購買 30KPA84 | 30KPA84數據表 | Heisener.com
聯繫我們
SalesDept@heisener.com +86-755-83210559 ext. 809

30KPA84

30KPA84

30KPA84

僅供參考

零件編號 30KPA84
製造商 Littelfuse Inc.
描述 TVS DIODE 84VWM 146.16VC AXIAL
數據表

30KPA84 數據表

封裝 P600, Axial
ECAD
庫存 8,010 piece(s)
單價 Request a Quote
交貨期 待確認
預計送達時間 十一月 24 - 十一月 29 (選擇速遞服務)
請求報價
支付方式
送貨服務
  • 我們提供的 30KPA84 具有全球市場競爭力的價格,如有需要請發送詢價單給我們。謝謝!
  • 添加 30KPA84 及其數量至BOM以便提交您的報價請求。 Heisener.com 無需註冊便可以提交 30KPA84 的報價請求。

30KPA84參數

製造商Littelfuse Inc.
類別電路保護 - TVS - 二極體
封裝P600, Axial
ECAD
系列30KPA
類型Zener
單向通道1
雙向通道-
電壓 - 反向支座(典型值)84V
電壓 - 擊穿(最小)88.64V
電壓 - 箝位(最大值)@ Ipp146.16V
電流 - 峰值脈衝(10 /1000μs)217.7A
功率 - 峰值脈衝30000W (30kW)
電力線保護No
應用General Purpose
電容@頻率-
工作溫度-55°C ~ 175°C (TJ)
安裝類型Through Hole
包/箱P600, Axial
供應商設備包P600

30KPA84數據表

30KPA84 Packaging

Customized Labels
Sealing
Packing
Insepction

30KPA84 FAQ

  • 1. How to order 30KPA84 on Heisener?
    Currently, Heisener only provide peer-to-peer order processing. While you submit the RFQ, our professional agent will contact you with the competitive prices in the global market, and our agent will prompt you to finish the order if you accept our offers.
  • 2. How does Heisener guarantee that 30KPA84 is from the original manufacturer or authorized agents?
    We have a professional and experienced quality control team to strictly verify and test the 30KPA84. All suppliers must pass our qualification reviews before they can publish their products including 30KPA84 on Heisener; we pay more attention to the channels and quality of 30KPA84 products than any other customer. We strictly implement supplier audits, so you can purchase with confidence.
  • 3. Are the 30KPA84 price and inventory displayed accurate?
    The price and inventory of 30KPA84 fluctuates frequently and cannot be updated in time, it will be updated periodically within 24 hours. And, our quotation usually expires after 5 days.
  • 4. What forms of payment are accepted?
    Wire Transfer, PayPal, Alipay, Wechat, Credit Card, Western Union, MoneyGram, and Escrow are all acceptable.
    Warm Tips: Some orders in certain payment forms may require handling fee.
  • 5. How is the shipping arranged?
    Customers can choose industry-leading freight companies, including DHL, UPS, FedEx, TNT, and Registered Mail. Shipping insurance is also available.
    Once your order has been processed for shipment, our salesperson will send you an email advising you of the shipping status and tracking number.
    Warm Tips: It may take up to 24 hours for the carriers to display tracking information. Usually, express delivery takes 3-5 days, and registered mail takes 25-60 days.
  • 6. What is the process for return or replacement of 30KPA84?
    All goods will implement Pre-Shipment Inspection (PSI), selected at random from all batches of your order to do a systematic inspection before arranging the shipment. If there is something wrong with the 30KPA84 we delivered, we will accept the replacement or return of the 30KPA84 only when all of the below conditions are fulfilled:
    (1)Such as a deficiency in quantity, delivery of wrong items, and apparent external defects (breakage and rust, etc.), and we acknowledge such problems.
    (2)We are informed of the defect described above within 90 days after the delivery of 30KPA84.
    (3)The PartNo is unused and only in the original unpacked packaging.
    Two processes to return the products:
    (1)Inform us within 90 days
    (2)Obtain Requesting Return Authorizations
  • 7.How to contact us to get technical supports, such as 30KPA84 pin diagram, 30KPA84 datasheet?
    If you need any after-sales service, please do not hesitate to contact us.

