KA3842B Fairchild Semiconductor, KA3842B Datasheet - Page 4

• Manufacturer Part Number: KA3842B
• Description: IC CONTROLLER PWM SMPS 8-DIP
• Manufacturer: Fairchild Semiconductor

Specifications of KA3842B

• Pwm Type: Current Mode
• Number Of Outputs: 1
• Frequency - Max: 500kHz
• Duty Cycle: 100%
• Voltage - Supply: 11.5 V ~ 30 V
• Buck: No
• Boost: No
• Flyback: No
• Inverting: No
• Doubler: No
• Divider: No
• Cuk: No
• Isolated: No
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 8-DIP (0.300", 7.62mm)
• Frequency-max: 500kHz
• Duty Cycle (max): 100 %
• Output Current: +/- 1 A
• Mounting Style: Through Hole
• Switching Frequency: 500 KHz
• Supply Current: 17 mA
• Maximum Operating Temperature: 150 C
• Fall Time: 35 ns
• Minimum Operating Temperature: - 65 C
• Rise Time: 45 ns
• Synchronous Pin: No
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

KA3842B/KA3843B/KA3844B/KA3845B
Electrical Characteristics
(V
Adjust V
Note:
1. Parameter measured at trip point of latch
2. Gain defined as:
3. These parameters, although guaranteed, are not 100 tested in production.
High peak currents associated with capacitive loads necessitate careful grounding techniques Timing and bypass capacitors
should be connected close to pin 5 in a single point ground. The transistor and 5K potentiometer are used to sample the
oscillator waveform and apply an adjustable ramp to pin 3.
4
A
Parameter
PWM SECTION
Max. Duty Cycle
Min. Duty Cycle
TOTAL STANDBY CURRENT
Start-Up Current
Operating Supply Current
Zener Voltage
CC
=
=15V, R
----------------- -
V
V
pin1
pin3
CC
above the start threshould before setting at 15V
T
,0
=10K , C
V
pin3
T
=3.3nF, T
0.8V
A
= 0 C to +70 C unless otherwise specified)
I
Symbol
CC(OPR)
D
D
D
(Continued)
(MAX)
(Max)
(MIN)
I
V
ST
Figure 1. Open Loop Test Circuit
Z
KA3842B/KA3843B
KA3844B/KA3845B
V
I
CC
pin3
= 25mA
=V
pin2
Conditions
=ON
-
-
Min.
95
47
30
-
-
-
Typ.
0.45
97
48
14
38
-
Max.
100
50
17
0
1
-
Unit
mA
mA
%
%
%
V