参数资料
| 型号： | ISL97522IRZ-TK |
| 厂商： | Intersil |
| 文件页数： | 15/20页 |
| 文件大小： | 0K |
| 描述： | IC SUPPLY CTRL 4CH TFT-LCD 38QFN |
| 标准包装： | 1,000 |
| 应用： | LCD 电视机/监控器 |
| 电流 - 电源： | 3mA |
| 电源电压： | 4.5 V ~ 13.2 V |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 38-VFQFN 裸露焊盘 |
| 供应商设备封装： | 38-QFN（5x7） |
| 包装： | 带卷 (TR) |
ISL97522
The following equation gives the boundary between
CHARGE PUMP
V IN OUTPUT
OR A VDD
3k Ω
discontinuous and continuous boost operation. For continuous
operation (LX switching every clock cycle) we require that:
I(A VDD _load) > D*(1-D)*V IN /(2*L*F OSC )
ISL97522
DRVP
FBP
NPN
CASCODE
TRANSISTOR
Q3
V ON
where the duty cycle, D = (A VDD - V IN )/A VDD
For example, with V IN = 5V, F OSC = 1.0MHz and A VDD =
12V we find continuous operation of the boost converter can
be guaranteed for:
L = 10μH and I(A VDD ) > 61mA
L = 6.8μH and I(A VDD ) > 89mA
L = 3.3μH and I(A VDD ) > 184mA
Buck Converter
FIGURE 19. CASCODE NPN TRANSISTOR CONFIGURATION
FOR HIGH CHARGE PUMP OUTPUT VOLTAGE
(>36V)
The buck converter is the step down converter, which
supplies the current to the logic circuit of the LCD system. In
the continuous current mode, the relationship between input
voltage and output voltage is as following:
LX
0.1μF
V LOGIC
0.1μF
A VDD
-------------------- = D
V IN
(EQ. 16
3k Ω
DRVP
Q3
0.1μF
0.1μF
V ON
Where D is the duty cycle of the switching MOSFET.
ISL97522
FBP
0.47μF
0.1μF
(>36V)
0.22μF
Because D is always less than 1, the output voltage of buck
converter is lower than input voltage.
T he Feedback Resistors
The buck converter output voltage is determined by the
following equation:
V LOGIC = --------------------------- × V FBL
FIGURE 20. THE LINEAR REGULATOR CONTROLS ONE
STAGE OF CHARGE PUMP
R 12 + R 13
R 13
(EQ. 17)
Where R12 and R13 are the feedback resistors of buck
Discontinuous/Continuous Boost Operation and
its Effect on the Charge Pumps
The ISL97522 V ON and V OFF architecture uses LX
switching edges to drive diode charge pumps from which
LDO regulators generate the V ON and V OFF supplies. It can
be appreciated that should a regular supply of LX switching
edges be interrupted, for example during discontinuous
operation at light A VDD boost load currents, then this may
affect the performance of V ON and V OFF regulation -
depending on their exact loading conditions at the time.
converter to set the output voltage Current drawn by the
resistor network should be limited to maintain the overall
converter efficiency. The maximum value of the resistor
network is limited by the feedback input bias current and the
potential for noise being coupled into the feedback pin. A
resistor network in the order of 300 Ω is recommended.
Buck Converter Input Capacitor
The capacitor should support the maximum AC RMS current
which happens when D = 0.5 and maximum output current.
To optimize V ON /V OFF regulation, the boundary of
I acrms ( C IN ) =
D ? ( 1 – D ) ? I O
(EQ. 18)
discontinuous/continuous operation of the boost converter
can be adjusted, by suitable choice of inductor given V IN ,
V OUT , switching frequency and the A VDD current loading, to
be in continuous operation.
15
Where I O is the output current of the buck converter.
FN7445.0
December 13, 2006
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| ISL97536IUZ | 功能描述:IC REG BUCK SYNC ADJ 1A 10MSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- 类型:降压（降压） 输出类型:两者兼有 输出数:1 输出电压:5V，1 V ~ 10 V 输入电压:3.5 V ~ 28 V PWM 型:电流模式 频率 - 开关:220kHz ~ 1MHz 电流 - 输出:600mA 同步整流器:无 工作温度:-40°C ~ 125°C 安装类型:表面贴装 封装/外壳:16-SSOP（0.154"，3.90mm 宽） 包装:带卷 (TR) 供应商设备封装:16-QSOP |
| ISL97536IUZ-T | 功能描述:IC REG BUCK SYNC ADJ 1A 10MSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:50 系列:- 类型:升压（升压） 输出类型:可调式 输出数:1 输出电压:5 V ~ 25 V 输入电压:2.3 V ~ 5.5 V PWM 型:电流模式 频率 - 开关:600kHz，1.2MHz 电流 - 输出:1A 同步整流器:无 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:8-TSSOP，8-MSOP（0.118"，3.00mm 宽） 包装:管件 供应商设备封装:8-MSOP |
| ISL97536IUZ-TK | 功能描述:IC REG BUCK SYNC ADJ 1A 10MSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:50 系列:- 类型:升压（升压） 输出类型:可调式 输出数:1 输出电压:5 V ~ 25 V 输入电压:2.3 V ~ 5.5 V PWM 型:电流模式 频率 - 开关:600kHz，1.2MHz 电流 - 输出:1A 同步整流器:无 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:8-TSSOP，8-MSOP（0.118"，3.00mm 宽） 包装:管件 供应商设备封装:8-MSOP |
| ISL97631HTZ-T7A | 制造商:Intersil Corporation 功能描述: |
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