UC3844 Datasheet PDF - SYC
Part Number | UC3844 | |
Description | SMPS Controller | |
Manufacturers | SYC | |
Logo | ||
There is a preview and UC3844 download ( pdf file ) link at the bottom of this page. Total 11 Pages |
Preview 1 page No Preview Available ! UC3842/UC3843/UC3844/UC3845
SMPS Controller
Features
• Low Start up Current
• Maximum Duty Clamp
• UVLO With Hysteresis
• Operating Frequency up to 500KHz
Internal Block Diagram
Description
The UC3842/UC3843/UC3844/UC3845 are fixed
frequencycurrent-mode PWM controller. They are specially
designed for Off-Line and DC to DC converter applications
with minimum external components. These integrated
circuits feature a trimmed oscillator for precise duty cycle
control, a temperature compensated reference, high gain
error amplifier, current sensing comparator and a high
current totempole output for driving a Power MOSFET. The
UC3842 and UC3844 have UVLO thresholds of 16V (on)
and 10V (off). The UC3843 and UC3845 are 8.5V(on) and
7.9V (off). The UC3842 and UC3843 can operate within
100% duty cycle. The UC3844 and UC3845 can operate
with 50% duty cycle.
8-DIP
8-SOP
1
14-SOP
1
1
* NORMALLY 8DIP/8SOP PIN NO.
* ( ) IS 14SOP PINNO.
* TOGGLE FLIP FLOP USED ONLY IN UC3844, UC3845
|
|
UC3842/UC3843/UC3844/UC3845
UC3842/44 UC3843/45
Figure 2. Under Voltage Lockout
During Under-Voltage Lock-Out, the output driver is biased to a high impedance state. Pin 6 should be shunted to ground with
a bleeder resistor to prevent activating the power switch with output leakage current.
Figure 3. Error Amp Configuration
Figure 4. Current Sense Circuit
Peak current (IS) is determined by the formula:
IS(MAX)=
1----.--0---V---
RS
A small RC filter may be required to suppress switch transients.
5
Preview 5 Page |
Part DetailsOn this page, you can learn information such as the schematic, equivalent, pinout, replacement, circuit, and manual for UC3844 electronic component. |
Information | Total 11 Pages | |
Link URL | [ Copy URL to Clipboard ] | |
Download | [ UC3844.PDF Datasheet ] |
Share Link :
Electronic Components Distributor
An electronic components distributor is a company that sources, stocks, and sells electronic components to manufacturers, engineers, and hobbyists. |
SparkFun Electronics | Allied Electronics | DigiKey Electronics | Arrow Electronics |
Mouser Electronics | Adafruit | Newark | Chip One Stop |
Featured Datasheets
Part Number | Description | MFRS |
UC3840 | The function is PWM CONTROLLER. STMicroelectronics | |
UC3841 | The function is Programmable Off-Line PWM Controller. Texas Instruments | |
UC3842 | The function is Current Mode PWM Controller (Rev. C). Texas Instruments | |
Semiconductors commonly used in industry:
1N4148 |  
BAW56 |
1N5400 |
NE555 | | ||
Quick jump to:
UC38
1N4
2N2
2SA
2SC
74H
BC
HCF
IRF
KA |