- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄373328 > RT9702 Power Management/Switchers PDF資料下載
參數(shù)資料
| 型號(hào)： | RT9702 |
| 英文描述： | Power Management/Switchers |
| 中文描述： | 電源管理/切換器 |
| 文件頁數(shù)： | 12/16頁 |
| 文件大?。?/td> | 240K |
| 代理商： | RT9702 |
RT9702/A
Preliminary
www.richtek.com
12
DS9702A-01 March 2003
1.5A for RT9702A respectively. When a heavy load or
short circuit is applied to an enabled switch, a large
transient current may flow until the current limit circuitry
responds. Once this current limit threshold is exceeded
the device enters constant current mode until the
thermal shutdown occurs or the fault is removed.
Thermal Shutdown
Thermal shutdown is employed to protect the device
from damage if the die temperature exceeds approxi-
mately 130°C. If enabled, the switch automatically
restarts when the die temperature falls 20°C. The
output and FLG signal will continue to cycle on and off
until the device is disabled or the fault is removed.
Power Dissipation
The device’s junction temperature depends on several
factors such as the load, PCB layout, ambient
temperature and package type. The output pin of
RT9702/A can deliver a current of up to 500mA, and
1.1A respectively over the full operating junction
temperature range. However, the maximum output
current must be derated at higher ambient temperature
to ensure the junction temperature does not exceed
100
°
C. With all possible conditions, the junction
temperature must be within the range specified under
operating conditions. Power dissipation can be
calculated based on the output current and the R
DS(ON)
of switch as below.
P
D
= R
DS(ON)
x I
OUT
2
Although the devices are rated for 500mA and 1.1A of
output current, but the application may limit the amount
of output current based on the total power dissipation
and the ambient temperature. The final operating
junction temperature for any set of conditions can be
estimated by the following thermal equation:
P
D (MAX)
= ( T
J (MAX)
T
A
) /
θ
JA
Where T
J (MAX)
is the maximum junction temperature of
the die (100
°
C) and T
A
is the maximum ambient
temperature. The junction to ambient thermal
resistance (
θ
JA
)
for SOT-25 package at recommended
minimum footprint is 250
°
C/W (
θ
JA
is layout
dependent).
Universal Serial Bus (USB) & Power Distribution
The goal of USB is to be enabled device from different
vendors to interoperate in an open architecture. USB
features include ease of use for the end user, a wide
range of workloads and applications, robustness,
synergy with the PC industry, and low-cost implement-
ation. Benefits include self-identifying peripherals,
dynamically attachable and reconfigurable peripherals,
multiple connections (support for concurrent operation
of many devices), support for as many as 127 physical
devices, and compatibility with PC Plug-and-Play
architecture.
The Universal Serial Bus connects USB devices with a
USB host: each USB system has one USB host. USB
devices are classified either as hubs, which provide
additional attachment points to the USB, or as functions,
which provide capabilities to the system (for example, a
digital joystick). Hub devices are then classified as
either Bus-Power Hubs or Self-Powered Hubs.
A Bus-Powered Hub draws all of the power to any
internal functions and downstream ports from the USB
connector power pins. The hub may draw up to 500mA
from the upstream device. External ports in a
Bus-Powered Hub can supply up to 100mA per port,
with a maximum of four external ports.
Self-Powered Hub power for the internal functions and
downstream ports does not come from the USB,
although the USB interface may draw up to 100mA
from its upstream connect, to allow the interface to
function when the remainder of the hub is powered
down. The hub must be able to supply up to 500mA on
all of its external downstream ports. Please refer to
Universal Serial Specification Revision 2.0 for more
details on designing compliant USB hub and host
systems.
Over-Current protection devices such as fuses and
PTC resistors (also called polyfuse or polyswitch) have
slow trip times, high on-resistance, and lack the
necessary circuitry for USB-required fault reporting.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| RT9702A | Power Management/Switchers |
| RT9801A | Power Management/Voltage Dector |
| RT9801B | Power Management/Voltage Dector |
| RT9802A | Power Management/Voltage Dector |
| RT9802B | Power Management/Voltage Dector |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| RT9702_11 | 制造商:RICHTEK 制造商全稱:Richtek Technology Corporation 功能描述:80m??, 500mA/1.1A High Side Power Switches with Flag |
| RT9702A | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Power Management/Switchers |
| RT9702AGB | 功能描述:IC PWR SW USB 1.5A SOT23-5 RoHS:是 類別:集成電路 (IC) >> PMIC - 電源分配開關(guān) 系列:- 特色產(chǎn)品:XRP252 Switches 標(biāo)準(zhǔn)包裝:1 系列:- 類型:高端開關(guān) 輸出數(shù):2 Rds（開）:140 毫歐 內(nèi)部開關(guān):是 電流限制:1.15A 輸入電壓:1.75 V ~ 5.5 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:10-WFDFN 裸露焊盤 供應(yīng)商設(shè)備封裝:10-TDFN（3x3） 包裝:Digi-Reel® 其它名稱:1016-1691-6 |
| RT9702AGJ5 | 功能描述:IC PWR SW USB 1.1A TSOT-23-5 RoHS:是 類別:集成電路 (IC) >> PMIC - 電源分配開關(guān) 系列:- 特色產(chǎn)品:XRP252 Switches 標(biāo)準(zhǔn)包裝:1 系列:- 類型:高端開關(guān) 輸出數(shù):2 Rds（開）:140 毫歐 內(nèi)部開關(guān):是 電流限制:1.15A 輸入電壓:1.75 V ~ 5.5 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:10-WFDFN 裸露焊盤 供應(yīng)商設(shè)備封裝:10-TDFN（3x3） 包裝:Digi-Reel® 其它名稱:1016-1691-6 |
| RT9702APB | 制造商:RICHTEK 制造商全稱:Richtek Technology Corporation 功能描述:80mヘ, 500mA/1.1A High-Side Power Switches with Flag |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。