- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄67322 > PWM5032-7 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, CDSO24 PDF資料下載
參數(shù)資料
| 型號： | PWM5032-7 |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, CDSO24 |
| 封裝： | 0.600 X 0.300 INCH, 0.130 INCH HEIGHT, HERMETIC SEALED, CERAMIC PACKAGE-24 |
| 文件頁數(shù)： | 7/19頁 |
| 文件大?。?/td> | 224K |
| 代理商： | PWM5032-7 |
15
SCD5031 Rev P 4/22/10
Aeroflex Plainview
capacitor to force zero duty cycle on command. This is a particularly convenient method for implementing an externally
controlled turn-on delay.
The discussion so far assumes the user operates the chip in the current mode: switch current is sensed and compared to
the error between the output voltage and a precision reference. Alternatively, the user may wish to implement voltage
mode control in which the control loop is dependent only on the output voltage. The PWM chip readily supports this
configuration with the following modification:
FIGURE 10 – Circuit for implementing voltage mode control.
A portion of the oscillator’s sawtooth waveform is coupled to the ISENSE pin and becomes the input to the comparator
stage. The operation is now identical to the current mode application: when the sawtooth voltage exceeds the amplified
difference between the output and a voltage reference, the comparator fires and latches off the output until the start of the
next cycle.
SELECTED APPLICATION EXAMPLES
The flexibility and performance of the chip makes it suitable for an enormous range of power converter applications –
step-up, step-down, DC-DC, AC-DC, isolated/non-isolated, and many more. This section will cover two of the more
popular power converter applications for which this chip is particularly well suited although many more can be
envisioned.
5V INPUT, 3.3V ISOLATED OUTPUT (SINGLE ENDED FORWARD CONVERTER)
The isolated step down DC/DC converter is a staple of many satellite and aerospace systems. A common bus distributes
raw primary power to various system loads which must then convert the primary to one or more low voltage secondary
outputs. These outputs are filtered, regulated, and ground isolated from the primary side to keep EMI and undesired
subsystem interaction at a minimum. Figure 9 is one example of a circuit that very efficiently performs this conversion.
The values here were chosen to work for a 5V input and 3.3V output but the circuit topology is general enough to
support an infinite variety of applications. For example, output voltages can be adjusted by changing values of just a few
components. A wider input voltage range can be supported by varying the transformer’s turns ratios and by proper
selection of M1. Thus, a very wide range of power converter applications can be satisfied by simple variations of the
circuit.
At the start of each switching cycle, the PWM output goes high and turns on M1. Energy is coupled across T1’s turns
ratios to the secondary side where it is caught, rectified, and filtered to produce a clean DC voltage. A sampling network
on the output side feeds back a portion of the output across the isolation barrier into the error amplifier negative input.
This feedback can be accomplished in a number of different ways: pulse transformers, optocouplers, or capacitive
coupling are a few methods. The compensation network may need modification depending on the feedback method
chosen. The additional winding and rectifier on T1 are used to reset the transformer core after the PWM latches off M1
to prevent staircase saturation of the core.
Note the chip is powered directly from the main power bus (via a zener and current limit resistor) without the need for
additional bootstrap transformer windings. This is one of the main advantages this PWM chip provides over other
products. This scheme could not be implemented with other chips which draw significantly more current. On the other
hand, supplying bias to our PWM chip is about as simple as it gets.
Out
Isense
Vref
2N2222
Cset
M1
Switch
Current
相關PDF資料 |
PDF描述 |
|---|---|
| PWM5034-S | 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, CDFP24 |
| PWM5034-7 | 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, CDFP24 |
| PWM5031-7 | 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, CDSO24 |
| 5962-0625102KYC | 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, CDSO24 |
| 5962-0625101KXC | 1 A SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, CDSO24 |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| PWM505 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog IC |
| PWM-50-59 | 制造商:Brady Corporation 功能描述:REFILL PAGES - LEGEND: 50-59 |
| PWM510 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog IC |
| PWM-6 | 制造商:Brady Corporation 功能描述: |
| PWM-60-12 | 功能描述:O/P +12V5A 制造商:mean well usa inc. 系列:PWM-60 零件狀態(tài):在售 類型:恒定電壓 拓撲:AC DC 轉換器 輸出數(shù):1 電壓 - 輸入（最小值）:90VAC 電壓 - 輸入（最大值）:305VAC 電壓 - 輸出:12V 電流 - 輸出（最大值）:5A 功率（W）:60W 電壓 - 隔離:3750V 調光:模擬，PWM 特性:OCP，OTP，OVP，SCP 等級:IP67 工作溫度:-40°C ~ 85°C 效率:86% 端子類型:導線引線 大小/尺寸:5.91" 長 x 2.09" 寬 x 1.38" 高（150.0mm x 53.0mm x 35.0mm） 安裝類型:底座安裝 認可:CB，CCC，CE，cURus，ENEC 標準包裝:1 |
發(fā)布緊急采購，3分鐘左右您將得到回復。