
voltage rating) is applied in a forward direction to the device.
PGM
Peak Gate Power
Dissipation
Within the rated junction temperature range, indicates the peak-value for maximum allowable power
dissipation over a specified time period, when the device is in forward conduction between the
gate and cathode.
PG(AV)
Average Gate Power
Dissipation
Within the rated junction temperature range, indicates the average value for maximum allowable
power dissipation when the device is forward-conducting between the gate and cathode.
xiii
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
Table 1.3
Symbols and Definitions of Major POW-R-BLOK™ Parameters (continued)
SCR Modules (continued)
Symbol
Parameter
Definition/Description
IGFM
Peak Forward Gate
Current
Within the rated junction temperature range, indicates the peak-value for forward-current flow
between the gate and cathode.
VGRM
Peak Reverse Gate
Voltage
Within the rated junction temperature range, indicates the peak-value for reverse-voltage
applied between the gate and cathode.
VGFM
Peak Forward Gate
Voltage
Within the rated junction temperature range, indicates the peak-value for forward-voltage
applied between the gate and cathode.
IGT
Gate Currentto-Trigger
At a junction temperature of 25°C, and with a specified off-voltage, and a specified load resistance,
indicates the minimum gate DC current required to switch the thyristor from an off-state to an
on-state.
VGT
Gate Voltageto-Trigger
At a junction temperature of 25°C, and with a specified off-state voltage, and a specified load
resistance, indicates the minimum gate DC voltage required to switch the thyristor from an off-state
to an on-state.
VGDM
Non-Triggering Gate
Voltage
At maximum rated junction temperature, and with a specified off-state voltage applied to the
device, indicates the maximum gate DC voltage which will not switch the device from an off-state
to an on-state.
ton
Turn-On Time
At specified junction temperature, and with a peak repetitive off-state voltage of half rated value,
followed by device turn-on using specified gate-current, when specified on-state current of specified
di/dt flows, indicated as the time required for the applied off-state voltage to drop to 10% of its initial
value after gate current application. “Delay time” is the term used to define the time required for
applied voltage to drop to 90% of its initial value following gate-current application, and the time
required for level to drop from 90% to 10% is referred to as “rise time”. The sum of both these
defines turn-on time.
tq
Turn-Off Time
Current
Voltage
tq
Time
Specified at maximum rated junction temperature. Device set up to conduct on-state current,
followed by application of specified reverse-voltage to quench on-state current, and then increasing
voltage at a specified rate-of-rise as determined by circuit conditions controlling the point where
specified off-state voltage is reached. Turn-off time defines the minimum time which the device will
hold its off-state, starting from the point on-state current reached zero, and after forward voltage
is again applied.
Diode Modules
xiv
VRRM
Peak Reverse
Blocking Voltage
Within the rated junction temperature range, specifies the repetitive peak reverse voltage applicable
for each cycle. Includes the maximum instantaneous value for repetitive transient reverse voltage,
but excludes non-repetitive transient reverse-voltage.
VRSM
Transient Peak Reverse
Blocking Voltage
Within the rated junction temperature range, specifies the non-repetitive peak reverse voltage
applicable for a time width equivalent to less than 5ms. Indicates the maximum instantaneous value
for non-repetitive transient voltage.
VR(DC)
DC Reverse
Blocking Voltage
The maximum value for DC voltage applicable in the reverse direction, specified within the rated
junction temperature range.
VFM
Peak On-State
Voltage
At specified junction temperature, and when forward-current (commercial frequency, sine wave of
specified peak amplitude) is applied to the device, indicates peak-value for the resulting
voltage drop.
IF(RMS) RMS On-State
Current
At specified case temperature, indicates the RMS value for forward-current that can be continuously
applied to the device.
IF(AV)
Average On-State
Current
At specified case temperature, and with the device connected to a resistive or inductive load,
indicates the average value for forward-current (sine half wave, commercial frequency) that can be
continuously applied to the device.
