SG3525A
http://onsemi.com
3
MAXIMUM RATINGS
Rating Symbol Value Unit
Supply Voltage V
CC
+40 Vdc
Collector Supply Voltage V
C
+40 Vdc
Logic Inputs −0.3 to +5.5 V
Analog Inputs −0.3 to V
CC
V
Output Current, Source or Sink I
O
±500 mA
Reference Output Current I
ref
50 mA
Oscillator Charging Current 5.0 mA
Power Dissipation
T
A
= +25°C (Note 1)
T
C
= +25°C (Note 2)
P
D
1000
2000
mW
Thermal Resistance, Junction−to−Air R
JA
100 °C/W
Thermal Resistance, Junction−to−Case R
JC
60 °C/W
Operating Junction Temperature T
J
+150 °C
Storage Temperature Range T
stg
−55 to +125 °C
Lead Temperature (Soldering, 10 seconds) T
Solder
+300 °C
Maximum ratings are those values beyond which device damage can occur. Maximum ratings applied to the device are individual stress limit
values (not normal operating conditions) and are not valid simultaneously. If these limits are exceeded, device functional operation is not implied,
damage may occur and reliability may be affected.
1. Derate at 10 mW/°C for ambient temperatures above +50°C.
2. Derate at 16 mW/°C for case temperatures above +25°C.
RECOMMENDED OPERATING CONDITIONS
Characteristics Symbol Min Max Unit
Supply Voltage V
CC
8.0 35 Vdc
Collector Supply Voltage V
C
4.5 35 Vdc
Output Sink/Source Current
(Steady State)
(Peak)
I
O
0
0
±100
±400
mA
Reference Load Current I
ref
0 20 mA
Oscillator Frequency Range f
osc
0.1 400 kHz
Oscillator Timing Resistor R
T
2.0 150 k
Oscillator Timing Capacitor C
T
0.001 0.2 F
Deadtime Resistor Range R
D
0 500
Operating Ambient Temperature Range T
A
0 +70 °C
APPLICATION INFORMATION
Shutdown Options (See Block Diagram, page 2)
Since both the compensation and soft−start terminals
(Pins 9 and 8) have current source pull−ups, either can
readily accept a pull−down signal which only has to sink a
maximum of 100 A to turn off the outputs. This is subject
to the added requirement of discharging whatever external
capacitance may be attached to these pins.
An alternate approach is the use of the shutdown circuitry
of Pin 10 which has been improved to enhance the available
shutdown options. Activating this circuit by applying a
positive signal on Pin 10 performs two functions: the PWM
latch is immediately set providing the fastest turn−off signal
to the outputs; and a 150 A current sink begins to discharge
the external soft−start capacitor. If the shutdown command
is short, the PWM signal is terminated without significant
discharge of the soft−start capacitor, thus, allowing, for
example, a convenient implementation of pulse−by−pulse
current limiting. Holding Pin 10 high for a longer duration,
however, will ultimately discharge this external capacitor,
recycling slow turn−on upon release.
Pin 10 should not be left floating as noise pickup could
conceivably interrupt normal operation.
