UC3845AN STMicroelectronics, UC3845AN Datasheet - Page 8

• Manufacturer Part Number: UC3845AN
• Description: IC CURR-MODE PWM CTRLR 8-MINIDIP
• Manufacturer: STMicroelectronics

Specifications of UC3845AN

• Pwm Type: Current Mode
• Number Of Outputs: 1
• Frequency - Max: 500kHz
• Duty Cycle: 50%
• Voltage - Supply: 8.2 V ~ 25 V
• Buck: No
• Boost: Yes
• Flyback: Yes
• Inverting: No
• Doubler: No
• Divider: No
• Cuk: No
• Isolated: Yes
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 8-DIP (0.300", 7.62mm)
• Frequency-max: 500kHz
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 497-3083-5

Figure 15 : Under Voltage Lockout.
UC2842A/3A/4A/5A - UC3842A/3A/4A/5A
Figure 16 : Current Sense Circuit .
Peak current (i
A small RC filter may be required to suppress switch transients.
8/15
Figure 14 : Error Amp Configuration.
I
S max
V
i
1.0 V
R
R
s
S
S
) is determined by the formula
7
I
S
R
C
V
D95IN347
V
Z
OFF
ON
i
ON/OFF COMMAND
CURRENT
TO REST OF IC
SENSE
UC3842A
UC3844A
COMP
GND
16V
10V
Z
f
1
3
5
COMP
UC3843A
UC3845A
8.4V
7.6V
V
FB
ERROR
AMPL.
2
1
2.5V
<0.5mA
<17mA
Fig.15-UC3842A
+
-
I
2R
CC
R
V
OFF
1V
D95IN345
1mA
V
ON
COMPARATOR
CURRENT
SENSE
V
CC