參數(shù)資料
型號(hào)： 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(yè)數(shù)： 14/26頁(yè)
文件大?。?/td> 296K
代理商： L4992
Pulse-skipping operation is enabled by default in order to maximize efficiency also in low load current
range. The transition between PWM and pulse-skipping occurs approximately below 1A, however there
is a region in which the two operation modes coexist rather than a definite boundary. That can be seen
on the scope as an irregularity of the waveforms but does not have much influence both on output ripple
and efficiency.
Those who do not appreciate asynchronous operation of the pulse-skipping mode can disable it for both
regulators, by setting switch 2 on 1. That maintains PWM operation up to very low output currents where,
however, the regulation becomes incompatible with the switching frequency. This means that the mini-
mum ON-time of the high-side MOSFET is too long for the thruput energy level at the operating fre-
quency. Thus the control system begins skipping conduction cycles to avoid the output voltage drifting
upwards.
Table 1 shows the complete L4992 EVAL KIT parts list. Critical components characteristics are given in
detail.
DEMO BOARD EVALUATION
The following diagrams and tables show the typical performance of the demonstration board in terms of
efficiency, line regulation and load regulation. The 12V linear regulator and REG5 are also characterized.
Table 2: PWM Regulators: Optimum Efficiency
Parameter
Test Condition
Value
Unit
+3.3V Maximum Efficiency
RUN3 = RUN5 = HIGH, NOSKIP = LOW
Vin = 6V, Iout = 0.5 A, fSW = 200 kHz
Vin = 6V, Iout = 1A, fSW = 300 kHz
95.2
94.6
%
+5.1V Maximum Efficiency
RUN3 = LOW, NOSKIP = LOW
Vin = 6V, Iout = 1A, fSW = 200 kHz
Vin = 6V, Iout = 1A, fSW = 300 kHz
96.4
95.8
%
DESIGN PROCEDURE (continued)
Table 3: PWM regulators: Line and Load Regulation.
Parameter
Test Condition
Value
Unit
+3.3V Line Regulation
RUN5 = LOW, NOSKIP = LOW, 6 < Vin < 20V
Iout = 0.1 A, fSW = 200 kHz
Iout =1A, fSW = 200 kHz
2
15
mV
+5.1V Line Regulation
RUN3 = LOW, NOSKIP = LOW, 6 < Vin < 20V
Iout = 0.1A, fSW = 200 kHz
Iout = 1A, fSW = 200 kHz
3
20
mV
+3.3V Load Regulation
RUN5 = LOW, NOSKIP = LOW, 5 mA < Iout < 3A
Vin = 6 V, fSW = 200 kHz
Vin = 15V, fSW = 200 kHz
85
70
mV
+5.1V Load Regulation
RUN3 = LOW, NOSKIP = LOW, 5 mA < Iout < 3A
Vin = 6 V, fSW = 200 kHz
Vin = 15V, fSW = 200 kHz
90
75
mV
L4992
21/26
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(dòng)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(dòng)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(dòng)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(dòng)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(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

*
*
*