Apex SA08 Datasheet

MICROTECHNOLOGY
FEATURES
PULSE WIDTH MODULATION AMPLIFIER
SA08
HTTP://WWW.APEXMICROTECH.COM (800) 546-APEX (800) 546-2739
• IGBT OUTPUTS
• WIDE SUPPLY RANGE—16-500V
• 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 oscil­lator frequency by two, which provides the switching fre­quency 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
Vcc
10
+PWM
3 4
CONTROL
SIGNAL
3/7V
FLAG
CLK OUT
CLK IN
GND
470pF
45K
2
1
5
÷2OSC
SA08
USA BeO
TE949311
EXTERNAL CONNECTIONS
ISENSE A
CLK IN
CLK OUT
+PWM
FLAG
GND
1 2 3
TOP
TOP
VIEW
VIEW
4 5 6
ILIM/SHDN
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.
CURRENT LIMIT
PWM
OUTPUT
DRIVERS
SHUTDOWN
CONTROL
9
+V
S
B OUT
8
11
A OUT
I SENSE A
12
6
ILIM/SHDN
7
I SENSE B RSENSE
.1µF
12 11 10
9 8 7
*
A OUT
*
VCC
+VS
B OUT I SENSE B
MOTOR
5K
5K
RSENSE
5K
5V
5V
APEX MICROTECHNOLOGY CORPORATION • TELEPHONE (520) 690-8600 • FAX (520) 888-3329 • ORDERS (520) 690-8601 • EMAIL prodlit@apexmicrotech.com
SA08
ABSOLUTE MAXIMUM RATINGS
SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
SUPPLY VOLTAGE, +V SUPPLY VOLTAGE, V POWER DISSIPATION, internal TEMPERATURE, pin solder - 10s 300°C TEMPERATURE, junction
S
CC
1
2
500V 16V 250W
150°C TEMPERATURE, storage –65 to +150°C OPERATING TEMPERATURE RANGE, case –55 to +125°C INPUT VOLTAGE, +PWM 0 TO +11V
SPECIFICATIONS
INPUT VOLTAGE, I
PARAMETER TEST CONDITIONS
LIM
2
MIN TYP MAX UNITS
0 TO +10V
CLOCK (CLK)
CLK OUT, high level CLK OUT, low level CLK IN, low level CLK IN, high level
4
4
4
4
I
1mA 4.8 5.3 V
OUT
I
1mA 0 .4 V
OUT
0.9V
3.7 5.4 V
FREQUENCY 44.10 45.00 46.90 kHz
ANALOG INPUT (+PWM)
center voltage 5V P-P voltage 0/100% modulation 4 V
FLAG
FLAG, high level 10 V FLAG, low level 0V
OUTPUT
TOTAL DROP I = 20A 5.4 V EFFICIENCY, 20A output VS = 380V 98 % SWITCHING FREQUENCY OSC in ÷ 2 22.05 22.50 22.95 kHz CURRENT, continuous CURRENT, peak
4
4
100°C case 20 A
28 A
POWER SUPPLY
VOLTAGE, V VOLTAGE, V CURRENT, V CURRENT, V CURRENT, V
I
/SHUTDOWN
LIM
S CC
CC
shutdown 50 mA
CC, S
Full temperature range 16 Full temperature range 14 15 16 V I
= 0 80 mA
OUT
No Load 90 mA
5
240 500 V
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
NOTES: 1. Each of the two active output transistors can dissipate 125W.
2. Unless otherwise noted: TC = 25°C, VS, VCC 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
CAUTION
The SA08 is constructed from static sensitive components. ESD handling procedures must be observed.
S(MIN)
= 0V.
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.
