APEX MICROTECHNOLOGY CORPORATION TELEPHONE (520) 690-8600 FAX (520) 888-3329 ORDERS (520) 690-8601 EMAIL prodlit@apexmicrotech.com
SA08
USA
BeO
TE949311
FEATURES
IGBT OUTPUTS
WIDE SUPPLY RANGE--16-500V
20A TO 100
C CASE
3 PROTECTION CIRCUITS
SYNCHRONIZED OR EXTERNAL OSCILLATOR
FLEXIBLE FREQUENCY CONTROL
APPLICATIONS
MOTORS
REACTIVE LOADS
MAGNETIC BEARINGS
LARGE PIEZO ELEMENTS
OFF-LINE DRIVERS
C-D WELD CONTROLLER
DESCRIPTION
The SA08 is a pulse width modulation amplifier that can
supply 10KW to the load. An internal oscillator requires no
external components. The clock input stage divides the oscil-
lator frequency by two, which provides the switching fre-
quency of 22.5 kHz. The oscillator may also be used to
synchronize multiple amplifiers. Current sensing is provided
for each half of the bridge giving amplitude and direction data.
A shutdown input turns off all four drivers of the H-bridge
output. A high side current limit and the programmable low
side current limit protect the amplifier from shorts to supply or
ground in addition to load shorts. The H-bridge output IGBTs
are protected from thermal overloads by directly sensing the
temperature of the die. The 12-pin hermetic MO-127 power
package occupies only 3 square inches of board space.
BLOCK DIAGRAM AND TYPICAL APPLICATION
MOTOR TORQUE CONTROL
EXTERNAL CONNECTIONS
TOP
VIEW
CLK IN
CLK OUT
+PWM
FLAG
GND
ILIM/SHDN
ISENSE A
A OUT
+VS
VCC
*
*
B OUT
I SENSE B
1
2
3
4
5
6
12
11
10
9
8
7
TOP
VIEW
Case tied to pin 5. Allow no current in case. Bypassing of supplies
is required. Package is Apex MO-127 (STD). See Outline
Dimensions/Packages in Apex data book.
*See text. As +PWM goes more positive, A OUT duty cycle
increases.
H T T P : / / W W W . A P E X M I C R O T E C H . C O M ( 8 0 0 ) 5 4 6 - A P E X ( 8 0 0 ) 5 4 6 - 2 7 3 9
M I C R O T E C H N O L O G Y
PULSE WIDTH MODULATION AMPLIFIER
SA08
+V
S
A OUT
B OUT
ILIM/SHDN
I SENSE A
I SENSE B
RSENSE
RSENSE
MOTOR
GND
CLK IN
CONTROL
SIGNAL
CLK OUT
PWM/RAMP
+PWM
Vcc
5V
5V
SHUTDOWN
CONTROL
OUTPUT
DRIVERS
PWM
45K
1K
1K
5K
.01
F
470pF
2
OSC
CURRENT
LIMIT
9
8
3
10
4
2
1
5
11
12
6
7
APEX MICROTECHNOLOGY CORPORATION 5980 NORTH SHANNON ROAD TUCSON, ARIZONA 85741 USA APPLICATIONS HOTLINE: 1 (800) 546-2739
PARAMETER
TEST CONDITIONS
2
MIN
TYP
MAX
UNITS
CLOCK (CLK)
CLK OUT, high level
4
I
OUT
1mA
4.8
5.3
V
CLK OUT, low level
4
I
OUT
1mA
0
.4
V
CLK IN, low level
4
0
.9
V
CLK IN, high level
4
3.7
5.4
V
FREQUENCY
44.10
45.00
46.90
kHz
ANALOG INPUT (+PWM)
center voltage
5
V
P-P voltage
0/100% modulation
4
V
FLAG
FLAG, high level
10
V
FLAG, low level
0
V
OUTPUT
TOTAL DROP
I = 20A
5.4
V
EFFICIENCY, 20A output
V
S
= 380V
98
%
SWITCHING FREQUENCY
OSC in
2
22.05
22.50
22.95
kHz
CURRENT, continuous
4
100
C case
20
A
CURRENT, peak
4
28
A
POWER SUPPLY
VOLTAGE, V
S
Full temperature range
16
5
240
500
V
VOLTAGE, V
CC
Full temperature range
14
15
16
V
CURRENT, V
CC
I
OUT
= 0
80
mA
CURRENT, V
CC,
shutdown
50
mA
CURRENT, V
S
No Load
90
mA
I
LIM
/SHUTDOWN
TRIP POINT
90
110
mV
INPUT CURRENT
100
nA
THERMAL
3
RESISTANCE, junction to case
Full temperature range, for each die
1
C/W
RESISTANCE, junction to air
Full temperature range
12
C/W
TEMPERATURE RANGE, case
Meets full range specifications
25
+85
C
ABSOLUTE MAXIMUM RATINGS
SPECIFICATIONS
SA08
ABSOLUTE MAXIMUM RATINGS
SUPPLY VOLTAGE, +V
S
500V
SUPPLY VOLTAGE, V
CC
16V
POWER DISSIPATION, internal
1
250W
TEMPERATURE, pin solder - 10s
300
C
TEMPERATURE, junction
2
150
C
TEMPERATURE, storage
65 to +150
C
OPERATING TEMPERATURE RANGE, case
55 to +125
C
INPUT VOLTAGE, +PWM
0 TO +11V
INPUT VOLTAGE, I
LIM
0 TO +10V
The SA08 is constructed from static sensitive components. ESD handling procedures must be observed.
