参数资料
型号: MIC5268-1.2YM5 TR
厂商: Micrel Inc
文件页数: 6/8页
文件大小: 0K
描述: IC REG LDO 1.2V .15A SOT23-5
标准包装: 1
稳压器拓扑结构: 正,固定式
输出电压: 1.2V
输入电压: 2.7 V ~ 6 V
稳压器数量: 1
电流 - 输出: 150mA
电流 - 限制(最小): 160mA
工作温度: -40°C ~ 125°C
安装类型: 表面贴装
封装/外壳: SC-74A,SOT-753
供应商设备封装: SOT-23-5
包装: 标准包装
产品目录页面: 1100 (CN2011-ZH PDF)
其它名称: 576-2836-6
P D(max) = ? ?
? T J(max) ? T A ?
?
Micrel, Inc.
Application Information
Enable/Shutdown
The MIC5268 comes with an active-high enable pin that
allows the regulator to be disabled. Forcing the enable
pin low disables the regulator and sends it into a “zero”
off-mode-current state. In this state, current consumed
by the regulator goes nearly to zero. Forcing the enable
pin high enables the output voltage. This part is CMOS
and the enable pin cannot be left floating; a floating
enable pin may cause an indeterminate state on the
output.
Input Capacitor
An input capacitor is not required for stability. A 1μF
input capacitor is recommended when the bulk ac supply
capacitance is more than 10 inches away from the
device, or when the supply is a battery.
Output Capacitor
The MIC5268 requires an output capacitor for stability.
The design requires 1μF or greater on the output to
maintain stability. The capacitor can be a low-ESR
ceramic chip capacitor. The MIC5268 has been
designed to work specifically with the low-cost, small
chip capacitors. Tantalum capacitors can also be used
for improved capacitance overtemperature. The value of
the capacitor can be increased without bound.
X7R dielectric ceramic capacitors are recommended
because of their temperature performance. X7R-type
capacitors change capacitance by 15% over their
operating temperature range and are the most stable
type of ceramic capacitors. Z5U and Y5V dielectric
capacitors change value by as much 50% and 60%
respectively over their operating temperature ranges. To
MIC5268
Transient Response
The MIC5268 implements a unique output stage to
dramatically improve transient response recovery time.
The output is a totem-pole configuration with a P-
channel MOSFET pass device and an N-channel
MOSFET clamp. The N-channel clamp is a significantly
smaller device that prevents the output voltage from
overshooting when a heavy load is removed. This
feature helps to speed up the transient response by
significantly decreasing transient response recovery time
during the transition from heavy load (100mA) to light
load (100μA).
Active Shutdown
The MIC5268 also features an active shutdown clamp,
which is an N-channel MOSFET that turns on when the
device is disabled. This allows the output capacitor and
load to discharge, de-energizing the load.
Thermal Considerations
The MIC5268 is designed to provide 150mA of
continuous current in a very small package. Maximum
power dissipation can be calculated based on the output
current and the voltage drop across the part. To
determine the maximum power dissipation of the
package, use the junction-to-ambient thermal resistance
of the device and the following basic equation:
?
? θ JA ?
T J(max) is the maximum junction temperature of the die,
125°C, and T A is the ambient operating temperature. θ JA
is layout dependent; Table 1 shows examples of
junction-to-ambient thermal resistance for the MIC5268.
use a ceramic chip capacitor withY5V dielectric, the
value must be much higher than an X7Rceramic or a
tantalum capacitor to ensure the same minimum
capacitance value over the operating temperature range.
Package
SOT-23-5 (M5)
θ JA Recommended
Minimum Footprint
235°C/W
θ JA 1” Square
Copper Clad
185°C/W
θ JC
145°C/W
P D(max) = ?
? 125 ° C ? 50 ° C ?
Tantalum capacitors have a very stable dielectric (10%
over their operating temperature range) and can also be
used with this device.
Power Good
The power good output is an open-drain output. It is
designed essentially to work as a power-on reset
generator once the regulated voltage was up and/or a
fault condition. The output of the power good drives low
when a fault condition AND an undervoltage detection
occurs. The power good output comes back up once the
output has reached 97% of its nominal value and a 1ms
to 5ms delay has passed. See Timing Diagram .
The MIC5268’s internal circuit intelligently monitors
overcurrent, overtemperature and dropout conditions
and ORs these outputs together indicate some fault
condition. This output is fed into an on-board delay
circuitry that drives the open drain transistor to indicate a
fault.
Table 1. Thermal Resistance
The actual power dissipation of the regulator circuit can
be determined using the equation:
P D = (V IN – V OUT ) I OUT + V IN I GND
Substituting P D(max) for P D and solving for the operating
conditions that are critical to the application will give the
maximum operating conditions for the regulator circuit.
For example, when operating the MIC5268-1.2BM5 at
50°C with a minimum footprint layout, the maximum
input voltage for a set output current can be determined
as follows:
?
? 235 ° C ?
P D(max) = 315mW
September 2006
6
M9999-091506
相关PDF资料
PDF描述
MIC5270-4.1YM5 TR IC REG LDO -4.1V .1A SOT23-5
MIC5271BM5 TR IC REG LDO NEG ADJ .1A SOT23-5
MIC5280YME TR IC REG LDO ADJ 25MA 8SOIC
MIC5281-5.0YMME TR IC REG LDO 5V 25MA 8MSOP-EP
MIC5282-5.0YMME IC REG LDO 5V 50MA 8EMSOP
相关代理商/技术参数
参数描述
MIC5270-3.0BM5 TR 功能描述:IC REG LDO -3V .1A SOT23-5 RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 系列:- 标准包装:500 系列:- 稳压器拓扑结构:正,固定式 输出电压:12V 输入电压:14.5 V ~ 35 V 电压 - 压降(标准):- 稳压器数量:1 电流 - 输出:500mA 电流 - 限制(最小):- 工作温度:-40°C ~ 125°C 安装类型:通孔 封装/外壳:TO-205AD,TO-39-3 金属罐 供应商设备封装:TO-39 包装:散装 其它名称:*LM78M12CH*LM78M12CH/NOPBLM78M12CH
MIC5270-3.0YM5 制造商:Micrel Inc 功能描述:IC REG LDO 100MA -3.0V SOT23-5*NIC*
MIC5270-3.0YM5 TR 功能描述:低压差稳压器 - LDO 100mA Negative uCap LDO Regulator(Lead Free) RoHS:否 制造商:Texas Instruments 最大输入电压:36 V 输出电压:1.4 V to 20.5 V 回动电压(最大值):307 mV 输出电流:1 A 负载调节:0.3 % 输出端数量: 输出类型:Fixed 最大工作温度:+ 125 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-20
MIC5270-3.0YM5TR 制造商:Micrel 功能描述:LDO Regulator Neg -3V 0.1A
MIC5270-3.0YM5-TR 功能描述:Linear Voltage Regulator IC Negative Fixed 1 Output -3V 100mA SOT-23-5 制造商:microchip technology 系列:- 包装:剪切带(CT) 零件状态:有效 稳压器拓扑:负,固定式 电压 - 输出:-3V 电流 - 输出:100mA 电压 - 跌落(典型值):0.5V @ 100mA 稳压器数:1 电压 - 输入:可下调至-16V 电流 - 限制(最小值):- 工作温度:-40°C ~ 125°C 安装类型:表面贴装 封装/外壳:SC-74A,SOT-753 供应商器件封装:SOT-23-5 标准包装:1