KA3843AC [FAIRCHILD]
SMPS Controller; SMPS控制器
| 型号： | KA3843AC |
| 厂家： | 
FAIRCHILD SEMICONDUCTOR |
| 描述： | SMPS Controller |
| 文件： | 总6页 (文件大小：50K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
www.fairchildsemi.com
KA3843AC
SMPS Controller
Features
Description
• Low start current 0.2mA (typ)
• Operating range up to 500kHz
• Cycle by cycle current limiting
• Under voltage lock out with hysteresis
• Short shutdown delay time: typ.100ns
• High current totem-pole output
• Output swing limiting: 22V
The KA3843AC are fixed PWM controller for Off-Line and
DC to DC converter applications. The internal circuits
include UVLO, low start up current circuit, temperature
compensated reference, high gain error amplifier, current
sensing comparator, and high current totem-pole output for
driving a POWER MOSFET. Also KA3843AC provide low
start up current below 0.3mA and short shutdown delay
time typ. 100ns. The KA3843AC is 8.4V(on) and 7.6V(off).
The KA3843AC can operate within 100% duty cycle.
8-DIP
1
8-SOP
1
Internal Block Diagram
7
5
V
CC
29V
5V
SET/
RESET
VREF
8
V
REF
GND
UVLO
Internal
Bias
Good LOGIC
PWR
7
6
5
VC
1/2VREF
C.S
Comp.
PWM
Error Amp
+
-
LATCH
1/3
1V
VFB
2
R
S
22V
OUTPUT
1
3
COMP
C.S
PWR
GND
T
R
T/C
T
OSCILLATOR
4
Rev. 1.0.1
©2005 Fairchild Semiconductor Corporation
KA3843AC
Absolute Maximum Ratings
Parameter
Symbol
Value
Unit
V
Supply voltage
V
30
CC
Output current
I
+1
A
O
Analog inputs (pin2, 3)
Error amp. output sink current
Power dissipation
V
-0.3 to 6.3
V
I(ANA)
I
10
1
mA
W
SINK(EA)
P
D
Electrical Characteristics
(V
CC
= 15V, R = 10KW, C = 3.3nF, T = 0°C to +70°C ,Unless otherwise specified)
T
T
A
Parameter
Symbol
Conditions
Min. Typ. Max. Unit
REFERENCE SECTION
Output voltage
V
T = 25°C, I = 1mA
4.9
5.0
6
5.1
20
25
V
REF
J
O
Line regulation
R
V
= 12V to 25V
CC
-
-
-
mV
mV
Line
Load regulation
Output short circuit
OSILLATOR SECTION
Initial accuracy
R
I
= 1mA to 20mA
O
6
LOAD
I
T = 25°C
a
-100 -180 mA
SC
F
OSC
T = 25°C
J
47
-
52
0.2
1.7
8.3
57
1
kHz
%
Voltage stability
Amplitude
ST
V
V
= 12V to 25V
CC
V
V
, peak to peak
-
-
V
OSC
PIN4
Discharge current
I
T = 25°C
J
7.8
8.8
mA
DISCHG
CURRENT SENSE SECTION
Gain
G
(Note2, 3)
2.85
3
3.15 V/V
V
Maximum input signal
PSRR
V
V
V
V
V
= 5V(Note2)
PIN1
0.9
1.0
70
-2
1.1
-
V
I(MAX)
PSRR
= 12V to 25V (Note1, 2)
-
-
-
dB
uA
ns
CC
Input bias current
Delay to output
I
=0V
-10
BIAS
SENSE
T
D
= 0 V to 2V (Note1)
PIN3
100 200
Notes:
