- 您现在的位置：买卖IC网 > PDF目录19325 > UBA2071AT/N1,118 (NXP Semiconductors)IC DVR HALF BRIDGE 24-SOIC PDF资料下载
参数资料
| 型号： | UBA2071AT/N1,118 |
| 厂商： | NXP Semiconductors |
| 文件页数： | 15/35页 |
| 文件大小： | 0K |
| 描述： | IC DVR HALF BRIDGE 24-SOIC |
| 标准包装： | 1,000 |
| 类型： | CCFL/EEFL 控制器 |
| 频率： | 38 ~ 42kHz |
| 电流 - 电源： | 1.5mA |
| 电源电压： | 14V |
| 工作温度： | -25°C ~ 100°C |
| 封装/外壳： | 24-SOIC（0.295"，7.50mm 宽） |
| 供应商设备封装： | 24-SO |
| 包装： | 带卷 (TR) |
| 其它名称： | 935285776118 |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页当前第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页
NXP Semiconductors
UBA2071; UBA2071A
Half bridge control IC for CCFL backlighting
to CCFLs
Ich(CSWP)
Idch(CSWP)
IFB
OTA
PWMD
0
1
S2
DSR
R1
Vref(creg)
UBA2071
S1
Ich(CVFB)
to VCO
CIFB
C1
CVFB
C2
CSWP
C3
014aaa106
Fig 11. Lamp frequency control circuit
Under normal operating conditions, the voltage across capacitor C2, which is connected
to the CVFB pin, will follow the voltage on the CIFB pin. During the lamps-on period of the
PWM dimming, the voltage across C3, which is connected to the CSWP pin, will follow the
voltage on the CVFB pin and therefore also the voltage on the CIFB pin.
The voltage on the CSWP pin is connected to the VCO input of the HF oscillator and thus
controls the switching frequency. If the load is assumed to be inductive an increase in the
frequency will cause a decrease in the lamp current, while a decrease in the frequency will
cause an increase in the lamp current.
The advantage of having a separate current regulation loop timing capacitor pin CIFB next
to the voltage regulation loop timing capacitor CVFB is that time constants for both loops
can be set independently. The separate PWM dimming sweep timing capacitor pin CSWP
makes it possible to set the PWM dimming sweep speed independent of the current and
voltage regulation loops.
8.11 PWM dimming
Pulse Width Modulation (PWM) dimming is a method of reducing the average lamp light
output by switching the lamps on and off with a repetition rate or PWM frequency, f PWM ,
high enough not to be seen by the human eye (but much lower than the inverter frequency
f sw ). By varying the lamp-on to lamp-off, period ratio, called the duty cycle δ PWM , the light
output can be varied over a wide range.
The voltage at the CSWP pin determines the actual switching frequency, it inverses in
proportion to the switching frequency. During the lamps-on period of the PWM dimming it
follows the voltage at the CVFB pin (the current I ch(CSWP) is drained by the tracking circuit
between the CVFB pin and the CSWP pin).
Just prior to transitioning towards the lamps-off period of the PWM dimming the lamp
current control loop, see Figure 11 , is opened by opening switches S1. The voltage on the
CSWP pin is swept down, decaying the lamp current, leading in the PWM lamp-off
situation, after which the half bridge switch actions are stopped, resulting in true zero lamp
current. see Figure 9 . In the meantime the regulation level is preserved in C1 and C2. The
UBA2071_A_1
? NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 01 — 23 June 2008
15 of 35
相关PDF资料 |
PDF描述 |
|---|---|
| R24P205S/R8 | CONV DC/DC 2W 24VIN 05VOUT |
| EP2AGX45DF29I3N | IC ARRIA II GX FPGA 45K 780FBGA |
| ASM25DRMT-S288 | CONN EDGECARD 50POS .156 EXTEND |
| EPF10K100ARC240-1N | IC FLEX 10KA FPGA 100K 240-RQFP |
| RAC10-12DA-ST | CONV AC/DC 90-264VAC +/-12V .38A |
相关代理商/技术参数 |
参数描述 |
|---|---|
| UBA2071ATS | 制造商:PHILIPS 制造商全称:NXP Semiconductors 功能描述:Half bridge control IC for CCFL backlighting |
| UBA2071ATS/N1,118 | 功能描述:显示驱动器和控制器 CCFL DRVR 14V 24-Pin RoHS:否 制造商:Panasonic Electronic Components 工作电源电压:2.7 V to 5.5 V 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:QFN-44 封装:Reel |
| UBA2071T | 制造商:PHILIPS 制造商全称:NXP Semiconductors 功能描述:Half bridge control IC for CCFL backlighting |
| UBA2071T/N1,118 | 功能描述:显示驱动器和控制器 Half brdg control IC for CCFL bcklighting RoHS:否 制造商:Panasonic Electronic Components 工作电源电压:2.7 V to 5.5 V 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:QFN-44 封装:Reel |
| UBA2071TS | 制造商:PHILIPS 制造商全称:NXP Semiconductors 功能描述:Half bridge control IC for CCFL backlighting |
发布紧急采购，3分钟左右您将得到回复。