IFSM
Peak Surge On-State
Current
Within the rated junction temperature range, indicates the peak-value for non-repetitive
forward-current (sine half wave, commercial frequency), this value is defined at one cycle or as a
function of a number of cycles.
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
Table 1.3
Symbols and Definitions of Major POW-R-BLOK™ Parameters (continued)
Diode Modules (continued)
Symbol
Parameter
Definition/Description
I2t
Current-Squared Time
The maximum, on-state, non-repetitive short time-thermal capacity of the device and is helpful in
selecting a fuse or providing a coordinated protection scheme of the device in the equipment. This
rating is intended specifically for operation less than one half cycle of a 180° (degree) conduction
angle sinusoidal wave form. NOTE: The off-state blocking capability cannot be guaranteed at values
near the maximum I2t.
IRRM
Reverse Leakage
Current, Peak
At maximum rated junction temperature, indicates the peak-value for reverse-current flow when a
voltage (sine half wave, commercial frequency, and having a peak value as specified for repetitive
peak reverse-voltage rating) is applied in a reverse direction to the device.
Qrr
Reverse Recovery
Charge
Indicates the total amount of reverse recovery charge. Specified at a certain junction temperature,
and current which has decreased at a specified rate of decrease, from the forward state to reverse
after a certain forward current was applied.
GTO Modules
VRRM
Peak Reverse
Blocking Voltage
Within the rated junction temperature range, and when there is no signal between the gate and
cathode, specifies the peak repetitive reverse-voltage applicable on each cycle.
VRSM
Transient Peak Reverse
Blocking Voltage
Within the rated junction temperature range, and when there is no signal between the gate and
cathode, specifies the peak non-repetitive peak reverse voltage applicable for a time width
equivalent to less than 5ms.
VDRM
Peak Forward
Blocking Voltage
Within the rated junction temperature range, and when there is a specified reverse voltage between
the gate and cathode, specifies the peak repetitive off-state voltage applicable for each cycle.
Includes the maximum instantaneous value for repetitive transient off-state voltage, but excludes
non-repetitive off-state voltage.
VDSM
Transient Peak Forward
Blocking Voltage
Within the rated junction temperature range, and when there is a specified reverse voltage between
the gate and cathode, specifies the peak non-repetitive off-state voltage applicable for a time width
equivalent to less than 5ms. Indicates the maximum instantaneous value for non-repetitive transient
off-state voltage.
VD(DC)
DC Forward
Blocking Voltage
Within the rated junction temperature range, and when there is a specified reverse voltage between
the gate and cathode, specifies maximum value for DC voltage applicable in the forward direction.
dv/dt
Critical Rate-of-Rise
of Off-State Voltage
At maximum rated junction temperature, and when there is a specified reverse voltage between the
gate and cathode, specifies the maximum rate-of-rise of off-state voltage that will not drive the
device from an off-state to an on-state when an exponential off-state voltage of specified amplitude
is applied to the device.
dv = 0.632VD
dt
r
VTM
Peak On-State
Voltage
VD: Specified Off-State Voltage
r: Time constant for exponential waveform
At specified junction temperature, and when on-state current (commercial frequency, half sine wave
of specified peak amplitude) is applied to the device, indicates peak-value for the resulting voltage
drop.
IT(RMS) RMS On-State
Current
At specified case temperature, indicates the RMS value for on-state current that can be continuously
applied to the device.
IT(AV)
Average On-State
Current
At specified case temperature, and with the device connected to a resistive or inductive load,
indicates the average value for forward-current (sine half wave, commercial frequency) that can be
continuously applied to the device.
