- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄384534 > ISL97801ARZ-TK (INTERSIL CORP) High Power LED Driver PDF資料下載
參數(shù)資料
| 型號： | ISL97801ARZ-TK |
| 廠商： | INTERSIL CORP |
| 元件分類： | 顯示驅(qū)動器 |
| 英文描述： | High Power LED Driver |
| 中文描述： | LED DISPLAY DRIVER, PQCC20 |
| 封裝： | 4 X 4 MM, ROHS COMPLIANT, PLASTIC, QFN-20 |
| 文件頁數(shù)： | 12/19頁 |
| 文件大?。?/td> | 707K |
| 代理商： | ISL97801ARZ-TK |
12
FN6428.1
April 2, 2007
further improve the linearity of PWM dimming, an internal
timer delays system shutdown via EN/PWM for 50ms.
Bias Current Dimming
Current in the LED load is determined by the value of the
feedback resistor and the target feedback regulation voltage:
With MODE tied to VDC, voltage across the feedback
resistor is set by V
LEVEL
:
The value of V
FB
should be limited to between 50mV and
450mV for linear operation. For minimum light output, V
FB
may be set below 50mV. With MODE tied to GND, voltage
across the feedback resistor is set at ~400mV via an internal
reference. In either operating mode, if LED temperature
control is enabled the value of VFB will be reduced when
maximum LED temperature is exceeded.
Input Overvoltage
For automotive applications, an external high voltage NFET
driven by the FAULT pin disconnects the device from the
input supply in response to voltage spikes on the input
supply. During start-up an internal charge pump drives the
FAULT pin above the input voltage, ensuring the NFET is
fully enhanced and powering up the device. In normal
operation the switching node of the boost regulator or the
floating supply of the buck regulator is used to pump FAULT
above VIN. On detection of an overvoltage, the FAULT pin is
discharged to GND. The gate to source voltage of the
NDMOS is internally limited to ±15V to prevent voltage
stress.
Fault Protection
The external NFET is also used as a fault protection switch,
disconnecting the input supply if a fault occurs for more than
50ms. The system monitors feedback voltage regulation,
output overvoltage and input overvoltage. For applications
not requiring input voltage or fault protection, connect VBAT
and VIN directly together. All faults except input supply
overvoltage latch the ISL97801 into an off state that can be
cleared by either power cycling the input supply or the
EN/PWM pin. Connecting the TMAX pin to VDC disables the
fault latch function (LED over temperature control is also
disabled).
Output Overvoltage Protection (OVP)
If the FB pin is shorted to ground or an LED fails open
circuit, output voltage in BOOST mode can increase to
potentially damaging voltages. An optional overvoltage
protection circuit can be enabled by connection of the OVP
pin to the output voltage. The device will stop switching if the
output voltage exceeds OVPH and re-start when the output
voltage falls below OVPL. During sustained OVP fault
conditions, V
OUT
will saw-tooth between the upper and
lower threshold voltages at a frequency determined by the
magnitude of current available to discharge the output
capacitor and the value of output capacitor used.
The OVP threshold can be set to a lower value by using an
external zener diode and resistor, as shown in Figure 33. R1
should be adjusted to minimize offset in the FB voltage due
to FB pin input current. A value of 100
Ω
is recommended.
FIGURE 31. OPERATION WITH ENL CONTROLLED FET
FIGURE 32. OPERATION WITH NO ENL CONTROLLED FET
I
LED
V
SENSE
-----------------------
=
(EQ. 1)
V
FB
V
---------------------
=
(EQ. 2)
ISL97801
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| ISL9R1560P2 | 8A, 600V Stealth Diode(8A，600V Stealth二極管) |
| ISL9R860P2 | 8A, 600V Stealth Diode(8A，600V Stealth二極管) |
| ISO808 | Isolated 12-Bit Sampling Analog-To-Digital Converter(隔離的12位采樣A\D轉(zhuǎn)換器) |
| ISP321-1 | HIGH DENSITY MOUNTING PHOTOTRANSISTOR OPTICALLY COUPLED ISOLATORS |
| ISP321-1-88XSM | HIGH DENSITY MOUNTING PHOTOTRANSISTOR OPTICALLY COUPLED ISOLATORS |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| ISL97801BOOSTEVALZ | 功能描述:EVAL BOARD FOR ISL97801 RoHS:是 類別:編程器，開發(fā)系統(tǒng) >> 評估板 - LED 驅(qū)動器 系列:* 標準包裝:1 系列:PowerWise® 電流 - 輸出 / 通道:20mA 輸出及類型:1，非隔離 輸出電壓:17V 特點:可調(diào)光 輸入電壓:2.7 ~ 5.5 V 已供物品:板 已用 IC / 零件:LM3508 相關(guān)產(chǎn)品:LM3508TLX-ND - IC LED DRVR WHT BCKLGT 9USMDLM3508TLDKR-ND - IC LED DRVR WHT BCKLGT 9MICROSMDLM3508TLCT-ND - IC LED DRVR WHT BCKLGT 9MICROSMDLM3508TLTR-ND - IC LED DRVR WHT BCKLGT 9MICROSMD |
| ISL97900CRZ | 功能描述:LED照明驅(qū)動器 High Current RGB Driver/Controller, 28L 4x5 QFN, Commercial RoHS:否 制造商:STMicroelectronics 輸入電壓:11.5 V to 23 V 工作頻率: 最大電源電流:1.7 mA 輸出電流: 最大工作溫度: 安裝風格:SMD/SMT 封裝 / 箱體:SO-16N |
| ISL97900CRZ-T | 功能描述:LED照明驅(qū)動器 High Current RGB Driver/Controller, 28L 4x5 QFN, Commercial RoHS:否 制造商:STMicroelectronics 輸入電壓:11.5 V to 23 V 工作頻率: 最大電源電流:1.7 mA 輸出電流: 最大工作溫度: 安裝風格:SMD/SMT 封裝 / 箱體:SO-16N |
| ISL97900CRZ-T7A | 功能描述:LED照明驅(qū)動器 High Current RGB Driver/Controller, 28L 4x5 QFN,Commercial T RoHS:否 制造商:STMicroelectronics 輸入電壓:11.5 V to 23 V 工作頻率: 最大電源電流:1.7 mA 輸出電流: 最大工作溫度: 安裝風格:SMD/SMT 封裝 / 箱體:SO-16N |
| ISL97900CRZ-TK | 功能描述:LED照明驅(qū)動器 High Current RGB Driver/Controller, 28L 4x5 QFN, Commercial RoHS:否 制造商:STMicroelectronics 輸入電壓:11.5 V to 23 V 工作頻率: 最大電源電流:1.7 mA 輸出電流: 最大工作溫度: 安裝風格:SMD/SMT 封裝 / 箱體:SO-16N |
發(fā)布緊急采購，3分鐘左右您將得到回復。