- 您现在的位置：买卖IC网 > PDF目录20798 > ISL97634IRT14Z-TK (Intersil)IC LED DRIVR WHITE BCKLGT 8-TDFN PDF资料下载
参数资料
| 型号： | ISL97634IRT14Z-TK |
| 厂商： | Intersil |
| 文件页数： | 7/12页 |
| 文件大小： | 0K |
| 描述： | IC LED DRIVR WHITE BCKLGT 8-TDFN |
| 标准包装： | 1,000 |
| 拓扑： | PWM，升压（升压） |
| 输出数： | 1 |
| 内部驱动器： | 是 |
| 类型 - 主要： | 车载，背光 |
| 类型 - 次要： | 白色 LED |
| 频率： | 1.3MHz ~ 1.6MHz |
| 电源电压： | 2.4 V ~ 5.5 V |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 8-WFDFN 裸露焊盘 |
| 供应商设备封装： | 8-TDFN（2x3） |
| 包装： | 带卷 (TR) |
| 工作温度： | -40°C ~ 85°C |
ISL97634
however, the dimming linearity is compromised at low duty
cycles as their durations are too short for the ISL97634’s control
loop to respond properly. This non-ideality behavior does not
cause any functional problem. The PWM dimming linear
responses in Figure 6 are expanded in Figure 11. At 1kHz PWM
dimming, the duty cycle can virtually vary from below 1% to DC.
On the other hand, at 20kHz PWM dimming, the linearity range is
from 5% to DC only.
.
V OUT
LX
10
7 LEDs
PWM/EN
9
8
7
V IN = 4V
RSET = 4 Ω
L = 10μH
1kHz
ILED
V IN = 4V
R1 = 4 Ω
L1 = 22μH
6
5
4
FIGURE 13. PWM DIMMING AT 1kHz WITHOUT USING FBSW
The FBSW should be used for PWM dimming as illustrated in the
3
2
1
32kHz
20kHz
“Typical Application Circuit” on page 1. During the PWM off time,
the FBSW is opened. The LEDs are floating and therefore the
output capacitor has no path to discharge. The LED current
responds accurately with the PWM signal (see Figure 14). The
0
0 2 4 6 8 10
DUTY CYCLE (%)
FIGURE 11. DIMMING LINEARITY vs DUTY CYCLES ZOOM IN
The low level non-linearity effects at high frequency PWM
12
output switches very quickly to the target current with minimal
settling ringing and without being modulated by the PWM signal,
and therefore minimizes any system disturbance.
dimming is also reflected in the efficiency measurements in
V OUT
Figure 12.
90
LX
85
80
75
70
65
PWM/EN
V IN = 4V
R1 = 4 Ω
L1 = 22μH
60
55
3 LEDs
V IN = 4V
RSET = 4 Ω
L = 22μH
ILED
50
0
5
10
15
20
25
30
FIGURE 14. PWM DIMMING AT 1kHz USING FBSW
ILED (mA)
FIGURE 12. EFFICIENCY vs PWM DIMMING FREQUENCIES
Feedback Disconnect Switch
The ISL97634 functions properly without using the FBSW.
However, the output capacitor will discharge during the PWM off
time resulting in poor dimming linearity at low duty cycles. The
output discharge effect can be seen in Figure 13. Moreover, the
output is modulated by the PWM signal that may create
interference to other systems.
7
Overvoltage Protection
The ISL97634 comes with overvoltage protection. The OVP trip
points are at 14V, 18V and 26V for ISL97634IRT14Z,
ISL97634IRT18Z and ISL97634IRT26Z respectively. The
maximum LED current and OVP threshold are shown in Table 1.
When the device reaches the OVP, the LX stops switching,
disabling the boost circuit until V OUT falls about 7% below the OVP
threshold. At this point, LX will be allowed to switch again. The OVP
event will not cause the device to shutdown.
An output capacitor that is only rated for the required voltage
range can therefore be used, which will optimize the component
costs in some cases.
FN6264.4
August 27, 2013
相关PDF资料 |
PDF描述 |
|---|---|
| ISL97634IRT14Z-T | IC LED DRIVR WHITE BCKLGT 8-TDFN |
| REC7.5-2405DRW/H3/A/M/CTRL | CONV DC/DC 7.5W 18-36VIN +/-05V |
| REC3-4809SRWZ/H2/C/M | CONV DC/DC 3W 18-72VIN 09VOUT |
| P51-750-S-E-MD-5V-000-000 | SENSOR 750PSIS 3/8 UNF 5V MINI |
| USR 2-0808 500 OHM D 0.01% 1PPM | RES 500 OHM .6W .01% FOIL RADIAL |
相关代理商/技术参数 |
参数描述 |
|---|---|
| ISL97634IRT18Z | 制造商:Intersil 功能描述:White LED Driver with PWM Dimming(4 LED) |
| ISL97634IRT18Z-T | 功能描述:IC LED DRIVR WHITE BCKLGT 8-TDFN RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- 恒定电流:- 恒定电压:- 拓扑:升压（升压），切换式电容器（充电泵） 输出数:1 内部驱动器:是 类型 - 主要:背光 类型 - 次要:白色 LED 频率:625kHz ~ 875kHz 电源电压:2.7 V ~ 5.3 V 输出电压:5V 安装类型:表面贴装 封装/外壳:10-TFSOP，10-MSOP（0.118"，3.00mm 宽） 供应商设备封装:10-µMAX 包装:带卷 (TR) 工作温度:-40°C ~ 85°C |
| ISL97634IRT18Z-TK | 功能描述:IC LED DRIVR WHITE BCKLGT 8-TDFN RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- 恒定电流:- 恒定电压:- 拓扑:升压（升压），切换式电容器（充电泵） 输出数:1 内部驱动器:是 类型 - 主要:背光 类型 - 次要:白色 LED 频率:625kHz ~ 875kHz 电源电压:2.7 V ~ 5.3 V 输出电压:5V 安装类型:表面贴装 封装/外壳:10-TFSOP，10-MSOP（0.118"，3.00mm 宽） 供应商设备封装:10-µMAX 包装:带卷 (TR) 工作温度:-40°C ~ 85°C |
| ISL97634IRT26Z-T | 功能描述:IC LED DRIVR WHITE BCKLGT 8-TDFN RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- 恒定电流:- 恒定电压:- 拓扑:升压（升压），切换式电容器（充电泵） 输出数:1 内部驱动器:是 类型 - 主要:背光 类型 - 次要:白色 LED 频率:625kHz ~ 875kHz 电源电压:2.7 V ~ 5.3 V 输出电压:5V 安装类型:表面贴装 封装/外壳:10-TFSOP，10-MSOP（0.118"，3.00mm 宽） 供应商设备封装:10-µMAX 包装:带卷 (TR) 工作温度:-40°C ~ 85°C |
| ISL97634IRT26Z-TK | 功能描述:IC LED DRIVR WHITE BCKLGT 8-TDFN RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- 恒定电流:- 恒定电压:- 拓扑:升压（升压），切换式电容器（充电泵） 输出数:1 内部驱动器:是 类型 - 主要:背光 类型 - 次要:白色 LED 频率:625kHz ~ 875kHz 电源电压:2.7 V ~ 5.3 V 输出电压:5V 安装类型:表面贴装 封装/外壳:10-TFSOP，10-MSOP（0.118"，3.00mm 宽） 供应商设备封装:10-µMAX 包装:带卷 (TR) 工作温度:-40°C ~ 85°C |
发布紧急采购，3分钟左右您将得到回复。