ITSM
Peak Surge On-State
Current
Within the rated junction temperature range, indicates the peak-value for non-repetitive on-state
current (sine half wave, commercial frequency). This value indicated for one cycle, or as a function
of a number of cycles.
xv
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
Table 1.3
Symbols and Definitions of Major POW-R-BLOK™ Parameters (continued)
GTO Modules (continued)
xvi
Symbol
Parameter
Definition/Description
I2t
Current-Squared Time
The maximum, on-state, non-repetitive short time-thermal capacity of the device and is helpful in
selecting a fuse or providing a coordinated protection scheme of the device in the equipment. This
rating is intended specifically for operation less than one half cycle of a 180° (degree) conduction
angle sinusoidal wave form. NOTE: The off-state blocking capability cannot be guaranteed at values
near the maximum I2t.
di/dt
Critical Rate-of-Rise
of On-State Current
At specified case (or point) temperature, specified off-state voltage, specified gate conditions, and at
a frequency of less than 60Hz, indicates the maximum rate-of-rise of on-state current which the
GTO will withstand after switching from an off-state to an on-state, when using recommended
gate drive.
IRRM
Reverse Leakage
Current, Peak
At maximum rated junction temperature, indicates the peak-value for reverse-current flow when a
voltage (a half sine wave, commercial frequency, and having a peak value as specified for repetitive
peak reverse-voltage rating) is applied in a reverse direction to the device.
IDRM
Forward Leakage
Current, Peak
At maximum rated junction temperature, indicates the peak-value for off-state-current flow when a
voltage (sine half wave, commercial frequency, and having a peak value as specified for repetitive
off-state voltage rating) is applied in a forward direction to the device. Tested with a specified reverse
voltage between the gate and cathode.
PGFM
Peak Gate Forward
Power Dissipation
Within the rated junction temperature range, indicates the peak-value for maximum allowable power
dissipation over a specified time period, when the device is forward conducting between the
gate and cathode.
PG(AV)
Average Gate Forward
Power Dissipation
Within the rated junction temperature range, indicates the average value for maximum allowable
power dissipation when the device is forward-conducting between the gate and cathode.
IGFM
Peak Forward Gate
Current
Within the rated junction temperature range, indicates the peak-value for forward-current flow
between the gate and cathode.
VGRM
Peak Reverse Gate
Voltage
Within the rated junction temperature range, indicates the peak-value for reverse-voltage
applied between the gate and cathode.
VGFM
Peak Forward Gate
Voltage
Within the rated junction temperature range, indicates the peak-value for forward-voltage
applied between the gate and cathode.
IGT
Gate Currentto-Trigger
At a junction temperature of 25°C, and with a specified off-voltage, and a specified load resistance,
indicates the minimum gate DC current required to switch the GTO from an off-state to an
on-state.
VGT
Gate Voltageto-Trigger
At a junction temperature of 25°C, and with a specified off-state voltage, and a specified load
resistance, indicates the minimum gate DC voltage required to switch the GTO from an off-state
to an on-state.
PGRM
Peak Gate Reverse
Power Dissipation
Within the rated junction temperature range, indicates the peak-value for maximum allowable power
dissipation in the reverse direction between the gate and cathode, over a specified time period.
PGR(AV) Average Gate Reverse
Power Dissipation
Within the rated junction temperature range, indicates the average value for maximum allowable
power dissipation in the reverse direction between the gate and cathode.
IGRM
Peak Reverse
Gate Current
Within the rated junction temperature range, indicates peak-value for reverse-current that can be
conducted between the gate and cathode.
ITGQ
Gate Controlled
Turn-off Current
Under specified conditions, indicates the instantaneous value for on-current usable in gate control,
specified immediately prior to device turn-off.
tgt
Turn-On Time
When applying forward-current to the gate, indicates the time required to switch the GTO from an
off-state to an on-state.
tgq
Turn-Off Time
When applying reverse-current to the gate, indicates the time required to switch the GTO from an
on-state to an off-state.
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
1.4 Voltage Ratings
The specified voltages are defined
by the maximum rating voltages
which can be applied between
anode and cathode in the forward,
(anode positive with respect to
the cathode), and the reverse
directions. The maximum voltage
ratings should never be exceeded.
