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参数资料
| 型号： | MAX8753ETI+T |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 17/20页 |
| 文件大小： | 0K |
| 描述： | IC DC-DC CONV TFT LCD 28TQFN |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 2,500 |
| 应用： | 转换器，TFT，LCD |
| 输入电压： | 2.6 V ~ 5.5 V |
| 输出数： | 4 |
| 输出电压： | 2.6 V ~ 13 V |
| 工作温度： | 0°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 28-WFQFN 裸露焊盘 |
| 供应商设备封装： | 28-TQFN-EP（5x5） |
| 包装： | 带卷 (TR) |
TFT LCD DC-DC Converter with
Integrated Charge Pumps
R 1 = R 2 × ? MAIN ? 1 ?
Rectifier Diode
The MAX8753 ’ s high switching frequency demands a
high-speed rectifier. Schottky diodes are recommend-
ed for most applications because of their fast recovery
time and low forward voltage. In general, a 2A Schottky
diode complements the internal MOSFET well.
Output-Voltage Selection
The output voltage of the main step-up regulator can be
adjusted by connecting a resistive voltage-divider from
the output (V MAIN ) to GND with the center tap connected
to FB (see Figure 1). Select R2 in the 10k ? to 50k ?
range. Calculate R1 with the following equation:
? V ?
? V FB ?
where V FB , the step-up regulator ’ s feedback set point,
is 1.245V. Place R1 and R2 close to the IC.
Loop Compensation
For stability, add a pole-zero pair from FB to GND in the
form of a series resistor (R COMP ) and capacitor
(C COMP ). R COMP should be approximately half the
value of the R2 feedback resistor. To further optimize
transient response, vary R COMP in 20% steps and
C COMP in 50% steps while observing transient
response waveforms.
Charge-Pump Regulators
Output Voltage Selection
Adjust the positive charge-pump regulator output volt-
age by connecting a resistive voltage-divider from the
regulator output V POS to GND with the center tap con-
where V REF = 1.25V, and V FBN = 250mV is the regula-
tion point of the negative charge-pump regulator.
Flying Capacitor
Increasing the flying capacitor (C X ) value lowers the
effective source impedance and increases the output-
current capability of the charge pump. Increasing the
capacitance indefinitely has a negligible effect on out-
put-current capability because the internal switch resis-
tance and the diode impedance place a lower limit on
the source impedance. A 0.1μF ceramic capacitor
works well in most low-current applications. The flying
capacitor ’ s voltage rating must exceed the following:
V C 1 > V SUPP
V C 2 > 2 V SUPP
V C 3 > V SUPN
V C 4 > 2 V SUPN , if used
Charge-Pump Input Capacitor
Use an input capacitor on SUPP and SUPN with a value
equal to or greater than the flying capacitors on that
charge pump. Place the capacitors as close to SUPP
and SUPN as possible. Connect the capacitors directly
to PGND.
Charge-Pump Output Capacitor
Increasing the output capacitance or decreasing the
ESR reduces the output ripple voltage and the peak-to-
peak transient voltage. With ceramic capacitors, the
output-voltage ripple is dominated by the capacitance
value. Use the following equation to approximate the
required capacitor value:
nected to FBP (Figure 1). Select the lower resistor of
the divider R6 in the 10k ? to 50k ? range. Calculate
upper resistor R5 with the following equation:
C OUT _ CP ≥
I LOAD _ CP
2 f OSC V RIPPLE _ CP
R 5 = R 6 × ? POS ? 1 ?
R 3 = R 4 × FBN NEG
? V ?
? V FBP ?
where V FBP = 1.25V (typ) is the regulation point of the
positive charge-pump regulator.
Adjust the negative charge-pump regulator output volt-
age by connecting a resistive voltage-divider from the
negative charge-pump output V NEG to REF with the
center tap connected to FBN (Figure 1). Select R4 in
the 20k ? to 100k ? range. Calculate R3 with the follow-
ing equation:
V ? V
V REF ? V FBN
where C OUT_CP is the output capacitor of the charge
pump, I LOAD_CP is the load current of the charge
pump, and V RIPPLE_CP is the desired peak-to-peak
value of the output ripple.
Charge-Pump Rectifier Diode
Use low-cost silicon switching diodes for D2 and D3
with a current rating equal to or greater than two times
the average charge-pump input current. If it helps
avoid an extra stage, some or all of the diodes can be
replaced with Schottky diodes with an equivalent cur-
rent rating.
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相关代理商/技术参数 |
参数描述 |
|---|---|
| MAX8753EVKIT | 功能描述:电源管理IC开发工具 MAX8753 Eval Kit RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V |
| MAX8756ETI+ | 功能描述:电流和电力监控器、调节器 Interleaved Dual Power-Supply Ctlr RoHS:否 制造商:STMicroelectronics 产品:Current Regulators 电源电压-最大:48 V 电源电压-最小:5.5 V 工作温度范围:- 40 C to + 150 C 安装风格:SMD/SMT 封装 / 箱体:HPSO-8 封装:Reel |
| MAX8756ETI+T | 功能描述:电流和电力监控器、调节器 Interleaved Dual Power-Supply Ctlr RoHS:否 制造商:STMicroelectronics 产品:Current Regulators 电源电压-最大:48 V 电源电压-最小:5.5 V 工作温度范围:- 40 C to + 150 C 安装风格:SMD/SMT 封装 / 箱体:HPSO-8 封装:Reel |
| MAX8757ETG+ | 制造商:Maxim Integrated Products 功能描述:INTERLEAVED HI-EFF AND DUAL PS CNTRLR 24TQFN EP - Rail/Tube |
| MAX8757ETI+ | 制造商:Rochester Electronics LLC 功能描述: 制造商:Maxim Integrated Products 功能描述: |
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