UC3845AD Microsemi Analog Mixed Signal Group, UC3845AD Datasheet - Page 5
UC3845AD
Manufacturer Part Number
UC3845AD
Description
IC CTRLR PWM CURRENT MODE 14SOIC
Manufacturer
Microsemi Analog Mixed Signal Group
Datasheet
1.UC3844AM.pdf
(8 pages)
Specifications of UC3845AD
Pwm Type
Current Mode
Number Of Outputs
1
Frequency - Max
500kHz
Duty Cycle
50%
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
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
UC3845AD1
Manufacturer:
TI
Quantity:
5 162
Part Number:
UC3845AD8TR
Manufacturer:
TI/UNITRODE
Quantity:
20 000
Company:
Part Number:
UC3845AD8TRG4
Manufacturer:
ST
Quantity:
16 109
Company:
Part Number:
UC3845ADM-TR
Manufacturer:
VIA
Quantity:
30
Company:
Part Number:
UC3845ADTR
Manufacturer:
TI
Quantity:
14 698
Copyright © 1995
Rev. 1.2a 10/25
FIGURE 1. — OSCILLATOR FREQUENCY vs. TIMING
100k
10k
1M
0
RESISTOR
300
1.0k
C
T
R
= 4.7nF
T
P R O D U C T D A T A B O O K 1 9 9 6 / 1 9 9 7
- (ohms)
3.0k
FIGURE 2. — MAXIMUM DUTY CYCLE vs. TIMING RESISTOR
100.0
C
80.0
60.0
40.0
20.0
U R R E N T
P
0
10.0k
C
R O D U C T I O N
T
C H A R A C T E R I S T I C C U R V E S
= 1nF
C
T
= 2.2nF
30.0k
300
M
O D E
100k
1.0k
R
T
P W M C
- (ohms)
3.0k
D
Note: Output drive frequency is half the oscillator frequency for
A T A
10.0k
O N T R O L L E R
the UCx844A/5A devices.
UC184xA/284xA/384xA
S
30.0k
H E E T
GROUND
For R
100k
R
T
T
V
/C
> 5k, f
REF
T
8
4
5
1.72
R
T
C
T
R
T
C
T
5