Exceeding the maximum voltage
ratings can be detrimental to the
device, resulting in instant failure
or a decrease in the life of the
device.
The repetitive peak sinusoidal
forward voltage which can be
applied to an SCR or a GTO in the
off-state is specified by the Peak
Forward Blocking Voltage, VDRM.
The forward voltage applicable
for sine pulses of less than
5 milliseconds duration which can
be applied on a non-repetitive
basis to an SCR or a GTO in the
off-state is specified by the
Transient Peak Forward Blocking
Voltage, VDSM. The maximum
forward DC voltage rating for an
SCR or a GTO is specified by the
DC Forward Blocking Voltage,
VD(DC). Similar parameters exist
with respect to the reverse
direction, i.e. Peak Reverse
Blocking Voltage, VRRM; Transient
Peak Reverse Blocking Voltage,
VRSM; and DC Reverse Blocking
Voltage, VR(DC). The reverse
parameters are applicable to
diodes in addition to SCRs and
GTOs.
Voltage ratings are specified at
the maximum rated junction
temperature and are applicable
over the entire operating
temperature range. For most
SCRs, voltage ratings are
specified with the gate terminal
open. Of particular caution, users
should avoid applying positive
gate voltage during periods when
an SCR is blocking reverse
voltage. Positive gate bias during
reverse anode to cathode voltage
results in a significant increase in
SCR power dissipation which must
be accounted for to insure reliable
operation. For GTOs, voltage
ratings are specified with a
stipulated value of reverse gate to
cathode voltage. SCRs are
normally assigned the same
voltage rating in both the forward
and reverse directions. In practice,
most SCRs exhibit a slightly
higher reverse breakdown voltage,
and the forward breakdown
voltage sets the device rating.
Leakage currents are specified at
the device forward and reverse
voltage ratings. Leakage currents
are strongly temperature
dependent. At high junction
temperatures, it is possible to have
regenerative thermal runaway of
the device if the case to ambient
thermal resistance is at or above a
critical value. This potential high
power dissipation, particularly with
poor or no heatsinking is one
reason why it is not recommended
to measure blocking voltages of
diodes, SCRs, or GTOs with DC
tests.
Exceeding the forward blocking
voltage of an SCR will result
in triggering the device into
conduction. Voltage breakover is
generally not damaging providing
the allowable di/dt rating under this
condition is not exceeded. The
breakover voltage of an SCR is
highly temperature dependent,
decreasing rapidly above rated
junction temperature. It is not
recommended to trigger SCRs by
voltage breakover, rather a zener
diode or equivalent network should
be connected from anode to gate
so that the device is
triggered by gate drive.
1.5 dv/dt Rating
A high rate of off-state anode-tocathode voltage, dv/dt, may
cause an SCR to turn-on. The
static dv/dt test circuit and
standard waveforms are shown
in Figure 1.3.
Static dv/dt capability is an inverse
function of junction temperature.
Reverse biasing the gate with
respect to the cathode may
increase dv/dt withstand capability
for medium and low current SCRs.
Often the circuit designer will need
to add a snubber network across
the SCR to limit the maximum
dv/dt applied to an SCR.
Figure 1.3 Exponential dv/dt
Test Circuit and
Waveform
VO
63%
Numerical dv/dt
10%
Time
to
R1C1
4 R1C1
dv
V
dt (EXP) = 0.63 R oC
1 1
S1
+
VAA
—
R1
R2
To Scope
D. U. T.
R3
C1
Gate
Bias
S1 = Mercury Wetted Reed Relay or SCR
R1 = Noninducive Resistor
R2 = Current Limiting Resistor
xvii
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
1.6 Power Dissipation
The power generated in an SCR
consists of the following
components:
1. Turn-on switching
2. Conduction
3. Turn-off switching or
commutation
4. Blocking
5. Gate Circuit
On-state conduction losses are
the major source of junction
heating for normal duty cycles and
power frequencies. For very high
di/dt current waveforms or high
operating frequencies, turn-on
switching loss can become
significant.
