參數(shù)資料
型號: LM3524DM
廠商: NATIONAL SEMICONDUCTOR CORP
元件分類: 穩(wěn)壓器
英文描述: Regulating Pulse Width Modulator
中文描述: 0.2 A SWITCHING CONTROLLER, 350 kHz SWITCHING FREQ-MAX, PDSO16
封裝: PLASTIC, SMT-16
文件頁數(shù): 17/22頁
文件大?。?/td> 1172K
代理商: LM3524DM
Typical Applications
(Continued)
THE STEP-UP SWITCHING REGULATOR
Figure 18
shows the basic circuit for a step-up switching
regulator. In this circuit Q1 is used as a switch to alternately
apply V
IN
across inductor L1. During the time, t
ON
, Q1 is ON
and energy is drawn from V
IN
and stored in L1; D1 is reverse
biased and I
o
is supplied from the charge stored in C
. When
Q1 opens, t
, voltage V1 will rise positively to the point
where D1 turns ON. The output current is now supplied
through L1, D1 to the load and any charge lost from C
o
during t
is replenished. Here also, as in the step-down
regulator, the current through L1 has a DC component plus
some
I
.
I
L
is again selected to be approximately 40% of
I
.
Figure 19
shows the inductor’s current in relation to Q1’s
ON and OFF times.
Since
I
L
+ =
I
L
, V
IN
t
ON
= V
o
t
OFF
V
IN
t
OFF
,
and neglecting V
SAT
and V
D1
The above equation shows the relationship between V
IN
, V
o
and duty cycle.
In calculating input current I
IN(DC)
, which equals the induc-
tor’s DC current, assume first 100% efficiency:
for
η
= 100%, P
OUT
= P
IN
00865023
FIGURE 18. Basic Step-Up Switching Regulator
00865024
FIGURE 19. Relation of Switch Timing to Inductor Current in Step-Up Regulator
L
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相關(guān)PDF資料
PDF描述
LM3524 Regulating Pulse Width Modulator
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相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LM3524DM/NOPB 功能描述:電壓模式 PWM 控制器 REGULATING PULSE WIDTH MODULATOR RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓?fù)浣Y(jié)構(gòu):Buck 輸出電壓:34 V 輸出電流: 開關(guān)頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel
LM3524DM/NOPB 制造商:Texas Instruments 功能描述:Pulse Width Modulation (PWM) Controller
LM3524DMX 功能描述:電壓模式 PWM 控制器 RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓?fù)浣Y(jié)構(gòu):Buck 輸出電壓:34 V 輸出電流: 開關(guān)頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel
LM3524DMX/NOPB 功能描述:電壓模式 PWM 控制器 RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓?fù)浣Y(jié)構(gòu):Buck 輸出電壓:34 V 輸出電流: 開關(guān)頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel
LM3524DN 功能描述:電壓模式 PWM 控制器 RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓?fù)浣Y(jié)構(gòu):Buck 輸出電壓:34 V 輸出電流: 開關(guān)頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel