UC3842BVD1G ON Semiconductor, UC3842BVD1G Datasheet - Page 12
UC3842BVD1G
Manufacturer Part Number
UC3842BVD1G
Description
IC CTRLR CURRENT MODE HP 8SOIC
Manufacturer
ON Semiconductor
Datasheet
1.UC3842BDR2G.pdf
(21 pages)
Specifications of UC3842BVD1G
Pwm Type
Current Mode
Number Of Outputs
1
Frequency - Max
275kHz
Duty Cycle
96%
Voltage - Supply
11.5 V ~ 25 V
Buck
No
Boost
Yes
Flyback
Yes
Inverting
No
Doubler
No
Divider
No
Cuk
No
Isolated
Yes
Operating Temperature
-40°C ~ 105°C
Package / Case
8-SOIC (3.9mm Width)
Frequency-max
275kHz
Duty Cycle (max)
96 %
Output Current
1000 mA
Mounting Style
SMD/SMT
Switching Frequency
500 KHz
Maximum Operating Temperature
+ 105 C
Fall Time
50 ns
Minimum Operating Temperature
- 40 C
Rise Time
50 ns
Synchronous Pin
No
Topology
Boost, Flyback, Forward
Number Of Pwm Outputs
1
On/off Pin
No
Adjustable Output
No
Switching Freq
500KHz
Operating Supply Voltage (max)
30V
Operating Temperature Classification
Industrial
Mounting
Surface Mount
Pin Count
8
Package Type
SOIC N
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
UC3842BVD1GOS
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
UC3842BVD1G
Manufacturer:
ON Semiconductor
Quantity:
23
C
-
+
Virtually lossless current sensing can be achieved with the implementation of a
SENSEFET power switch. For proper operation during over-current conditions, a
reduction of the I
1.0M
Figure 26. Current Sensing Power MOSFET
5.0V Ref
8(14)
4(7)
2(3)
1(1)
Comp/Latch
pk(max)
S
R
t
Soft-Start
Q
Figure 24. Soft−Start Circuit
Control Circuitry Ground:
clamp level must be implemented. Refer to Figures 23 and 25.
≈ 3600C in mF
To Pin (9)
EA
+
R
R
-
+
(12)
Osc
1.0mA
Bias
V
(11)
(10)
(8)
(5)
CC
2R
G
R
1/4 W
S
R
-
+
D
M
5(9)
1.0V
SENSEFET
V
in
Then : V Pin 5 [ 0.075 I pk
V Pin 5 [
If: SENSEFET = MTP10N10M
R
5.0V Ref
K
To Input Source
S
S
Power Ground:
= 200
Return
S
R
r DM(on) ) R S
R S I pk r DS(on)
Q
http://onsemi.com
C
12
R
R
2
1
8(14)
t SoftStart + * In 1 *
4(7)
2(3)
1(1)
MPSA63
V Clamp [
Figure 25. Adjustable Buffered Reduction of
Figure 27. Current Waveform Spike Suppression
EA
R
R
-
+
+
R 2
R 1
The addition of the RC filter will eliminate instability caused by the leading
edge spike on the current waveform.
Clamp Level with Soft−Start
Osc
1.67
Bias
1.0 mA
) 1
5.0V Ref
Comp/Latch
3 V Clamp
2R
V C
R
S
R
Where: 0 ≤ V
V
C
Clamp
Q
1.0V
5(9)
R 1 ) R 2
-
+
R 1 R 2
5.0V Ref
Clamp
Comp/Latch
7(12)
≤ 1.0 V
+
-
S
R
V
CC
I pk(max) [
Q
7(11)
6(10)
5(8)
3(5)
+
-
C
R
V Clamp
7(12)
R S
V
CC
V
Q1
R
7(11)
6(10)
5(8)
3(5)
in
S
Q1
V
R
in
S