参数资料
型号: MAX1778EUG+T
厂商: Maxim Integrated Products
文件页数: 21/39页
文件大小: 0K
描述: IC DCDC CONV MULTI OUT 24TSSOP
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: 2.7 V ~ 5.5 V
输出数: 5
输出电压: 2.7 V ~ 13 V
工作温度: 0°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 24-TSSOP(0.173",4.40mm 宽)
供应商设备封装: 24-TSSOP
包装: 带卷 (TR)
MAX1778/MAX1880–MAX1885
Quad-Output TFT LCD DC/DC
Converters with Buffer
The switching waveforms appear noisy and asynchro-
nous when light loading causes pulse-skipping opera-
tion; this is a normal operating condition that improves
light-load efficiency.
Dual Charge-Pump Regulator (MAX1778/
MAX1880–MAX1882 Only)
The MAX1778/MAX1880–MAX1882 controllers contain
two independent low-power charge pumps (Figure 4).
One charge pump inverts the input voltage and pro-
vides a regulated negative output voltage. The second
charge pump doubles the input voltage and provides a
regulated positive output voltage. The controllers
contain internal p-channel and n-channel MOSFETs to
control the power transfer. The internal MOSFETs
switch at a constant frequency (fCHP = fOSC/2).
I PEAK
Positive Charge Pump
During the first half-cycle, the n-channel MOSFET turns
TIME
I LOAD
on and charges flying capacitor C X(POS) (Figure 4).
This initial charge is controlled by the variable
n-channel on-resistance. During the second half-cycle,
the n-channel MOSFET turns off and the p-channel
t ON
t OFF
MOSFET turns on, level shifting C X(POS) by V SUPP volts.
This connects C X(POS) in parallel with the reservoir
capacitor C OUT(POS) . If the voltage across C OUT(POS)
plus a diode drop (V POS + V DIODE ) is smaller than the
Figure 3. Discontinuous-to-Continuous Conduction Crossover
Point
level-shifted flying capacitor voltage (V CX(POS) +
V SUPP ), charge flows from C X(POS) to C OUT(POS) until
the diode (D3) turns off.
MAX1778
MAX1880
MAX1881
V SUPP
SUPP
MAX1882
SUPN
V SUPN
2.7V TO 13V
OSC
2.7V TO 13V
V SUPD
D2
C X(POS)
DRVP
DRVN
C X(NEG)
D4
D3
D5
V POS
R3
FBP
FBN
R5
V NEG
C OUT(POS)
C OUT(NEG)
R4
V REF
1.25V
REF
R6
1 R3
V POS = ( + R4 ) V REF
GND
PGND
C REF
0.22 μ F
R5
V NEG = - ( R6 ) V REF
V REF = 1.25V
Figure 4. Low-Power Charge Pump Block Diagram
Maxim Integrated
V REF = 1.25V
21
相关PDF资料
PDF描述
RYM25DRSN-S288 CONN EDGECARD 50POS .156 EXTEND
SIP21106DR-46-E3 IC REG LDO 4.6V .15A SC70-5
35USC33000MEFCSN35X50 CAP ALUM 33000UF 35V 20% SNAP-IN
X40420V14I-CT1 IC VOLT MON DUAL SUP/SW 14-TSSOP
X40415S8-CT1 IC VOLTAGE MON DUAL W/SUP 8-SOIC
相关代理商/技术参数
参数描述
MAX1778EVKIT 功能描述:电源管理IC开发工具 MAX1778/80/81/82 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
MAX1779EUE 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT
MAX1779EUE+ 功能描述:直流/直流开关转换器 Triple-Output TFT LCD RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT
MAX1779EUE+T 功能描述:直流/直流开关转换器 Triple-Output TFT LCD RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT
MAX1779EUE-T 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT