- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄97995 > L4992 (STMICROELECTRONICS) SWITCHING CONTROLLER, 300 kHz SWITCHING FREQ-MAX, PQFP32 PDF資料下載
參數(shù)資料
| 型號： | L4992 |
| 廠商： | STMICROELECTRONICS |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | SWITCHING CONTROLLER, 300 kHz SWITCHING FREQ-MAX, PQFP32 |
| 封裝： | TQFP-32 |
| 文件頁數(shù)： | 2/26頁 |
| 文件大?。?/td> | 296K |
| 代理商： | L4992 |
第1頁當(dāng)前第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁
An auxiliary winding could be used also on the choke of the +5.1V section, either to power the +12V lin-
ear regulator or to derive a further supplemental output, however the 3.3 V section has been provided
with some features aimed at ensuring a proper operation under all circumstances.
For a correct operation of the regulator, the voltage at pin V13IN must not be too low. The flyback con-
nection of the two windings ensures a well regulated voltage, provided there is good magnetic coupling.
The coupled inductors configuration, however, is not able to sustain the auxiliary voltage if the main out-
put is lightly loaded: the secondary voltage drops and the system goes out of regulation.
To overcome this problem, when the V13IN voltage falls below a certain threshold (13.7 V +/- 5%) be-
cause of too light a load on the 3.3V section, the relevant synchronous rectifier is turned on for 1.5
s
max. during the interval in which the inductor current is zero ("one-shot" feature, see fig. 6). In this way,
the inductor current reverses and draws from the output capacitor energy which is forward transferred to
the auxiliary output.
In case the 3.3V section is working at full load and the linear regulator is lightly loaded, the voltage at pin
V13IN can exceed the expected value. In fact, Ds and Cs act as a peak-holding circuit and V13IN is in-
fluenced by the voltage spikes at switching transients. An internal clamp limits the voltage but, in case of
intervention, the chip power dissipation will rise.
When the 3.3V regulator is disabled, the linear regulator is disabled as well and is placed in a low-power
mode to reduce device consumption.
DETAILED FUNCTIONAL DESCRIPTION (continued)
1
n
DS
CS
to V13IN
3.3V
D97IN575
Figure 5: 12V regulator supply with auxiliary winding.
t
H3GATE
L3GATE
IL
D97IN576A
1.5
s
t
V13IN
13.7V
Figure 6: "One shot" feature to sustain V13IN voltage.
L4992
10/26
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| L5953 | 1.2 A SWITCHING REGULATOR, 425 kHz SWITCHING FREQ-MAX, PDSO36 |
| L5962 | SWITCHING REGULATOR, PDSO36 |
| L5973DD | 3.5 A SWITCHING REGULATOR, 280 kHz SWITCHING FREQ-MAX, PDSO8 |
| L5988D | 5.6 A SWITCHING REGULATOR, 1000 kHz SWITCHING FREQ-MAX, PDSO16 |
| L5994A | 1 A DUAL SWITCHING CONTROLLER, 345 kHz SWITCHING FREQ-MAX, PQFP32 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| L4993 | 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:Low drop voltage regulator |
| L4993D | 功能描述:低壓差穩(wěn)壓器 - LDO Low drop voltage regulator RoHS:否 制造商:Texas Instruments 最大輸入電壓:36 V 輸出電壓:1.4 V to 20.5 V 回動電壓（最大值）:307 mV 輸出電流:1 A 負(fù)載調(diào)節(jié):0.3 % 輸出端數(shù)量: 輸出類型:Fixed 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-20 |
| L4993DTR | 功能描述:低壓差穩(wěn)壓器 - LDO Low drop voltage regulator RoHS:否 制造商:Texas Instruments 最大輸入電壓:36 V 輸出電壓:1.4 V to 20.5 V 回動電壓（最大值）:307 mV 輸出電流:1 A 負(fù)載調(diào)節(jié):0.3 % 輸出端數(shù)量: 輸出類型:Fixed 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-20 |
| L4993MD | 功能描述:低壓差穩(wěn)壓器 - LDO Low drop voltage regulator RoHS:否 制造商:Texas Instruments 最大輸入電壓:36 V 輸出電壓:1.4 V to 20.5 V 回動電壓（最大值）:307 mV 輸出電流:1 A 負(fù)載調(diào)節(jié):0.3 % 輸出端數(shù)量: 輸出類型:Fixed 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-20 |
| L4993MDTR | 功能描述:低壓差穩(wěn)壓器 - LDO 5V 150mA LW DROP VLT REGULATOR RoHS:否 制造商:Texas Instruments 最大輸入電壓:36 V 輸出電壓:1.4 V to 20.5 V 回動電壓（最大值）:307 mV 輸出電流:1 A 負(fù)載調(diào)節(jié):0.3 % 輸出端數(shù)量: 輸出類型:Fixed 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-20 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。