参数资料
| 型号： | MIC2826-A0YMT TR |
| 厂商： | Micrel Inc |
| 文件页数： | 23/27页 |
| 文件大小： | 0K |
| 描述： | IC PWR MANAGER PROG 4OUT 14-TMLF |
| 特色产品： | MIC2826 Quad Output PMIC |
| 标准包装： | 1 |
| 应用： | 处理器 |
| 电源电压： | 2.7 V ~ 5.5 V |
| 工作温度： | -40°C ~ 125°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 14-UFQFN 裸露焊盘，14-TMLF? |
| 供应商设备封装： | 14-TMLF?（2.5x2.5） |
| 包装： | 标准包装 |
| 产品目录页面： | 1086 (CN2011-ZH PDF) |
| 其它名称： | 576-3529-6 |
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页第15页第16页第17页第18页第19页第20页第21页第22页当前第23页第24页第25页第26页第27页
I PEAK = ? I OUT + V OUT ?
? ?
?
Micrel, Inc.
Application Information
The Micrel MIC2826 is a four output, programmable
Power Management IC, optimized for high efficiency
power support. The device integrates a single 500mA
PWM/PFM synchronous buck (step-down) regulator with
three Low Dropout Regulators and an I2C interface that
provides programmable Dynamic Voltage Scaling (DVS),
Power Sequencing, and individual output Enable/Disable
controls allowing the user to optimally control all four
outputs.
Input Capacitors
A 4.7μF ceramic capacitor is recommended on the DVIN
pin for bypassing. X5R or X7R dielectrics are
recommended for the input capacitor. Y5V dielectrics
lose most of their capacitance over temperature and are
therefore not recommended. Also, tantalum and
electrolytic capacitors alone are not recommended
because of their reduced RMS current handling,
reliability, and ESR increases.
An additional 0.1μF is recommended close to the DVIN
and DGND pins for high frequency filtering. Smaller case
size capacitors are recommended due to their lower
ESR and ESL.
Minimum 1.0μF ceramic capacitors are recommended
on the LDO1IN and LDO23IN pins for bypassing.
Please refer to layout recommendations for proper
layout of the input capacitors.
Output Capacitors
The MIC2826 is designed for a 2.2μF or greater ceramic
output capacitor for the DC-DC converter and 1.0μF for
the LDO regulators. Increasing the output capacitance
will lower output ripple and improve load transient
response but could increase solution size or cost. A low
equivalent series resistance (ESR) ceramic output
capacitor such as the TDK C1608X5R0J475K, size
MIC2826
The MIC2826 was designed for use with an inductance
range from 0.47μH to 4.7μH. Typically, a 1μH inductor is
recommended for a balance of transient response,
efficiency and output ripple. For faster transient
response a 0.47μH inductor may be used. For lower
output ripple, a 4.7μH is recommended.
Proper selection should ensure the inductor can handle
the maximum average and peak currents required by the
load. Maximum current ratings of the inductor are
generally given in two methods; permissible DC current
and saturation current. Permissible DC current can be
rated either for a 40°C temperature rise or a 10% to 20%
loss in inductance. Ensure the inductor selected can
handle the maximum operating current. When saturation
current is specified, make sure that there is enough
margin that the peak current will not saturate the
inductor. Peak current can be calculated as follows:
? ? 1 ? V OUT /V IN ? ?
? 2 × f × L ? ?
As shown by the previous calculation, the peak inductor
current is inversely proportional to the switching
frequency and the inductance; the lower the switching
frequency or the inductance the higher the peak current.
As input voltage increases, the peak current also
increases.
The size of the inductor depends on the requirements of
the application. Refer to the Application Circuit and Bill of
Material for details.
DC resistance (DCR) is also important. While DCR is
inversely proportional to size, DCR can represent a
significant efficiency loss. Refer to the Efficiency
Considerations.
Efficiency Considerations
Efficiency is defined as the amount of useful output
power, divided by the amount of power supplied.
Efficiency % = ? ? OUT
? ? × 100
0603, 4.7μF ceramic capacitor is recommended based
upon performance, size and cost. X5R or X7R dielectrics
are recommended for the output capacitor. Y5V
? V × I OUT
? V IN × I IN
?
?
dielectrics lose most of their capacitance over
temperature and are therefore not recommended.
In addition to a 4.7μF, a small 0.1μF is recommended
close to the load for high frequency filtering. Smaller
case size capacitors are recommended due to their
lower equivalent series ESR and ESL.
Inductor
Inductor selection will be determined by the following
(not necessarily in the order of importance);
Maintaining high efficiency serves two purposes. It
reduces power dissipation in the power supply, reducing
the need for heat sinks and thermal design
considerations and it reduces consumption of current for
battery powered applications. Reduced current draw
from a battery increases the devices operating time and
is critical in hand held devices.
There are two types of losses in switching converters;
DC losses and switching losses. DC losses are simply
the power dissipation of I 2 R. Power is dissipated in the
?
?
?
?
Inductance
Rated current value
Size requirements
DC resistance (DCR)
high side switch during the on cycle. Power loss is equal
to the high side MOSFET R DSON multiplied by the Switch
Current squared. During the off cycle, the low side N-
channel MOSFET conducts, also dissipating power.
Device operating current also reduces efficiency. The
July 2009
23
M9999-071609-A
相关PDF资料 |
PDF描述 |
|---|---|
| MIC28500YJL TR | IC REG BUCK SYNC ADJ 4A 28MLF |
| MIC28510YJL TR | IC REG BUCK SYNC ADJ 4A 28MLF |
| MIC29152WD TR | IC REG LDO ADJ 1.5A TO-252-5 |
| MIC2920A-12WS | IC REG LDO 12V .4A SOT-223 |
| MIC29302AWU TR | IC REG LDO ADJ 3A TO-263-5 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MIC2826-D9YMT TR | 功能描述:直流/直流开关调节器 Single 500mA Step-Down and Triple 150mA LDOs with I2C Voltage Control & Sequencing RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5 |
| MIC2826-D9YMT-TR | 功能描述:Processor PMIC 14-TMLF? (2.5x2.5) 制造商:microchip technology 系列:- 包装:剪切带（CT） 零件状态:停产 应用:处理器 电流 - 电源:- 电压 - 电源:2.7 V ~ 5.5 V 工作温度:-40°C ~ 125°C 安装类型:表面贴装 封装/外壳:14-UFQFN 裸露焊盘，14-TMLF? 供应商器件封装:14-TMLF?（2.5x2.5） 标准包装:1 |
| MIC2827-B2YMT TR | 功能描述:直流/直流开关调节器 Single 500mA Step-Down and Dual 150mA LDOs with I2C Voltage Control & Sequencing RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5 |
| MIC2827-B2YMT-TR | 功能描述:Processor PMIC 14-TMLF? (2.5x2.5) 制造商:microchip technology 系列:- 包装:剪切带（CT） 零件状态:停产 应用:处理器 电流 - 电源:- 电压 - 电源:2.7 V ~ 5.5 V 工作温度:-40°C ~ 125°C 安装类型:表面贴装 封装/外壳:14-UFQFN 裸露焊盘，14-TMLF? 供应商器件封装:14-TMLF?（2.5x2.5） 标准包装:1 |
| MIC2827-E1YMT TR | 功能描述:直流/直流开关调节器 Single 500mA Step-Down and Dual 150mA LDOs with I2C Voltage Control & Sequencing RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5 |
发布紧急采购，3分钟左右您将得到回复。