APEX MICROTECHNOLOGY CORPORATION • 5980 NORTH SHANNON ROAD • TUCSON, ARIZONA 85741 • USA • APPLICATIONS HOTLINE: 1 (800) 546-2739
APEX MICROTECHNOLOGY CORPORATION • 5980 NORTH SHANNON ROAD • TUCSON, ARIZONA 85741 • USA • APPLICATIONS HOTLINE: 1 (800) 546-2739
TYPICAL PERFORMANCE GRAPHS
SA08
125
POWER DERATING
100
75
50
25
EACH ACTIVE
OUTPUT TRANSISTOR
0
INTERNAL POWER DISSIPATION, (W)
0 75 100
25 50 125
CASE TEMPERATURE, (°C)
20
16
12
8
4
FORWARD CURRENT, (A)
0
DIODE FORWARD VOLTAGE DROP, (V)
REVERSE DIODE
Tc = 100°C Tc = 25°C
1.0 1.5 2.0 3.02.5
0.5
100
CLOCK LOADING
99
98
97
96
NORMALIZED FREQUENCY, (%)
95
CLOCK LOAD RESISTANCE, ()
6
CASE TEMPERATURE
5
4
3
2
TOTAL VOLTAGE DROP, (V)
048121620
F NOMINAL = 45kHz
10K
TOTAL VOLTAGE DROP
100°C
OUTPUT CURRENT, I(A)
25°C
CLOCK FREQUENCY OVER TEMP
102.0
101.5
101.0
100.5 100
99.5
99.0
98.5
NORMALIZED FREQUENCY, (%)
98.0 –50
1M100K
–25 0 25 50 75 100 125
CASE TEMPERATURE, (°C)
CONTINUOUS AMPS
20
18
16
14
12
CONTINUOUS AMPS, (A)
10
25 50 75 100 125
CASE TEMPERATURE, (°C)
Vcc QUIESCENT CURRENT
115 110 105 100
NORMALIZED Vcc QUIESCENT CURRENT, (%)
Vcc = 15V F = 22.5 kHz
NORMAL OPERATION
95 90 85
80
–50 –25 0 25 50 75 100 125
CASE TEMPERATURE, (°C)
SHUTDOWN OPERATION
DUTY CYCLE VS ANALOG INPUT
100
B OUT
80
60
40
DUTY CYCLE, (%)
20
A OUT
0
35476
ANALOG INPUT, (V)
Vs QUIESCENT VS VOLTAGE
150
125
100
75
50
0 100 200 300 400 500
NORMALIZED Vs QUIESCENT CURRENT, (%)
Vs, (V)
Vcc QUIESCENT CURRENT
100
96
92
88
84
5
NORMALIZED QUIESCENT CURRENT, (%)
SWITCHING FREQUENCY, F (kHz)
Vs QUIESCENT VS FREQUENCY
100
90
80
70
60
50
525
10 15 20
SWITCHING FREQUENCY, F (kHz)
NORMALIZED Vs QUIESCENT CURRENT, (%)
2510 15 20
APEX MICROTECHNOLOGY CORPORATION • TELEPHONE (520) 690-8600 • FAX (520) 888-3329 • ORDERS (520) 690-8601 • EMAIL prodlit@apexmicrotech.com
OPERATING CONSIDERATIONS
SA08
GENERAL
Helpful information about power supplies, heatsinking and mounting can be found in the “General Operating Consider­ations” section of the Apex data book. For information on the package outline, heatsinks, and mounting hardware see the “Package Outlines” and “Accessories” section of the data book. Also see Application Note 30 on “PWM Basics.”
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 PRO­TECTION 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 tempera­ture 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 transis­tors. The latched condition can be cleared by either recycling
power or by toggling the I LIMIT/SHDN input with a 10V
the V
cc
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 connec­tion (see figures A and B). It is recommended that R 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 network and shutdown divider resistor) and connect the R
LIMIT
re­sistors directly to the GND pin.
resistors (through the filter
LIMIT
I SENSE A
R
I SENSE B
LIMIT
Switching noise spikes will invariably be found at the I SENSE pins. The noise spikes could trip the current
I LIMIT/SHDN
R
FILTER
C
FILTER
5K
IN4148
limit threshold which is only 100 mV. R
FIGURE A. CURRENT LIMIT WITH
FILTER
SHUTDOWN VOLTAGE MODE.
LIMIT
SHUTDOWN
SIGNAL
0/10V
I SENSE A
I SENSE B
R
LIMIT
I LIMIT/SHDN
R
FILTER
C
R
FILTER
5K
LIMIT
5K
SHUTDOWN
SIGNAL
IN4148
and C be adjusted so as to reduce the switching noise
well below 100 mV to prevent false cur­rent limiting. The sum of the DC level plus the noise peak will determine the current limiting
0/10V
value. As in most switching circuits it
FILTER
should
may be difficult to
FIGURE B. CURRENT LIMIT WITH SHUTDOWN CURRENT MODE.
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 starting values are C
The required value of R
LIMIT
= .1uF, R
FILTER
in voltage mode may be calcu-
FILTER
= 5k .
lated by:
R where R
= .1 V / I
LIMIT
is the required resistor value, and I
LIMIT
LIMIT
LIMIT
is the maximum desired current. In current mode the required value of each R divided down by 2 (see Figure B). If R
is 2 times this value since the sense voltage is
LIMIT
is used it will further
SHDN
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 1µF ceramic capacitor in parallel with another low ESR capacitor of at least 10µF per amp of output current. Capacitor types rated for switching applications are the only types that should be consid­ered. 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 .1µF to .47µF 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 condi­tion. 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.
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. A MAY 1999 © 1999 Apex Microtechnology Corp.
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