UC3844D Fairchild Semiconductor, UC3844D Datasheet - Page 3

• Manufacturer Part Number: UC3844D
• Description: IC CTLR PWM CURR MODE 14-SOIC
• Manufacturer: Fairchild Semiconductor

Specifications of UC3844D

• Pwm Type: Current Mode
• Number Of Outputs: 1
• Frequency - Max: 500kHz
• Duty Cycle: 50%
• 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: 14-SOIC (3.9mm Width), 14-SOL
• Frequency-max: 500kHz
• Duty Cycle (max): 50 %
• Output Current: 1000 mA
• Mounting Style: SMD/SMT
• Switching Frequency: 500 KHz
• Operating Supply Voltage: 30 V
• Supply Current: 17 mA
• Maximum Operating Temperature: + 70 C
• Fall Time: 35 ns
• Minimum Operating Temperature: 0 C
• Rise Time: 45 ns
• Synchronous Pin: No
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: UC3844DFS

Electrical Characteristics
(V
Parameter
REFERENCE SECTION
Reference Output Voltage
Line Regulation
Load Regulation
Short Circuit Output Current
OSCILLATOR SECTION
Oscillation Frequency
Frequency Change with
Voltage
Oscillator Amplitude
ERROR AMPLIFIER SECTION
Input Bias Current
Input Voltage
Open Loop Voltage Gain
Power Supply Rejection Ratio
Output Sink Current
Output Source Current
High Output Voltage
Low Output Voltage
CURRENT SENSE SECTION
Gain
Maximum Input Signal
Power Supply Rejection Ratio
Input Bias Current
OUTPUT SECTION
Low Output Voltage
High Output Voltage
Rise Time
Fall Time
UNDER-VOLTAGE LOCKOUT SECTION
Start Threshold
Min. Operating Voltage
(After Turn On)
CC
=15V, R
T
=10k , C
T
=3.3nF, T
V
I
A
Symbol
V
SOURCE
V
OPR(MIN)
V
PSRR
PSRR
V
= 0 C to +70 C, unless otherwise specified)
V
f/ V
I
I
I
TH(ST)
I(MAX)
G
V
V
I(E>A)
V
V
V
V
BIAS
SINK
BIAS
I
G
OSC
REF
SC
t
t
OH
OH
REF
REF
VO
OL
OL
f
R
F
V
CC
UC3842/UC3844
UC3843/UC3845
T
12V
1mA
T
T
12V
V
2V
12V
V
V
V
V
(Note 1 & 2)
V
12V
I
I
I
I
T
T
UC3842/UC3844
UC3843/UC3844
SINK
SINK
SOURCE
SOURCE
J
A
J
J
J
pin1
pin2
pin2
pin2
pin2
pin1
= 25 C, I
= 25 C
= 25 C, C
= 25 C, C
= 25 C
V
= 2.5V
= 2.7V, V
= 2.3V, V
= 2.3V, R
= 2.7V, R
= 5V(Note 1)
= 20mA
= 200mA
V
V
V
V
O
I
REF
CC
CC
CC
CC
= 20mA
= 200mA
Conditions
4V (Note3)
REF
L
L
25V
25V
25V (Note3)
25V (Note 1,3)
20mA
= 1nF (Note 3)
= 1nF (Note 3)
pin1
pin1
L
L
-
-
-
= 1mA
= 15k
= 15k
= 5V
= 1.1V
to GND
to Pin 8
Min.
4.90
2.42
2.85
14.5
-0.6
0.9
7.8
8.5
7.0
47
65
60
13
12
2
5
-
-
-
-
-
-
-
-
-
-
-
-
-
UC3842/UC3843/UC3844/UC3845
Typ.
5.00
-100
0.05
2.50
0.08
13.5
13.0
16.0
10.0
-0.1
-1.0
1.6
0.8
1.4
8.4
7.6
52
90
70
70
45
35
-3
6
6
7
6
3
1
Max.
-180
5.10
2.58
3.15
17.5
11.5
150
150
1.1
1.1
-10
0.4
2.2
9.0
8.2
20
25
57
-2
1
-
-
-
-
-
-
-
-
-
V
Unit
kHz
V/V
mV
mV
mA
mA
mA
dB
dB
dB
ns
ns
%
P-P
V
V
V
V
V
V
V
V
V
V
V
V
V
A
A
3