Figure 1.4 illustrates a typical
curve of on-state power dissipation
in average watts for an SCR as a
function of average current in
amperes for various conduction
angles for operation up to 400 Hz.
These curves are based on a
Figure 1.4 On-State Power
Dissipation vs.
Average Current
Characteristic Curve
current waveform which is the
remainder of a half sine wave
which results from delayed angle
triggering in a single phase
resistive load circuit. Similar
curves are provided for
rectangular current waveforms.
These curves represent the
integrated product of the
instantaneous anode current and
on-state voltage drop, and the
integration of the appropriate
reverse blocking losses. Pulse
triggering is assumed and hence
gate losses are neglected.
1.7 Average and RMS Current
Ratings
Average current rating versus case
temperature as it appears in a
typical curve for an SCR is shown
in Figure 1.5. These curves specify
the maximum allowable average
anode current ratings of the SCR
as a function of case temperature
and conduction angle for a
resistive load operating up to
400 Hz. Points on this curve are
selected so that the junction
temperature does not exceed the
Figure 1.5 Average Current vs.
Case Temperature
Characteristic Curve
40
180o
35
u
360o
30
90o
RESISTIVE,
INDUCTIVE
LOAD PER
SINGLE
ELEMENT
25
20
120o
60o
u = 30o
15
10
5
0
0
5
10
15
20
AVERAGE ON-STATE CURRENT, IT(AV),
(AMPERES)
xviii
MAXIMUM ALLOWABLE CASE TEMPERATURE
(RECTANGULAR WAVEFORM)
MAXIMUM ALLOWABLE CASE TEMPERATURE, TC, (oC)
MAXIMUM POWER DISSIPATION, PAV(MAX), (WATTS)
MAXIMUM ON-STATE POWER DISSIPATION
(SINUSOIDAL WAVEFORM)
25
130
u
360o
120
110
RESISTIVE, INDUCTIVE
LOAD PER SINGLE
ELEMENT
100
90
120o
80
70
u = 30o
60o 90o
180o 270o
DC
60
50
0
5
10
15
20
25
30
35
AVERAGE ON-STATE CURRENT, IT(AV),
(AMPERES)
40
maximum allowable value. These
curves have definite end points for
the various conduction angles.
These end points represent the
RMS rating of the device. The
RMS current rating is necessary to
prevent excessive heating of the
resistive elements of the SCR,
such as joints, leads, interfaces,
etc. The relationship between the
RMS value and the average value
of a current waveform is dependent upon the wave shape. For the
data sheet rating standard half
wave sinusoidal waveform, the
ratio of RMS to average values is
1.57. For low duty cycle waveforms, the average value can be
well within device ratings but the
high peak currents can result in
the allowable RMS rating being
exceeded. Similar curves are
provided for rectangular current
waveforms, typical highly inductive
loads.
1.8 POW-R-BLOK™ Rating
Curves
In addition to the standard sine
and square wave information,
there are also families of curves
for assemblies of AC switches,
single and three-phase bridges.
This latter group takes the
designer one step closer in
selecting a heatsink to satisfy his
systems needs.
The set of curves shown in
Figure 1.6 for the single phase AC
switch will be used to demonstrate
how the curves were constructed.
This set of curves is for one (1)
CD43_ _60 module mounted on a
heatsink. The left hand vertical
axis is for total average power, the
right hand vertical is for maximum
allowable case temperature, the
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
Figure 1.6 Maximum Total Power Dissipation and Maximum Ambient Temperature Curve for
AC Switch Application
AC SWITCH
1 CD43_ _60
0.2
0.15
RθCA = oC/W
0.1
0.3
0.05
79
0.4
200
88
0.6
150
98
107
100
1.0
0.8
50
MAXIMUM ALLOWABLE
IRMS
250
CASE TEMPERATURE, (0C)
MAXIMUM TOTAL POWER
DISSIPATION, PTOT, (WATTS)
300
116
0
0
40
80
120
IRMS, (AMPERES)
horizontal axis is split between
current and ambient temperature.