30KPA84相關產品

USV1A330MFD USV1A330MFD Nichicon, CAP ALUM 33UF 20% 10V RADIAL, Radial, Can, 30KPA 查看
Y00074K00000F9L Y00074K00000F9L Vishay Foil Resistors (Division of Vishay Precision Group), RES 4K OHM 0.6W 1% RADIAL, Radial, 30KPA 查看
MCR01MRTF9092 MCR01MRTF9092 Rohm Semiconductor, RES SMD 90.9K OHM 1% 1/16W 0402, 0402 (1005 Metric), 30KPA 查看
1331R-334J 1331R-334J API Delevan Inc., FIXED IND 330UH 53MA 16 OHM SMD, 2-SMD, 30KPA 查看
CLT-117-02-F-D-BE-A-P CLT-117-02-F-D-BE-A-P Samtec Inc., 2MM SOCKET STRIPS, -, 30KPA 查看
87589-3 87589-3 TE Connectivity AMP Connectors, CONN HEADER VERT .100 14POS TIN, -, 30KPA 查看
315610050550871+ 315610050550871+ AVX Corp/Kyocera Corp, CONN COMPACT FLASH CARD R/A SMD, -, 30KPA 查看
3-84534-7 3-84534-7 TE Connectivity AMP Connectors, CONN FFC VERT 37POS 1.25MM PCB, -, 30KPA 查看
GEM22DRMI-S288 GEM22DRMI-S288 Sullins Connector Solutions, CONN EDGE DUAL FMALE 44POS 0.156, -, 30KPA 查看
51448-XX001 51448-XX001 Amphenol FCI, HDR PWRBLADE, -, 30KPA 查看
VE-JTW-MZ-F2 VE-JTW-MZ-F2 Vicor Corporation, CONVERTER MOD DC/DC 5.5V 25W, Half Brick, 30KPA 查看
XC9236G37DER-G XC9236G37DER-G Torex Semiconductor Ltd, 600MA SYNCHRONOUS STEP-DOWN DCDC, -, 30KPA 查看

30KPA84 保證

Service Guarantee

服務保證

我們保證100%的客戶滿意度。

我們經驗豐富的銷售團隊和技術支持團隊支持我們的服務以滿足所有客戶。

Quality Guarantee

質量保證

我們提供90天保修。

如果您收到的物品質量不合格,我們將負責您的退款或更換,但物品必須以原始狀態退回。

全球供應鏈-可靠的授權分銷商資源

零件編號 製造商 描述 庫存

30KPA84CAE3/TR13

D# V36:1790_09104492

Microchip Technology Inc

TVS Diode Single Bi-Dir 84V 30KW 2-Pin Case R-6 T/R

RoHS: Compliant
0

30KPA84CA-B

D# V36:1790_06420646

Littelfuse Inc

TVS Diode Single Bi-Dir 84V 30KW 2-Pin Case P-600 Bulk

0

30KPA84CA

D# V72:2272_21386258

Suzhou Good-Ark Electronics Co Ltd

TVS Diode Single Bi-Dir 84V 30KW 2-Pin Case P-600

RoHS: Compliant
0

30KPA84A

D# V72:2272_21386402

Suzhou Good-Ark Electronics Co Ltd

TVS Diode Single Uni-Dir 84V 30KW 2-Pin Case P-600

RoHS: Compliant
0
零件編號 製造商 描述 庫存

30KPA84CAE3/TR13

D# 30KPA84CAE3/TR13

Microchip Technology Inc

30000W, STAND-OFF VOLTAGE = 84V, 5%, BI-DIR - Tape and Reel (Alt: 30KPA84CAE3/TR13)

RoHS: Compliant
0

30KPA84A/TR13

D# 30KPA84A/TR13

YAGEO Corporation

Transient Voltage Suppressor Uni-Directional 84V 30kW 2-Pin Axial Leaded T/R - Tape and Reel (Alt: 30KPA84A/TR13)

RoHS: Not Compliant
0

30KPA84CE3/TR13

D# 30KPA84CE3/TR13

Microchip Technology Inc

30000W, STAND-OFF VOLTAGE = 84V, 10%, BI-DIR - Tape and Reel (Alt: 30KPA84CE3/TR13)

RoHS: Compliant
0

30KPA84CA/B

D# 30KPA84CA/B

YAGEO Corporation

Transient Voltage Suppressor Bi-Directional 84V 30kW 2-Pin Axial Leaded Box - Boxed Product (Development Kits) (Alt: 30KPA84CA/B)

RoHS: Not Compliant
0

30KPA84AE3/TR13

D# 30KPA84AE3/TR13

Microchip Technology Inc

Diode TVS Single Uni-Directional 43V 30000W 2-Pin P600 Tape and Reel - Tape and Reel (Alt: 30KPA84AE3/TR13)

RoHS: Compliant
0

30KPA84E3/TR13

D# 30KPA84E3/TR13

Microchip Technology Inc

30000W, STAND-OFF VOLTAGE = 84V, 10%, UNI-DIR - Tape and Reel (Alt: 30KPA84E3/TR13)

RoHS: Compliant
0

30KPA84CA/TR13

D# 30KPA84CA/TR13

YAGEO Corporation

Transient Voltage Suppressor Bi-Directional 84V 30kW 2-Pin Axial Leaded T/R - Tape and Reel (Alt: 30KPA84CA/TR13)

RoHS: Not Compliant
0

30KPA84A/B

D# 30KPA84A/B

YAGEO Corporation

Transient Voltage Suppressor Uni-Directional 84V 30kW 2-Pin Axial Leaded Box - Boxed Product (Development Kits) (Alt: 30KPA84A/B)

RoHS: Not Compliant
0
零件編號 製造商 描述 庫存

30KPA84A

New Jersey Semiconductor Products, Inc.

