參數(shù)資料
型號(hào)： L5994
廠商： STMICROELECTRONICS
元件分類： 穩(wěn)壓器
英文描述： 1 A DUAL SWITCHING CONTROLLER, 345 kHz SWITCHING FREQ-MAX, PQFP32
封裝： TQFP-32
文件頁(yè)數(shù)： 4/26頁(yè)
文件大?。?/td> 322K
代理商： L5994
Obsolete
Product(s)
- Obsolete
Product(s)
L5994 - L5994A
12/26
works in order to obtain a voltage on the VFBLIN pin of about 2.5V. In this way, the minimum regulated voltage
is of 2.5V, obtained connecting directly the VFBLIN pin to the output, while the maximum is of about the supply
voltage minus the bipolar PNP VceSAT.
For a correct operation of the regulator, the voltage at pin VDRLIN must not be too low. The flyback connection
of the two windings ensures a well regulated voltage, provided if there is good magnetic coupling. The coupled
inductors configuration, however, is not able to sustain the auxiliary voltage if the main output is lightly loaded:
the secondary voltage drops and the system goes out of regulation.
The additional winding may be implemented with L5994 if the relative section is loaded enough.
To overcome this problem, in L5994A, when the VDRLIN voltage falls below a certain threshold (13.7V ±5%)
because of too light a load on the section 2, 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.
Since that the linear driver is supplied from the VDRLIN pin, if the linear regulator is not necessary for the application,
leave floating this pin implies that the linear driver is not supplied and so no power is wasted (L5994 only).
The linear regulator is active, if at the least one of the two runx signal is asserted
Figure 5. "One Shot" pulse to substain VDRLIN voltage
+5V Linear Regulator and +2.5V Reference Voltage Generator
The 5V low drop-out regulator powers directly the MOSFET drivers and it is externally available through pin
PREG5. A low pass filter is connected between PREG5 pin and SREG5 pin from who all the internal circuitry is
powered. The introduction of this R-C network is useful to minimize noise effects.
The typical external use of this generator is to charge the bootstrap capacitors used to produce the gate-drive
voltage for the high-side MOSFET's of both PWM converters.
At start-up and when the 5V section is not operating, this regulator is powered by the chip input voltage. To re-
duce power consumption, the linear regulator is turned off and the PREG5 pin is internally connected to the 5V
PWM regulator output via V5SW pin, when the 5V PWM regulator is active and its output voltage is above the
switchover threshold, 4.5V. This happens when V5SW pin is connected to the section 1 output regulating 5V.
In any case, if V5SW is above 4.5V, the internal regulator is turned off and PREG5 is powered through this pin.
t
H1GATE
L1GATE
IL
1.5
s
t
V13IN
13.7V
相關(guān)PDF資料
PDF描述
L6206PD013TR STEPPER MOTOR CONTROLLER, 5.6 A, PDSO36
L6207PD013TR STEPPER MOTOR CONTROLLER, 5.6 A, PDSO36
L6219DSA STEPPER MOTOR CONTROLLER, 1 A, PDSO24
L6228PDTR STEPPER MOTOR CONTROLLER, 2.8 A, PDSO36
L6228DTR STEPPER MOTOR CONTROLLER, 2.8 A, PDSO24
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
L5994_02 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:ADJUSTABLE TRIPLE OUTPUT POWER SUPPLY CONTROLLER
L5994A 功能描述:監(jiān)控電路 ADJT TRIPLE OUTPUT POWER SUPPLY CNTLR RoHS:否 制造商:STMicroelectronics 監(jiān)測(cè)電壓數(shù): 監(jiān)測(cè)電壓: 欠電壓閾值: 過(guò)電壓閾值: 輸出類型:Active Low, Open Drain 人工復(fù)位:Resettable 監(jiān)視器:No Watchdog 電池備用開(kāi)關(guān):No Backup 上電復(fù)位延遲（典型值）:10 s 電源電壓-最大:5.5 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:UDFN-6 封裝:Reel
L5995 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Current-Mode SMPS Controller
L5996 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:5 BIT DYNAMIC DAC CONTROLLER FOR MOBILE CPU
L-59BL/1EGW 制造商:Kingbright Corporation 功能描述: 制造商:Kingbright Corporation 功能描述:LED 5MM RED/GREEN 40MCD/60MCD 制造商:Kingbright Corporation 功能描述:LED, 5MM, RED/GREEN, 40MCD/60MCD 制造商:Kingbright Corporation 功能描述:LED, 5MM, RED/GREEN, 40MCD/60MCD, LED Colour:Red, Green, Height:7.24mm, Width:7. 制造商:Kingbright Corporation 功能描述:Red/grn r/a cbi,5mm,L-59BL/1EGW
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫(xiě)一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*