The first step is to plot the left
hand half of the curve. This
information is available from the
more familiar average power
versus average current curve. In
this case, only the 180° sine data
is plotted. First the average current
is changed to RMS by the 2.22
factor. The 2.22 factor takes
current rating from average SCR
current to RMS switch current for
180° sine. Then the average power
for the AC switch is plotted as a
function of RMS switch current.
The formula
TC = Tj – PAVGRu(J-C)
is used to determine the maximum
allowable case temperature while
maintaining the junction temperature rating of 125°C. Three or four
power levels were selected to do
the calculations to determine case
temperature limits. For instance, at
108A RMS, the power dissipation
is 150 watts. Ru(J-C) is determined again from average power
and case temperature curves both
a function of current. The value for
160
0 5
15
35
55
75
95
115
AMBIENT TEMPERATURE, (oC)
PTOT = Total power
dissipation
the CD43_ _60 is 0.183°C/W,
based on the complete module
and 180° sine. This yields
TC = 125°C – 150W x
0.183°C/W
TC = 98°C
A horizontal line is drawn from the
150 watt level and it intersects the
right hand vertical axis at 98°C.
This process is continued until
the maximum allowable case
temperature axis is sufficiently
filled.
The next step is to label the right
hand horizontal axis with ambient
temperatures up to 125°C which
corresponds to the maximum
permitted junction temperature.
The formula
TA = TC – PTOT x Ru(C-A)
is used to generate case-to-ambient thermal impedance lines
where:
TA = Ambient temperature
TC = Maximum allowable
case temperature from
above
NOTE: If 3 modules were used as
in three-phase AC switch, PTOT
would be the total power of all
three modules.
and
Ru(C-A) = Thermal impedance
case-to-ambient.
The procedure is to take an
average power dissipation and its
corresponding maximum allowable
case temperature and arbitrarily
select Ru(c-a) values to calculate
maximum ambients. For example
TA = 98°C – 150W x 0.1°C/W
TA = 83°C
The intersection of the 83°C
ambient and 98°C case
temperature becomes a point on
the 0.1°C/W Ru(C-A) line. The line
may be drawn through this point
and the 125°C ambient which is a
common point to all Ru(C-A) lines.
Another Ru(C-A) is chosen and
the procedure is repeated. If
xix
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
Figure 1.7 Maximum Total Power Dissipation and Maximum Ambient Temperature Curve for
Three-Phase Bridge Application.
3∅-BRIDGE AND AC SWITCH
3 CD43_ _60
800
0.05
IRMS
76
0.1
640
86
0.15
ID
0.2
480
IDC
320
96
0.3
106
160
MAXIMUM ALLOWABLE
RθCA = oC/W
IRMS
CASE TEMPERATURE, (oC)
MAXIMUM TOTAL POWER
DISSIPATION, PTOT, (WATTS)
960
115
0.4
0.8
0.6
0
0
40
80
120
160
IRMS/IDC, (AMPERES)
negative ambients are found,
choose other values of average
power and case temperature and
continue the process until sufficient Ru(c-a) lines are drawn.
xx
15
35
55
75
95
115
AMBIENT TEMPERATURE, (oC)
Ru(S-A) = Ru(C-A) – Ru(C-S)
N
where
Ru(S-A) = Sink-to-ambient
thermal impedance
Ru(C-A) = Case-to-ambient
thermal impedance
1.9 Sample Problem
Assume one is trying to select a
device to use on a 50hp direct
current machine. A current of
90 amperes is required from a
three-phase 480 volt AC line with
the motor running at base speed.
