参数资料
型号: SMARTPSE24-KIT
厂商: Silicon Laboratories Inc
文件页数: 5/36页
文件大小: 0K
描述: KIT EVAL REF 24PORT SPI/UART
标准包装: 1
主要目的: 电源管理,以太网供电(POE),PSE
已用 IC / 零件: Si3452,Si3482,Si3500
已供物品: 板,线缆,CD
相关产品: SI3482-A01-GM-ND - IC CTLR POE 24-48PORT PSE 24-QFN
336-1830-5-ND - IC POE CONTROLLER MIDSPAN 40QFN
336-1835-5-ND - IC POE CONTROLLER MIDSPAN 40QFN
336-1829-5-ND - IC POE CONTROLLER MIDSPAN 40QFN
336-1831-5-ND - IC POE CONTROLLER MIDSPAN 40QFN
336-1834-5-ND - IC POE CONTROLLER MIDSPAN 40QFN
336-1844-5-ND - IC POE SWITCH PWR OVER LAN 20QFN
336-1833-5-ND - IC POE CONTROLLER MIDSPAN 40QFN
336-1832-5-ND - IC POE CONTROLLER MIDSPAN 40QFN
Si3452
Rev. 1.3
13
4.2. Classification
Following a successful PD detection, the classification phase will be automatically initiated in all operational
modes. During this phase, a single measurement will be made at 18 V to determine how much power the PD
device will draw under maximum loads per the IEEE 802.3af and 802.3at standards. The current limit during this
test mode is 60 mA nominal.
The Si3452 supports 1-Event and 2-Event classification. When operating in PoE (<15.4 W) mode, 1-Event
classification is used. Operation in PoE+ (>15.4 W) mode results in 2-Event classification probes. The 1-Event
classification is compliant to IEEE standard 802.3-2005. 2-Event classification is compliant to draft IEEE P802.3at.
4.3. Port Turn-On and Power FETs
The FET is turned on with a gate drive that results in a very low-noise turn-on waveform with a slew rate of less
than 1 V/sec (See Figure 5).
The power FET switch on each port has been sized to have a typical ON resistance of approximately 0.3
. The
shunt resistor for current measurement has also been set to 0.1
. Including interconnection and process variation,
the total resistance to VEE for a port that is on is 0.6
(max). This limits the maximum power dissipation per
channel to < 250 mW when the operating current is 600 mA, the maximum current allowed by the IEEE 802.3at
PoE+ standard.
The FET has a programmable operating current limit. Each channel can be set to support output currents of
400 mA or 800 mA minimum.
In addition to the normal current limit, there is a short circuit current shutdown approximately 25% greater than the
nominal current limit. If there is a transient current surge where the current ramps up faster than the programmed
current limit can respond, the gate drive voltage is clamped immediately to VEE. The clamp is enabled for at least
10 s, which allows the normal current circuitry to respond.
Another important protection feature is foldback current limiting. When VOUT is near VEE, the current limit is at
maximum. As the VDS of the driver switch increases (and VOUT is closer to ground), the current limit goes to its
lowest level. The amount of the foldback current is scaled proportionally with the programmed current limit.
Figure 5. Turn-On Waveform—Vport Relative to GND
相关PDF资料
PDF描述
LBC2518T681M INDUCTOR WOUND 680UH 45MA 1007
VE-24D-EX CONVERTER MOD DC/DC 85V 75W
1SMA5926BT3 DIODE ZENER 11V 1.5W SMA
ST16C2550CQ-0B-EB EVAL BOARD FOR ST16C2551 48TQFP
9-6278032-5 C/A MT-RJ/MT-RJ MM
相关代理商/技术参数
参数描述
SMARTRF06EBK 功能描述:射频开发工具 SMARTRF06 EVAL BRD RoHS:否 制造商:Taiyo Yuden 产品:Wireless Modules 类型:Wireless Audio 工具用于评估:WYSAAVDX7 频率: 工作电源电压:3.4 V to 5.5 V
SMARTRFTRXEBK 功能描述:EVAL BOARD SMART RF 制造商:texas instruments 系列:- 零件状态:有效 类型:收发器 频率:- 配套使用产品/相关产品:MSP430 所含物品:板,线缆 标准包装:1
SMARTSOCKET 575 TYPE D 制造商:TIME MARK CORP SIGNALINE 功能描述:Nominal input voltage 575VAC, Max input voltage 635VAC
SMARTSTART-BAC-D 制造商:IDEC Corporation 功能描述:PROGRAMMABLE LOGIC CONTROLLER, Accessory Type:Starter Kit, For Use With:FL1D Ser
SMARTSTART-BAC-E 制造商:IDEC Corporation 功能描述:FL1E SMARTRELAY STARTER KIT 120-240VAC/DC BASE MODULE W/O LCD DISPLAY 制造商:IDEC Corporation 功能描述:STARTER KIT, AUTOMATION & PROCESS CONTRO 制造商:IDEC Corporation 功能描述:STARTER KIT, AUTOMATION & PROCESS CONTROL; No. of Inputs:12; No. of Outputs:12; Kit Contents:WindLGC 6.0 Software, FL1E-B12RCC and Serial Programming Cable; Supply Voltage Max:240VAC; Accessory Type:SmartRelay Starter Kit 制造商:IDEC Corporation 功能描述:FL1E-B12RCC, Windlgc Software And Programming Cable 制造商:IDEC CORPORATION 功能描述:FL1E SmartRelay Starter Kit