500

30KPA84C

New Jersey Semiconductor Products, Inc.

500

30KPA84

New Jersey Semiconductor Products, Inc.

500

30KPA84CA

New Jersey Semiconductor Products, Inc.

500
零件編號 製造商 描述 庫存

30KPA84AE3/TR13

Microsemi Corporation

30000W, STAND-OFF VOLTAGE = 84V, ? 5%, UNI-DIR - Tape and Reel

0

30KPA84C

Littelfuse Inc

TVS DIODE, FULL REEL, TVS Polarity:Bidirectional, Reverse Stand-Off Voltage Vrwm:84V, Breakdown Voltage Min:93.8V, Breakdown Voltage Max:93.8V, Clamping Voltage Vc Max:139.2V, Peak Pulse Current Ippm:217.7A, No. of Pins:2, MSL:- , RoHS Compliant: Yes

0

30KPA84C-B

Littelfuse Inc

TVS DIODE 84VWM 146.16VC P600

0

30KPA84

Littelfuse Inc

TVS DIODE 84VWM 139.2VC AXIAL

0

30KPA84CA

Littelfuse Inc

TVS DIODE, FULL REEL, TVS Polarity:Bidirectional, Reverse Stand-Off Voltage Vrwm:84V, Breakdown Voltage Min:93.8V, Breakdown Voltage Max:93.8V, Clamping Voltage Vc Max:139.2V, Peak Pulse Current Ippm:217.7A, No. of Pins:2, MSL:- , RoHS Compliant: Yes