This assumes a 90% efficiency.
Figure 1.7 is very useful in
determining what heatsink rating is
required for a given ambient. A
horizontal line can be drawn from
the 90 amp point on the ID curve.
This line intersects with the
case-to-heatsink curves on the
right hand side of the illustration.
Assuming a 40°C ambient an
interpolation is needed between
the 0.2°C/W and 0.3°C/W Ru(C-A)
lines. This results in an Ru(C-A) of
0.266°C/W. With three (3)
POW-R-BLOK's mounted on a
common heatsink, the following
formula may be used to determine
the actual heatsink rating required.
0 5
Ru(C-S) = Case-to-sink
thermal
impedance for a
module, i.e.
0.1°C/W
and
N = The quantity of
POW-R-BLOK’s on the
common sink.
The sink-to-ambient thermal
impedance is
Ru(S-A) =
0.266°C/W – 0.1°C/W
3
Ru(S-A) = 0.23°C/W
This value of thermal impedance,
however, only guarantees the
junction temperature will not
exceed 125°C. This is not normally
the approach taken by designers.
A safety margin is normally
applied to keep the junction to a
lower value and provide added
system reliability. A simple method
to use with the curves at hand is
to add the desired safety margin
onto the actual maximum ambient.
If 20° margin on junction
temperature is desired in a 40°C
ambient, extend the existing horizontal line so that it intersects with
the vertical 60°C line. This
intersection lies on another
Ru(C-A) line which is 0.2°C/W.
This translates into a 0.17°C/W
heatsink to ambient thermal
impedance. This heatsink would
guarantee that even with worst
case device parameters, the peak
junction temperature will not
exceed 105°C.
Similar problems may be solved
with any of the other sets of
curves for AC switch or single
phase bridge configurations.
1.10 Surge and I2t Ratings
For non-recurrent current
overloads, the rated junction
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
Figure 1.8 di/dt Test Circuit and Waveform
TEST CIRCUIT
WAVEFORM
IT
ITM
ITM
2
L ≈ 1.68
t1
R
AC
Supply
di ITM
=
dt 2t1
t1VDM
ITM
L
DUT
C
C ≈ 5.6
t1ITM
VDM
Trigger
R ≈ 0.54
VDM
ITM
Pulse
Test Parameter
Recommended Values
ITM
≥ Twice Device
Current Rating
≥ Iµs
≥ 60PPS
Maximum Rated Value
Rated Value
20V/20Ω, tr = Iµs, tr = 3µs
≥ 1000 Hours
t1
Test REP Rate
Test Temperature
Off-State Voltage
Gate Trigger Pulse
Test Duration
Time
temperature can be exceeded for
a brief instant as indicated by the
surge and I2t ratings. Nonrecurrent ratings apply only when
they are not repeated before the
peak junction temperature has
returned to its maximum rated
value or less. Non-recurrent
ratings apply to situations that
occur no more than a limited,
typically 100, number of times over
the life of the device. In
determining the surge current
rating, the device is assumed to
be at its rated junction
temperature prior to application
of the overload. Many of the
device parameters are not
specified or guaranteed
immediately following the surge
current. Surge current ratings are
provided for one, three, or ten half
cycles of sinusoidal current at
60 Hz. The I2t rating is derived
from the single cycle surge current
rating. The “I” in I2t rating is the
RMS value of the surge current,
while it is a peak value in the
surge current rating. The I2t rating
is useful in coordinating fuses to
protect the SCR or diode.
1.11 di/dt Ratings
When the rate of rise of anode
current (di/dt) is very rapid
compared to the spreading
velocity of the turn-on process
across the junctions, local “hot
spot” heating will occur. These
“hot spots” may lead to localized
excessive temperatures that can
destroy the device.
The di/dt test circuit and standard
waveform are shown in Figure 1.8.
