- 您现在的位置：买卖IC网 > PDF目录67322 > PWM5031-001-2S 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, CDSO24 PDF资料下载
参数资料
| 型号： | PWM5031-001-2S |
| 元件分类： | 稳压器 |
| 英文描述： | 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, CDSO24 |
| 封装： | 0.600 X 0.300 INCH, 0.130 INCH HEIGHT, HERMETIC SEALED, CERAMIC, SOP-24 |
| 文件页数： | 6/19页 |
| 文件大小： | 236K |
| 代理商： | PWM5031-001-2S |
14
SCD5031 Rev L 11/3/08
Aeroflex Plainview
TYPICAL APPLICATIONS
Like all current mode PWMs, the chip provides built in fault protection by limiting peak switch current on a cycle by
cycle basis. When an overload condition occurs, the sensed current reaches the current trip threshold earlier in the
switching cycle than it otherwise would and thus forces the PWM latch off until the start of the next cycle. The process
repeats until the overload condition is removed and the PWM can return to a normal duty cycle. The chip is capable of
operating in this mode indefinitely without sustaining damage.
There are two ways to set the current limit trip point. One is to simply tailor the sense resistor Rs:
Some users may find the power is dissipated in Rs to be unacceptably high. In this case, the user can fix Rs at a small
value and vary the current comparator threshold instead. Fortunately, the PWM chip provides a very convenient method
for doing so. Because the error amplifier output is internally clamped to the SOFT pin, the user need simply apply the
desired voltage level to the SOFT pin to arbitrarily lower the current comparator threshold.
Recalling that the EA output is level shifted and divided before being applied to the comparator input, the peak current
limit is chosen by applying a voltage VSOFT such that:
Clamping the EA output to the soft pin also makes implementing a softstart ciruit easy. Rsoft and Csoft are connected as
in Figure 9 to provide the SOFT pin an asymptotically rising voltage. Because of the internal clamp on the EA output,
the PWM duty cycle will increase only as fast as the chosen time constant will allow. In this way, excessive duty cycle
and surge currents into the output capacitors are avoided. A transistor may be optionally connected across the softstart
FIGURE 9 – Typical Forward Converter Application
Rset
Cset
CSOFT
0.1F
RSOFT
M2
C1
R1
Rs
T1
Isolation Barrier
3.3V, 0.5A
Opto-Isolator or
Pulse Transformer
Optional circuit
to force zero
duty cycle
M1
RSET
CSET
VEE DRVN
VFB
COMP
50%
ISENSE
Out A
Out B
VCC
DRVP
EN
SOFT
VREF
+5VDC
I
pk
1.0Vdc
R
s
-------------------
=
I
pk
V
soft
1.4
–
3
R
s
×
-------------------------
=
1.4V
V
soft
4.4V
≤≤
相关PDF资料 |
PDF描述 |
|---|---|
| PWM5031-S | 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, CDSO24 |
| PWM5032-DIE | 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, UUC |
| PWM5031-DIE | 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, UUC |
| PWM5031-001-1S | 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, CDSO24 |
| PWM5034-7 | 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, CDSO24 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| PWM5031-7 | 制造商:AEROFLEX 制造商全称:AEROFLEX 功能描述:RadHard High Speed PWM Controller |
| PWM5031-I | 制造商:AEROFLEX 制造商全称:AEROFLEX 功能描述:RadHard High Speed PWM Controller |
| PWM5031-S | 制造商:AEROFLEX 制造商全称:AEROFLEX 功能描述:RadHard High Speed PWM Controller |
| PWM505 | 制造商:未知厂家 制造商全称:未知厂家 功能描述:Analog IC |
| PWM-50-59 | 制造商:Brady Corporation 功能描述:REFILL PAGES - LEGEND: 50-59 |
发布紧急采购，3分钟左右您将得到回复。