- 您现在的位置：买卖IC网 > PDF目录80189 > LTC3108EDE#PBF (LINEAR TECHNOLOGY CORP) 0.45 A SWITCHING REGULATOR, PDSO12 PDF资料下载
参数资料
| 型号： | LTC3108EDE#PBF |
| 厂商： | LINEAR TECHNOLOGY CORP |
| 元件分类： | 稳压器 |
| 英文描述： | 0.45 A SWITCHING REGULATOR, PDSO12 |
| 封装： | 4 X 3 MM, LEAD FREE, PLASTIC, MO-229WGED, DFN-12 |
| 文件页数： | 2/22页 |
| 文件大小： | 1300K |
| 代理商： | LTC3108EDE#PBF |
LTC3108
0
3108fa
In a typical application, a storage capacitor (typically a few
hundred microfarads) is connected to VOUT. As soon as
VAUX exceeds 2.5V, the VOUT capacitor will be allowed to
charge up to its regulated voltage. The current available
to charge the capacitor will depend on the input voltage
and transformer turns ratio, but is limited to about 4.5mA
typical.
PGOOD
A power good comparator monitors the VOUT voltage.
The PGD pin is an open-drain output with a weak pull-up
(1MΩ)totheLDOvoltage.OnceVOUThaschargedtowithin
7.5% of its regulated voltage, the PGD output will go high.
If VOUT drops more than 9% from its regulated voltage,
PGD will go low. The PGD output is designed to drive a
microprocessor or other chip I/O and is not intended to
drive a higher current load such as an LED. Pulling PGD
up externally to a voltage greater than VLDO will cause a
small current to be sourced into VLDO. PGD can be pulled
low in a wire-OR configuration with other circuitry.
VOUT2
VOUT2 is an output that can be turned on and off by the
host, using the VOUT2_EN pin. When enabled, VOUT2 is
connected to VOUT through a 1.3 P-channel MOSFET
switch. This output, controlled by a host processor, can
be used to power external circuits such as sensors and
amplifiers,thatdo nothavea lowpower sleepor shutdown
capability. VOUT2 can be used to power these circuits only
when they are needed.
Minimizing the amount of decoupling capacitance on
VOUT2willallowittobeswitchedonandofffaster,allowing
shorter burst times and, therefore, smaller duty cycles in
pulsed applications such as a wireless sensor/transmit-
ter. A small VOUT2 capacitor will also minimize the energy
that will be wasted in charging the capacitor every time
VOUT2 is enabled.
VOUT2 has a soft-start time of about 5s to limit capacitor
chargingcurrentandminimizeglitchingofthemainoutput
when VOUT2 is enabled. It also has a current limiting circuit
that limits the peak current to 0.3A typical.
The VOUT2 enable input has a typical threshold of 1V
with 100mV of hysteresis, making it logic-compatible. If
VOUT2_EN (which has an internal pull-down resistor) is
low, VOUT2 will be off. Driving VOUT2_EN high will turn on
the VOUT2 output.
Note that while VOUT2_EN is high, the current limiting cir-
cuitry for VOUT2 draws an extra 8A of quiescent current
from VOUT. This added current draw has a negligible effect
on the application and capacitor sizing, since the load on
the VOUT2 output, when enabled, is likely to be orders of
magnitude higher than 8A.
VSTORE
The VSTORE output can be used to charge a large storage
capacitor or rechargeable battery after VOUT has reached
regulation.OnceVOUThasreachedregulation,theVSTORE
output will be allowed to charge up to the VAUX voltage.
The storage element on VSTORE can be used to power
the system in the event that the input source is lost, or
is unable to provide the current demanded by the VOUT,
VOUT2 and LDO outputs. If VAUX drops below VSTORE,
the LTC3108 will automatically draw current from the stor-
age element. Note that it may take a long time to charge
a large capacitor, depending on the input energy available
and the loading on VOUT and VLDO.
Since the maximum current from VSTORE is limited to a
few milliamps, it can safely be used to trickle-charge NiCd
or NiMH rechargeable batteries for energy storage when
the input voltage is lost. Note that the VSTORE capacitor
cannot supply large pulse currents to VOUT. Any pulse load
on VOUT must be handled by the VOUT capacitor.
Short-Circuit Protection
All outputs of the LTC3108 are current limited to protect
against short-circuits to ground.
Output Voltage Sequencing
A timing diagram showing the typical charging and
voltage sequencing of the outputs is shown in Figure 1.
Note: time not to scale.
operaTion
相关PDF资料 |
PDF描述 |
|---|---|
| LM2575-05IKTGR | 3.2 A SWITCHING REGULATOR, 63 kHz SWITCHING FREQ-MAX, PSSO5 |
| LM3700XCBP-308/NOPB | 1-CHANNEL POWER SUPPLY SUPPORT CKT, PBGA9 |
| LDS9003002-T2 | SWITCHING CONTROLLER, PQCC16 |
| LT6109HMS-1#PBF | SPECIALTY ANALOG CIRCUIT, PDSO10 |
| L296HT | 7.5 A SWITCHING REGULATOR, 200 kHz SWITCHING FREQ-MAX, PZFM15 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC3108EDETRPBF | 制造商:LINER 制造商全称:Linear Technology 功能描述:Ultralow Voltage Step-Up Converter and Power Manager |
| LTC3108EDE-TRPBF | 制造商:LINER 制造商全称:Linear Technology 功能描述:Ultralow Voltage Step-Up Converter and Power Manager |
| LTC3108EGN | 制造商:LINER 制造商全称:Linear Technology 功能描述:Ultralow Voltage Step-Up Converter and Power Manager |
| LTC3108EGN#PBF | 功能描述:IC CONV BOOST PROG 4.5MA 16SSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 电源管理 - 专用 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:50 系列:- 应用:热电冷却器 电流 - 电源:- 电源电压:3 V ~ 5.5 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:28-SOIC（0.173"，4.40mm 宽）裸露焊盘 供应商设备封装:28-TSSOP 裸露焊盘 包装:管件 产品目录页面:1410 (CN2011-ZH PDF) |
| LTC3108EGN#PBF | 制造商:Linear Technology 功能描述:BOOST DC/DC CONVERTER IC 制造商:Linear Technology 功能描述:IC, STEP-UP CONVERTER, SSOP-16 |
发布紧急采购，3分钟左右您将得到回复。