1. These parameters, although guaranteed, are not 100% tested in production.
2. Parameter measured at trip point of latch with V = 0V.
FB
∆VCOMP
------------------------
;O ≤ VSENSE ≤ 0.8V
3. Gain defined as: GV
=
∆VSENSE
2
KA3843AC
Electrical Characteristics (Continued)
(V
CC
= 15V, R = 10KW, C = 3.3nF, T = 0°C to +70°C, Unless otherwise specified)
T
T
A
Parameter
Symbol
Conditions
Min. Typ. Max. Unit
ERROR AMPLIFIER SECTION
Input voltage
V
V
V
V
= 2.5V
2.42 2.50 2.58
V
uA
I
PIN1
Input bias current
Open loop gain
I
=0V
-
-0.3
90
1
- 2
BIAS
FB
= 2V to 4V (Note1)
O
G
VO
65
0.7
60
2
-
-
-
-
-
dB
Unity gain bandwidth
PSRR
GBW
T = 25°C (Note1)
J
MHz
dB
PSRR
V
V
V
V
= 12V to 25V (Note1)
70
6
CC
Output sink current
Output source current
I
= 2.7V, V
= 2.3V, V
= 2.3V
= 1.1V
= 5.0V
mA
mA
SINK
PIN2
PIN2
PIN2
PIN1
PIN1
I
-0.5
-0.8
SOURCE
Output high voltage
V
5
-
6
-
V
V
OH
R1 = 15KΩ to GND
V
= 2.7V
PIN2
R1 = 15kΩ to Vref
Output low voltage
V
0.7
1.1
OL
OUTPUT SECTION
I
I
I
I
= 20mA
-
-
0.1
1.5
13.5
13.5
40
0.4
2.2
-
V
V
SINK
SINK
Output Low Level
Output high level
V
OL
= 200mA
= 20mA
13
12
-
V
SOURCE
SOURCE
V
OH
= 200mA
-
V
Rise time
t
T = 25°C, C1 = 1nF (Note1)
100
100
-
ns
ns
V
R
J
Fall time
t
T = 25°C, C1 = 1nF (Note1)
-
40
F
J
Output voltage swing limit
V
OLIM
V
= 27V, C1 = 1nF
-
22
CC
UNDER VOLTAGE LOCKOUT SECTION
KA3882E
KA3883E
KA3882E
KA3883E
15
7.8
9
16
8.4
10
17
9.0
11
V
V
V
V
Start threshold
V
TH
Min. operating voltage
( after turn on )
V
TL
7.0
7.6
8.2
PWM SECTION
Maximum duty cycle
Minimum duty cycle
TOTAL STANDBY CURRENT
Start-up current
D
KA3882E/KA3883E
-
94
-
96
-
100
0
%
%
MAX
D
MIN
I
-
-
-
-
0.2
11
0.4
17
-
mA
mA
V
ST
Operating supply current
I
V
= V
= 0V
PIN3
CC
PIN2
I = 25mA
CC
V
zener voltage
V
29
CC
Z
* Adjust V
above the start threshold before setting at 15V
CC
Notes :
1. These parameters, although guaranteed, are not 100% tested in production.
2. Parameter measured at trip point of latch with V = 0V.
FB
∆VCOMP
------------------------
;O ≤ VSENSE ≤ 0.8V
3. Gain defined as: GV
=
∆VSENSE
3
KA3843AC
Mechanical Dimensions
Package
Dimensions in millimeters
8-DIP
6.40 ±0.20
0.252 ±0.008
#1
#4
#8
#5
3.30 ±0.30
0.130 ±0.012
5.08
0.200
MAX
7.62
0.300
3.40 ±0.20
0.134 ±0.008
0.33
MIN
0.013
4
KA3843AC
Mechanical Dimensions (Continued)
Package
Dimensions in millimeters
8-SOP
5
KA3843AC
Ordering Information
Product Number
KA3843AC
Package
Operating Temperature
8-DIP
0 ~ +70°C
KA3843ACD
8-SOP
DISCLAIMER
FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY
PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY
LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER
DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS.
LIFE SUPPORT POLICY
FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES
OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR
CORPORATION. As used herein:
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the body,
or (b) support or sustain life, and (c) whose failure to
perform when properly used in accordance with
instructions for use provided in the labeling, can be
reasonably expected to result in a significant injury of the
user.
2. A critical component in any component of a life support
device or system whose failure to perform can be
reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
www.fairchildsemi.com
3/2/05 0.0m 001
Stock#DSxxxxxxxx
” 2005 Fairchild Semiconductor Corporation
相关型号：
KA3843BDT&R
Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, PDSO14, 0.225 INCH, SOP-14
FAIRCHILD
KA3843BDTF
Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BIPolar, PDSO14, SOP-14
FAIRCHILD
©2020 ICPDF网 联系我们和版权申明