The internal substrate contains beryllia (BeO). Do not break the seal. If accidentally broken, do not crush,
machine, or subject to temperatures in excess of 850
C to avoid generating toxic fumes.
CAUTION
NOTES: 1.
Each of the two active output transistors can dissipate 125W.
2.
Unless otherwise noted: T
C
= 25
C, V
S
, V
CC
at typical specification.
3.
Long term operation at the maximum junction temperature will result in reduced product life. Derate internal power
dissipation to achieve high MTTF. For guidance, refer to the heatsink data sheet.
4.
Guaranteed but not tested.
5.
If 100% duty cycle is not required V
S(MIN)
= 0V.
SPECIFICATIONS
APEX MICROTECHNOLOGY CORPORATION 5980 NORTH SHANNON ROAD TUCSON, ARIZONA 85741 USA APPLICATIONS HOTLINE: 1 (800) 546-2739
APEX MICROTECHNOLOGY CORPORATION TELEPHONE (520) 690-8600 FAX (520) 888-3329 ORDERS (520) 690-8601 EMAIL prodlit@apexmicrotech.com
TYPICAL PERFORMANCE
GRAPHS
SA08
50 25
0
25
50
75
100 125
80
85
90
95
100
105
110
115
1M
100K
95
98
99
100
CLOCK LOADING
96
97
10K
NORMALIZED FREQUENCY, (%)
CASE TEMPERATURE, (
C)
CLOCK LOAD RESISTANCE, (
)
DUTY CYCLE VS ANALOG INPUT
DUTY CYCLE, (%)
0
20
40
60
80
100
ANALOG INPUT, (V)
3
5
4
7
6
Vcc QUIESCENT CURRENT
NORMALIZED Vcc QUIESCENT CURRENT, (%)
A OUT
B OUT
F NOMINAL = 45kHz
Vcc = 15V
F = 22.5 kHz
NORMAL
OPERATION
SHUTDOWN
OPERATION
50
CASE TEMPERATURE, (
C)
CLOCK FREQUENCY OVER TEMP
NORMALIZED FREQUENCY, (%)
25
0
25
50
75 100 125
98.0
98.5
99.0
99.5
100
100.5
101.0
101.5
102.0
Vcc QUIESCENT CURRENT
NORMALIZED QUIESCENT CURRENT, (%)
0.5
DIODE FORWARD VOLTAGE DROP, (V)
REVERSE DIODE
FORWARD CURRENT, (A)
25
50
75
100
125
14
16
18
20
CONTINUOUS AMPS
12
1.0
1.5
2.0
3.0
2.5
5
0
100
200
300
400
500
25
10
15
20
CASE TEMPERATURE, (
C)
CONTINUOUS AMPS, (A)
10
0
75
100
CASE TEMPERATURE, (
C)
0
POWER DERATING
25
50
125
25
50
75
100
125
INTERNAL POWER DISSIPATION, (W)
SWITCHING FREQUENCY, F (kHz)
Vs, (V)
84
88
92
96
100
50
75
100
125
150
Vs QUIESCENT VS VOLTAGE
5
25
SWITCHING FREQUENCY, F (kHz)
60
70
50
80
90
Vs QUIESCENT VS FREQUENCY
NORMALIZED Vs QUIESCENT CURRENT, (%)
NORMALIZED Vs QUIESCENT CURRENT, (%)
100
10
15
20
EACH ACTIVE
OUTPUT TRANSISTOR
0
4
8
12
16
20
OUTPUT CURRENT, I(A)
2
3
4
5
6
TOTAL VOLTAGE DROP
TOTAL VOLTAGE DROP, (V)
100
C
Tc = 100
C
Tc = 25
C
25
C
CASE TEMPERATURE
20
0
4
8
12
16
This data sheet has been carefully checked and is believed to be reliable, however, no responsibility is assumed for possible inaccuracies or omissions. All specifications are subject to change without notice.
SA08U REV. B MARCH 2001
2001 Apex Microtechnology Corp.
limit threshold
which is only 100
mV. R
FILTER
and
C
FILTER
should be
adjusted so as to
reduce the switch-
ing noise well be-
low 100 mV to pre-
vent false current
limiting. The sum of
the DC level plus
the noise peak will
determine the cur-
rent limiting value.
