參數資料
型號: LM2585S-12
廠商: NATIONAL SEMICONDUCTOR CORP
元件分類: 穩(wěn)壓器
英文描述: SIMPLE SWITCHER 3A Flyback Regulator
中文描述: 7 A SWITCHING REGULATOR, 125 kHz SWITCHING FREQ-MAX, PSSO5
封裝: TO-263, 5 PIN
文件頁數: 17/25頁
文件大?。?/td> 627K
代理商: LM2585S-12
Step-Up (Boost) Regulator Operation
Figure 30 shows the LM2585 used as a step-up (boost)
regulator. This is a switching regulator that produces an out-
put voltage greater than the input supply voltage.
A brief explanation of how the LM2585 Boost Regulator
works is as follows (refer to Figure 30). When the NPN
switch turns on, the inductor current ramps up at the rate of
V
IN
/L, storing energy in the inductor. When the switch turns
off, the lower end of the inductor flies above V
, discharging
its current through diode (D) into the output capacitor (C
)
at a rate of (V
V
)/L. Thus, energy stored in the induc-
tor during the switch on time is transferred to the output dur-
ing the switch off time. The output voltage is controlled by
adjusting the peak switch current, as described in the flyback
regulator section.
DS012515-48
By adding a small number of external components (as shown in Figure 30), the LM2585 can be used to produce a regulated output voltage that is greater than
FIGURE 30. 12V Boost Regulator
DS012515-49
A: Switch Voltage, 10 V/div
B: Switch Current, 2 A/div
C: Inductor Current, 2 A/div
D: Output Ripple Voltage,
100 mV/div, AC-Coupled
Horizontal: 2 μs/div
FIGURE 31. Switching Waveforms
DS012515-50
FIGURE 32. V
OUT
Response to Load Current Step
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相關代理商/技術參數
參數描述
LM2585S-12/NOPB 功能描述:直流/直流開關轉換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT
LM2585S-3.3 功能描述:直流/直流開關轉換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT
LM2585S-3.3/NOPB 功能描述:直流/直流開關轉換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT
LM2585S-5.0 功能描述:直流/直流開關轉換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT
LM2585S-5.0/NOPB 功能描述:直流/直流開關轉換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT