參數(shù)資料
型號(hào)： LM3402HVMR
廠商： NATIONAL SEMICONDUCTOR CORP
元件分類(lèi)： 穩(wěn)壓器
英文描述： 0.5A Constant Current Buck Regulator for Driving High Power LEDs
中文描述： 0.94 A SWITCHING REGULATOR, PDSO8
封裝： PLASTIC, TSOP-8
文件頁(yè)數(shù)： 11/24頁(yè)
文件大?。?/td> 431K
代理商： LM3402HVMR
20192105
FIGURE 1. Comparator and One-Shot
The LM3402/02HV regulators should be operated in contin-
uous conduction mode (CCM), where inductor current stays
positive throughout the switching cycle. During steady-state
operationin the CCM, the converter maintains a constant
switching frequency, which can be selected using the follow-
ing equation:
V
F
= forward voltage of each LED, n = number of LEDs in
series
AVERAGE LED CURRENT ACCURACY
The COT architecture regulates the valley of
Δ
V
, the AC
portion of V
. To determine the average LED current (which
is also the average inductor current) the valley inductor cur-
rent is calculated using the following expression:
In this equation t
represents the propagation delay of the
CS comparator, and is approximately 220 ns. The average
inductor/LED current is equal to I
L-MIN
plus one-half of the in-
ductor current ripple,
Δ
i
L
:
I
F
= I
L
= I
L-MIN
+ Δ
i
L
/ 2
Detailed information for the calculation of
Δ
i
L
is given in the
Design Considerations section.
MAXIMUM OUTPUT VOLTAGE
The 300 ns minimum off-time limits on the maximum duty cy-
cle of the converter, D
, and in turn ,the maximum output
voltage V
O(MAX)
is determined by the following equations:
The maximum number of LEDs, n
, that can be placed in
a single series string is governed by V
and the maxi-
mum forward voltage of the LEDs used, V
F(MAX)
, using the
expression:
At low switching frequency the maximum duty cycle and out-
put voltage are higher, allowing the LM3402/02HV to regulate
output voltages that are nearly equal to input voltage. The
following equation relates switching frequency to maximum
output voltage.
MINIMUM OUTPUT VOLTAGE
The minimum recommended on-time for the LM3402/02HV is
300 ns. This lower limit for t
ON
determines the minimum duty
cycle and output voltage that can be regulated based on input
voltage and switching frequency. The relationship is deter-
mined by the following equation:
11
www.national.com
L
相關(guān)PDF資料
PDF描述
LM3402HVMRX 0.5A Constant Current Buck Regulator for Driving High Power LEDs
LM3402MR 0.5A Constant Current Buck Regulator for Driving High Power LEDs
LM3402MRX 0.5A Constant Current Buck Regulator for Driving High Power LEDs
LM3405A 1.6MHz, 1A Constant Current Buck LED Driver with Internal Compensation in Tiny SOT23 Package
LM3405AXMK 1.6MHz, 1A Constant Current Buck LED Driver with Internal Compensation in Tiny SOT23 Package
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LM3402HVMR/NOPB 功能描述:開(kāi)關(guān)變換器、穩(wěn)壓器與控制器 RoHS:否 制造商:Texas Instruments 輸出電壓:1.2 V to 10 V 輸出電流:300 mA 輸出功率: 輸入電壓:3 V to 17 V 開(kāi)關(guān)頻率:1 MHz 工作溫度范圍: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:WSON-8 封裝:Reel
LM3402HVMRX 制造商:NSC 制造商全稱(chēng):National Semiconductor 功能描述:0.5A Constant Current Buck Regulator for Driving High Power LEDs
LM3402HVMRX/NOPB 功能描述:開(kāi)關(guān)變換器、穩(wěn)壓器與控制器 RoHS:否 制造商:Texas Instruments 輸出電壓:1.2 V to 10 V 輸出電流:300 mA 輸出功率: 輸入電壓:3 V to 17 V 開(kāi)關(guān)頻率:1 MHz 工作溫度范圍: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:WSON-8 封裝:Reel
LM3402MM 功能描述:開(kāi)關(guān)變換器、穩(wěn)壓器與控制器 RoHS:否 制造商:Texas Instruments 輸出電壓:1.2 V to 10 V 輸出電流:300 mA 輸出功率: 輸入電壓:3 V to 17 V 開(kāi)關(guān)頻率:1 MHz 工作溫度范圍: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:WSON-8 封裝:Reel
LM3402MM/HALF 制造商:Texas Instruments 功能描述:DRIVER LED 0.5A POWERWISE MSOP8
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

*
*
*