The di/dt rating guarantees that
the device will block voltage but
does not guarantee maintenance
of device dynamic characteristics
such as turn-off time and dv/dt
capability.
The circuit designer must consider
all current sources when
assessing di/dt. In particular, the
discharge current from a snubber
network must be included in determining the application di/dt.
and its time integral is the
recovered charge, Qrr. Figure 1.9
illustrates a typical reverse
recovery waveform and includes
the definition of reverse recovery
time, trr.
Both Qrr and trr are strongly circuit
dependent as well as device
dependent. The peak on-state
forward current prior to
commutation as well as the
commutation di/dt are significant
circuit variables. Recovered
charge has a positive temperature
coefficient. Diodes are available in
power modules in standard, fast,
and super fast recovery times.
With the exception of the ED
Series, POW-R-BRIK™ and
OPEN-BRIK™ modules, the SCRs
used in POW-R-BLOK™ modules
have standard recovery times
typical of power line frequency
applications.
1.12 Reverse Recovery
Characteristics
1.13 Thermal Resistance
During commutation from forward
conduction to the off-state, SCRs
and diodes display a transient
reverse current that far exceeds
the maximum rated blocking
current. This reverse current is
called reverse recovery current
Temperature calculations are
simplified by using thermal
resistance concepts. The flow of
heat through a thermal path as a
result of power dissipation is
analogous to the flow of current
through a conductive path as a
xxi
Powerex, Inc., 200 Hillis Street, Youngwood, Pennsylvania 15697-1800 (724) 925-7272
SCR/GTO/Diode
POW-R-BLOK™ Modules
Ratings and Characteristics
diR
IF/IT
dt
Time
trr
0
Qrr
I
( 4R (
IR
T0
T1
T2
T3 T4
1.14 Transient Thermal
Impedance
Figure 1.10 Transient Thermal
Impedance
Characteristic
Curve
TRANSIENT THERMAL IMPEDANCE, Zu(J-C)(t), (oC/WATT)
Figure 1.9 Reverse Recovery
Waveform and
Parameter
Definitions
TRANSIENT THERMAL IMPEDANCE
CHARACTERISTICS (JUNCTION-TO-CASE)
0
10
101
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0
10-3
10-2
10-1
100
TIME, t, (SECONDS)
result of a voltage source. Hence,
knowing the power being
dissipated in a device, and the
ambient temperature, the resulting
junction temperature can be calculated using the total thermal resistance and the following equation.
Tj = TA + PT* Ru(J-A)
where:
Ru(J-A) = Total thermal
resistance
junction-to-ambient
(°C/W)
PT = Total power
dissipation (W)
Tj, TA = Junction, ambient
temperature
The total thermal resistance is
given by:
Ru(J-A) = RuJ-C) +
Ru(C-S) + Ru(S-A)
xxii
where:
Ru(J-C) = Junction-to-case
thermal resistance
specified on data
sheet (°C/W)
Ru(C-S) =Lubricated
case-to-sink thermal
resistance specified
on data sheet
(°C/W)
Ru(S-A) = Sink-to-ambient
thermal resistance
(°C/W)
The thermal resistance (Ru(J-C))
specified for a device is always a
maximum value, with a safety
margin included to allow for
production variations from lot to
lot. The interface case-to-sink
thermal resistance (Ru(C-S)) can
be significant and the data sheet
value specified is for a baseplate
properly lubricated with thermal
compound.
For short or low duty cycle power
pulses, using the steady state
thermal resistance will give
conservative junction
temperatures. In addition, using
the average value of power
dissipation will underestimate the
peak junction temperature. The
solution is use of the transient
thermal impedance curves
(Figure 1.10 illustrates a typical
transient thermal impedance
curve). For a power device
subjected to single or very low
duty cycle, short duration power
pulses, the maximum allowable
power dissipation during the
transient period can be
substantially greater than the
steady state dissipation capability.