UC3843AD Microsemi Analog Mixed Signal Group, UC3843AD Datasheet - Page 6
![no-image](/images/manufacturer_photos/0/4/444/microsemi_analog_mixed_signal_group_sml.jpg)
UC3843AD
Manufacturer Part Number
UC3843AD
Description
IC CTRLR PWM CURRENT MOSE 14SOIC
Manufacturer
Microsemi Analog Mixed Signal Group
Datasheet
1.UC3844AM.pdf
(8 pages)
Specifications of UC3843AD
Pwm Type
Current Mode
Number Of Outputs
1
Frequency - Max
500kHz
Duty Cycle
100%
Voltage - Supply
8.2 V ~ 25 V
Buck
Yes
Boost
Yes
Flyback
Yes
Inverting
No
Doubler
No
Divider
No
Cuk
No
Isolated
Yes
Operating Temperature
0°C ~ 70°C
Package / Case
14-SOIC (3.9mm Width), 14-SOL
Frequency-max
500kHz
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
UC3843ADCT
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
UC3843AD
Manufacturer:
MOTOROLA
Quantity:
43
Company:
Part Number:
UC3843AD
Manufacturer:
MOT
Quantity:
5 510
Part Number:
UC3843AD
Manufacturer:
UC
Quantity:
20 000
Company:
Part Number:
UC3843AD1
Manufacturer:
INTEL
Quantity:
2 944
Part Number:
UC3843AD1013TR
Manufacturer:
ST
Quantity:
20 000
Part Number:
UC3843AD14
Manufacturer:
ST
Quantity:
20 000
Company:
Part Number:
UC3843AD1R2G
Manufacturer:
MITSUBIS
Quantity:
6 219
Company:
Part Number:
UC3843AD2R2G
Manufacturer:
ST
Quantity:
24 194
Part Number:
UC3843AD8
Manufacturer:
TI/德州仪器
Quantity:
20 000
Part Number:
UC3843AD8TR
Manufacturer:
NS/国半
Quantity:
20 000
UC184xA/284xA/384xA
6
The RC low pass filter will eliminate the leading edge current spike
caused by parasitics of Power MOSFET.
UCx84xA
FIGURE 3. — CURRENT SENSE SPIKE SUPPRESSION
7
6
5
3
V
CC
FIGURE 5. — EXTERNAL DUTY CYCLE CLAMP AND MULTI-UNIT SYNCHRONIZATION
CHANGE
f =
f =
C
P R O D U C T D A T A B O O K 1 9 9 6 / 1 9 9 7
R
R
R
(R
A
B
A
DC BUS
A
+ 2R
R
1.44
+ 2R
B
C
T Y P I C A L A P P L I C AT I O N C I R C U I T S
Q1
R
B
U R R E N T
P
S
B
)C
7
6
2
0.01
R O D U C T I O N
Precision duty cycle limiting as well as synchronizing several parts is
possible with the above circuitry.
I
PK(MAX)
8
5
TIMER
=
555
M
1.0V
R
4
I
O D E
S
PK
1
P W M C
UCx84xA devices
3
D
A resistor (R
& ringing caused by the MOSFET input capacitance and any
inductance in series with the gate drive. (Note: It is very important to
have a low inductance ground path to insure correct operation of the
I.C. This can be done by making the ground paths as short and as
wide as possible.)
To other
A T A
O N T R O L L E R
8
4
FIGURE 4. — MOSFET PARASITIC OSCILLATIONS
1
S
) in series with the MOSFET gate will reduce overshoot
H E E T
UCx84xA
UCx84xA
5
5
7
6
V
CC
R
1
DC BUS
Q1
R
S
Copyright © 1995
Rev. 1.2a 10/25