- 您现在的位置：买卖IC网 > PDF目录80267 > LTC3554EPD#PBF (LINEAR TECHNOLOGY CORP) 0.6 A BATTERY CHARGE CONTROLLER, 2590 kHz SWITCHING FREQ-MAX, PQCC20 PDF资料下载
参数资料
| 型号： | LTC3554EPD#PBF |
| 厂商： | LINEAR TECHNOLOGY CORP |
| 元件分类： | 稳压器 |
| 英文描述： | 0.6 A BATTERY CHARGE CONTROLLER, 2590 kHz SWITCHING FREQ-MAX, PQCC20 |
| 封装： | 3 X 3 MM, LEAD FREE, PLASTIC, UTQFN-20 |
| 文件页数： | 15/36页 |
| 文件大小： | 418K |
| 代理商： | LTC3554EPD#PBF |
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页当前第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页
LTC3554/LTC3554-2
22
35542fb
In standby mode, each regulator operates hysteretically.
When the FB pin voltage falls below the internal 0.8V
reference, a current source from BVIN to SW turns on,
delivering current through the inductor to the switching
regulator output capacitor and load. When the FB pin
voltage rises above the reference plus a small hysteresis
voltage, that current is shut off. In this way, output regula-
tion is maintained.
Since the power transfer from BVIN to SW is through a
high impedance current source rather than through a low
impedance MOSFET switch, power loss scales with load
current as in a linear low dropout (LDO) regulator, rather
than as in a switching regulator. For near-zero load condi-
tions where regulator quiescent current is the dominant
power loss, standby mode is ideal. But at any appreciable
load current, Burst Mode operation yields the best overall
conversion efciency.
Shutdown
Each step-down switching regulator is shut down and
enabled via the pushbutton interface. In shutdown, each
switching regulator draws only a few nanoamps of leak-
age current from the BVIN pin. Each disabled regulator
also pulls down on its output with a 10k resistor from its
switch pin to ground.
Dropout Operation
It is possible for a step-down switching regulator’s input
voltage to fall near or below its programmed output volt-
age (e.g., a battery voltage of 3.4V with a programmed
output voltage of 3.3V). When this happens, the PMOS
switch duty cycle increases to 100%, keeping the switch on
OPERATION
continuously. Known as dropout operation, the respective
output voltage equals the regulator’s input voltage minus
the voltage drops across the internal P-channel MOSFET
and the inductor.
Soft-Start Operation
In normal operating mode, soft-start works by gradually
increasing the peak inductor current for each step-down
switching regulator over a 500μs period. This allows each
output to rise slowly, helping minimize the inrush current
needed to charge up the output capacitor. A soft-start cycle
occurs whenever a given switching regulator is enabled.
Soft-start occurs only in normal operation, but not in
standby mode. Standby mode operation is already in-
herently current-limited, since the regulator works by
intermittently turning on a current source from BVIN to
SW. Changing the state of the STBY pin while the regu-
lators are operating doesn’t trigger a new soft-start cycle,
to avoid glitching the outputs.
Frequency/Slew Rate Select
The FSEL pin allows an application to dynamically trade
off between highest efciency and reduced electromag-
netic interference (EMI) emission.
When FSEL is high, the switching regulator frequency is
set to 2.25MHz to stay out of the AM radio band. Also,
new patented circuitry is enabled which limits the slew rate
of the switch nodes (SW1 and SW2). This new circuitry
is designed to transition the switch node over a period of
a few nanoseconds, signicantly reducing radiated EMI
and conducted supply noise.
相关PDF资料 |
PDF描述 |
|---|---|
| LM4040A82IDCKT | 1-OUTPUT TWO TERM VOLTAGE REFERENCE, 8.192 V, PDSO6 |
| LT1021BMH-5#PBF | 1-OUTPUT THREE TERM VOLTAGE REFERENCE, 5 V, MBCY8 |
| LC015B | DC-DC REG PWR SUPPLY MODULE |
| LM385M-2.5X | 1-OUTPUT TWO TERM VOLTAGE REFERENCE, 2.5 V, PDSO8 |
| LM2575S-ADJTR | 3.2 A SWITCHING REGULATOR, 62 kHz SWITCHING FREQ-MAX, PSSO5 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC3554EPDTRPBF | 制造商:LINER 制造商全称:Linear Technology 功能描述:Micropower USB Power Manager with Li-Ion Charger and Two Step-Down Regulators |
| LTC3554EUD#PBF | 功能描述:IC USB POWER MANAGER 20UTQFN RoHS:是 类别:集成电路 (IC) >> PMIC - 电源管理 - 专用 系列:PowerPath™ 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) |
| LTC3554EUD#TRPBF | 功能描述:IC USB POWER MANAGER 20UTQFN RoHS:是 类别:集成电路 (IC) >> PMIC - 电源管理 - 专用 系列:PowerPath™ 标准包装:1 系列:- 应用:手持/移动设备 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:14-WFDFN 裸露焊盘 供应商设备封装:14-LLP-EP（4x4） 包装:Digi-Reel® 配用:LP3905SD-30EV-ND - BOARD EVALUATION LP3905SD-30 其它名称:LP3905SD-30DKR |
| LTC3554EUD-1#PBF | 功能描述:IC USB POWER MANAGER 20QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 电源管理 - 专用 系列:PowerPath™ 标准包装:1 系列:- 应用:手持/移动设备 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:14-WFDFN 裸露焊盘 供应商设备封装:14-LLP-EP（4x4） 包装:Digi-Reel® 配用:LP3905SD-30EV-ND - BOARD EVALUATION LP3905SD-30 其它名称:LP3905SD-30DKR |
| LTC3554EUD-1#TRPBF | 功能描述:IC USB POWER MANAGER 20QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 电源管理 - 专用 系列:PowerPath™ 标准包装:1 系列:- 应用:手持/移动设备 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:14-WFDFN 裸露焊盘 供应商设备封装:14-LLP-EP（4x4） 包装:Digi-Reel® 配用:LP3905SD-30EV-ND - BOARD EVALUATION LP3905SD-30 其它名称:LP3905SD-30DKR |
发布紧急采购，3分钟左右您将得到回复。