- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄357718 > CS52843ED8 (ON SEMICONDUCTOR) 1 A SWITCHING CONTROLLER, PDSO8 PDF資料下載
參數(shù)資料
| 型號(hào)： | CS52843ED8 |
| 廠商： | ON SEMICONDUCTOR |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | 1 A SWITCHING CONTROLLER, PDSO8 |
| 封裝： | SOP-8 |
| 文件頁數(shù)： | 6/9頁 |
| 文件大?。?/td> | 240K |
| 代理商： | CS52843ED8 |
CS52843
http://onsemi.com
6
Figure 5. Startup Voltage for the CS52843
V
ON
= 8.4 V
V
OFF
= 7.6 V
ON/OFF Command to reset of IC
I
CC
V
CC
V
ON
V
OFF
V
CC
< 15 mA
< 500
μ
A
Undervoltage Lockout
During Undervoltage Lockout (Figure 5), the output
driver is biased to sink minor amounts of current. The output
should be shunted to ground with a resistor to prevent
activating the power switch with extraneous leakage
currents.
PWM Waveform
To generate the PWM waveform, the control voltage from
the error amplifier is compared to a current sense signal
which represents the peak output inductor current (Figure
6). An increase in V
CC
causes the inductor current slope to
increase, thus reducing the duty cycle. This is an inherent
feed
forward characteristic of current mode control, since
the control voltage does not have to change during changes
of input supply voltage.
When the power supply sees a sudden large output current
increase, the control voltage will increase allowing the duty
cycle to momentarily increase. Since the duty cycle tends to
exceed the maximum allowed to prevent transformer
saturation in some power supplies, the internal oscillator
waveform provides the maximum duty cycle clamp as
programmed by the selection of oscillator timing
components.
Figure 6. Timing Diagram
V
OSC
OSC
RESET
Toggle
F/F Output
EA Output
Switch
Current
V
CC
I
O
V
O
Setting the Oscillator
The times t
c
and t
d
can be determined as follows:
RTCTlnVREF
tc
VLOWER
VUPPER
td
RTCTln
VREF
VREF
IdRTVLOWER
IdRT
VUPPER
Substituting in typical values for the parameters in the
above formulas:
VREF
5.0 V,VUPPER
2.7 V,
VLOWER
1.0 V,Id
8.3 mA
then
tc
0.5534RTCT
td
RTCTln4.0
0.0083RT
0.0083RT
For better accuracy R
T
should be
≥
10 k
Ω
.
Grounding
High peak currents associated with capacitive loads
necessitate careful grounding techniques. Timing and
bypass capacitors should be connected close to GND in a
single point ground.
The transistor and 5.0 k
Ω
potentiometer are used to
sample the oscillator waveform and apply an adjustable
ramp to Sense.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| CS8128YN8 | 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDIP8 |
| CSDA1AC | SPECIALTY ANALOG CIRCUIT, XSS |
| CSHDD16-100ATR13 | 16 A, 100 V, SILICON, RECTIFIER DIODE |
| CSM6530 | 2 CHANNEL LOGIC OUTPUT OPTOCOUPLER, 0.4 Mbps |
| CSN043D-6R8M | GENERAL PURPOSE INDUCTOR |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| CS52843EDR14 | 制造商:Rochester Electronics LLC 功能描述:- Bulk 制造商:ON Semiconductor 功能描述: |
| CS52843EDR8 | 制造商:ONSEMI 制造商全稱:ON Semiconductor 功能描述:Current Mode PWM Control Circuit |
| CS52845 | 制造商:CHERRY 制造商全稱:CHERRY 功能描述:Current Mode PWM Control Circuit with 50% Max Duty Cycle |
| CS52845/D | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Current Mode PWM Control Circuit with 50% Max Duty Cycle |
| CS-52845D14 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Current-Mode SMPS Controller |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。