As in most switch-
ing circuits it may
be difficult to determine the true noise amplitude without
careful attention to grounding of the oscilloscope probe. Use
the shortest possible ground lead for the probe and connect
exactly at the GND terminal of the amplifier. Suggested start-
ing values are C
FILTER
= .1uF, R
FILTER
= 5k .
The required value of R
LIMIT
in voltage mode may be calcu-
lated by:
R
LIMIT
= .1 V / I
LIMIT
where R
LIMIT
is the required resistor value, and I
LIMIT
is the
maximum desired current. In current mode the required value
of each R
LIMIT
is 2 times this value since the sense voltage is
divided down by 2 (see Figure B). If R
SHDN
is used it will further
divide down the sense voltage. The shutdown divider network
will also have an effect on the filtering circuit.
BYPASSING
Adequate bypassing of the power supplies is required for
proper operation. Failure to do so can cause erratic and low
efficiency operation as well as excessive ringing at the outputs.
The Vs supply should be bypassed with at least a 1
F ceramic
capacitor in parallel with another low ESR capacitor of at least
10
F per amp of output current. Capacitor types rated for
switching applications are the only types that should be consid-
ered. The bypass capacitors must be physically connected
directly to the power supply pins. Even one inch of lead length
will cause excessive ringing at the outputs. This is due to the
very fast switching times and the inductance of the lead
connection. The bypassing requirements of the Vcc supply are
less stringent, but still necessary. A .1
F to .47
F ceramic
capacitor connected directly to the Vcc pin will suffice.
STARTUP CONDITIONS
The high side of the IGBT output bridge circuit is driven by
bootstrap circuit and charge pump arrangement. In order for
the circuit to produce a 100% duty cycle indefinitely the low
side of each half bridge circuit must have previously been in the
ON condition. This means, in turn, that if the input signal to the
SA08 at startup is demanding a 100% duty cycle, the output
may not follow the command and may be in a tri-state condi-
tion. The ramp signal must cross the input signal at some point
to correctly determine the output state. After the ramp crosses
the input signal level one time, the output state will be correct
thereafter.
OPERATING
CONSIDERATIONS
SA08
GENERAL
Please read Application Note 30 on "PWM Basics". Refer to
Application Note 1 "General Operating Considerations" for
helpful information regarding power supplies, heat sinking and
mounting. Visit www.apexmicrotech.com for design tools that
help automate pwm filter design; heat sink selection; Apex's
complete Application Notes library; Technical Seminar Work-
book; and Evaluation Kits.
CLOCK CIRCUIT AND RAMP GENERATOR
The clock frequency is internally set to a frequency of
approximately 45kHz. The CLK OUT pin will normally be tied
to the CLK IN pin. The clock is divided by two and applied to an
RC network which produces a ramp signal. An external clock
signal can be applied to the CLK IN pin for synchronization
purposes, but must be 45 kHz +/- 2%.
FLAG OUTPUT
Whenever the SA08 has detected a fault condition, the flag
output is set high (10V). When the programmable low side
current limit is exceeded, the FLAG output will be set high. The
FLAG output will be reset low on the next clock cycle. This
reflects the pulse-by-pulse current limiting feature. When the
internally-set high side current limit is tripped or the thermal
limit is reached, the FLAG output is latched high. See PRO-
TECTION CIRCUITS below.
PROTECTION CIRCUITS
A fixed internal current limit senses the high side current.
Should either of the outputs be shorted to ground the high side
current limit will latch off the output transistors. The tempera-
ture of the output transistors is also monitored. Should a fault
condition raise the temperature of the output transistors to
165
C the thermal protection circuit latch off the output transis-
tors. The latched condition can be cleared by either recycling
the V
cc
power or by toggling the I LIMIT/SHDN input with a 10V
pulse. See Figures A and B. The outputs will remain off as long
as the shutdown pulse is high (10V).
CURRENT LIMIT
There are two load current sensing pins, I SENSE A and I
SENSE B. The two pins can be shorted in the voltage mode
connection but both must be used in the current mode connec-
tion (see figures A and B). It is recommended that R
LIMIT
resistors be non-inductive. Load current flows in the I SENSE
pins. To avoid errors due to lead lengths connect the I LIMIT/
SHDN pin directly to
the R
LIMIT
resistors
(through the filter net-
work and shutdown di-
vider resistor) and con-
nect the R
LIMIT
resistors
directly to the GND pin.
Switching noise
spikes will invariably be
found at the I SENSE
pins. The noise spikes
could trip the current
I SENSE A
I SENSE B
I LIMIT/SHDN
R
FILTER
C
FILTER
R
LIMIT
IN4148
SHUTDOWN
SIGNAL
5K
FIGURE A. CURRENT LIMIT WITH
SHUTDOWN VOLTAGE MODE.
0/10V
I SENSE A
I SENSE B
I LIMIT/SHDN
R
FILTER
C
FILTER
IN4148
0/10V
SHUTDOWN
SIGNAL
5K
5K
FIGURE B. CURRENT LIMIT WITH
SHUTDOWN CURRENT MODE.
R
LIMIT
R
LIMIT
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