0

30KPA84-B

Littelfuse Inc

TVS DIODE 84VWM 146.16VC P600

0

30KPA84CAE3/TR13

Microsemi Corporation

30000W, STAND-OFF VOLTAGE = 84V, ? 5%, BI-DIR - Tape and Reel

0

30KPA84A

Littelfuse Inc

TVS DIODE 84VWM 139.2VC AXIAL

0

30KPA84A-B

Littelfuse Inc

TVS DIODE 84VWM 139.2VC P600

0

30KPA84CE3/TR13

Microsemi Corporation

30000W, STAND-OFF VOLTAGE = 84V, ? 10%, BI-DIR - Tape and Reel

0

30KPA84CA-B

Littelfuse Inc

TVS DIODE 84VWM 139.2VC P600

0

30KPA84E3/TR13

Microsemi Corporation

30000W, STAND-OFF VOLTAGE = 84V, ? 10%, UNI-DIR - Tape and Reel

0
零件編號 製造商 描述 庫存

30KPA84A

BrightKing Inc

P600 TVS RoHS

26

30KPA84CA

BrightKing Inc

Bidirectional 84V 93.8V 139.2V 217.7A P600 TVS RoHS

296
零件編號 製造商 描述 庫存

30KPA84CA

D# 30KPA84CA-ND

Littelfuse Inc

TVS DIODE 84V 139.2V P600

0

30KPA84-B

D# 30KPA84-B-ND

Littelfuse Inc

TVS DIODE 84V 146.16V P600

0

30KPA84CAE3/TR13

D# 30KPA84CAE3/TR13-ND

Microchip Technology Inc

TVS DIODE 84V 139.2V P600

0

30KPA84A-B

D# 30KPA84A-B-ND

Littelfuse Inc

TVS DIODE 84V 139.2V P600

0

30KPA84A-HRA

D# 30KPA84A-HRA-ND

Littelfuse Inc

TVS DIODE 84V 139.2V P600

0

30KPA84CE3/TR13

D# 30KPA84CE3/TR13-ND

Microchip Technology Inc

TVS DIODE 84V P600

0

30KPA84C

D# 30KPA84C-ND

Littelfuse Inc

TVS DIODE 84V 146.16V P600

0

30KPA84CA-B

D# 30KPA84CA-B-ND

Littelfuse Inc

TVS DIODE 84V 139.2V P600

0

30KPA84

D# 30KPA84-ND

Littelfuse Inc

TVS DIODE 84V 146.16V P600

0

30KPA84CA-HR

D# 30KPA84CA-HR-ND

Littelfuse Inc

TVS DIODE 84V 139.2V P600

0

30KPA84AE3/TR13

D# 30KPA84AE3/TR13-ND

Microchip Technology Inc

TVS DIODE 84V 139.2V P600

0

30KPA84CA-HRA

D# 30KPA84CA-HRA-ND

Littelfuse Inc

TVS DIODE 84V 139.2V P600

0

30KPA84E3/TR13

D# 30KPA84E3/TR13-ND

Microchip Technology Inc

TVS DIODE 84V P600

0

30KPA84A

D# 30KPA84ACT-ND

Littelfuse Inc

TVS DIODE 84V 139.2V P600

192

30KPA84A-HR

D# 30KPA84A-HR-ND

Littelfuse Inc

TVS DIODE 84V 139.2V P600

0

30KPA84C-B

D# 30KPA84C-B-ND

Littelfuse Inc

TVS DIODE 84V 146.16V P600

0
零件編號 製造商 描述 庫存

30KPA84CA-B

Littelfuse Inc

ESD Suppressors / TVS Diodes TVS Hi-Power Diode Axial

RoHS: Compliant
pbFree: Yes
0

30KPA84CA

Littelfuse Inc

30KPA Series 8 W 103.18 V Bi-Directional Through Hole TVS Diode - P-600

RoHS: Compliant
pbFree: Yes
1600
零件編號 製造商 描述 庫存

30KPA84C

New Jersey Semiconductor Products Inc

OEM/CM QUOTES ONLY | NO BROKERS

988

30KPA84

New Jersey Semiconductor Products Inc

OEM/CM QUOTES ONLY | NO BROKERS

974

30KPA84A

OEM/CM QUOTES ONLY | NO BROKERS

5650
零件編號 製造商 描述 庫存

30KPA84CA

Suzhou Good-Ark Electronics Co Ltd

5000

30KPA84A

Suzhou Good-Ark Electronics Co Ltd

5000
零件編號 製造商 描述 庫存

30KPA84A

D# C522492

BrightKing Inc

26

30KPA84CA

D# C522493

BrightKing Inc

296
零件編號 製造商 描述 庫存

30KPA84CA-B

D# 576-30KPA84CA-B

Littelfuse Inc

ESD Suppressors / TVS Diodes TVS Hi-Power Diode Axial

RoHS: Compliant
145

30KPA84A

D# 576-30KPA84A

Littelfuse Inc

ESD Suppressors / TVS Diodes TVS Hi Power Diode 30KPA Axial

RoHS: Compliant
641

30KPA84CA

D# 576-30KPA84CA

Littelfuse Inc

ESD Suppressors / TVS Diodes TVS Hi Power Diode 30KPA Axial

RoHS: Compliant
29
零件編號 製造商 描述 庫存

30KPA84CE3/TR13

Microchip Technology Inc

TVS

RoHS: Compliant
0

30KPA84E3/TR13

Microchip Technology Inc

TVS

RoHS: Compliant
0

30KPA84AE3/TR13

Microchip Technology Inc

TVS

RoHS: Compliant
0

30KPA84CAE3/TR13

Microchip Technology Inc

TVS

RoHS: Compliant
0
零件編號 製造商 描述 庫存

30KPA84AE3/TR13

D# MCHP00000047596

Microchip Technology Inc

TVS

0

30KPA84CE3/TR13

D# MCHP00000047598

Microchip Technology Inc

TVS

0

30KPA84CA

D# XSFP00000205974

Littelfuse Inc

1600

30KPA84E3/TR13

D# MCHP00000047599

Microchip Technology Inc

TVS

0

30KPA84CAE3/TR13

D# MCHP00000047597

Microchip Technology Inc

TVS

0
零件編號 製造商 描述 庫存

30KPA84-B

D# 91T4119

Littelfuse Inc

TVS AXIAL LEAD HIGH POWER - BULK / BULK

RoHS: Not Compliant
Min Qty: 100
Container: Bulk
0

30KPA84

D# 32M4565

Littelfuse Inc

TRANSIENT SUPPRESSOR DIODE,SINGLE,UNIDIRECTIONAL,84V V(RWM),Axial-9.1

RoHS: Not Compliant
Min Qty: 800
Container: TAPE & REEL - FULL
0

30KPA84CA-B

D# 91T4122

Littelfuse Inc

TVS AXIAL LEAD HIGH POWER - BULK / BULK

RoHS: Not Compliant
Min Qty: 100
Container: Bulk
0

30KPA84A-B

D# 91T4120

Littelfuse Inc

TVS AXIAL LEAD HIGH POWER - BULK / BULK

RoHS: Not Compliant
Min Qty: 100
Container: Bulk
0

30KPA84A-HRA

D# 50Y0903

Littelfuse Inc

HI-REL TVS AXIAL HIGH POWER 30KW / TR

RoHS: Not Compliant
Min Qty: 800
Container: TAPE & REEL - FULL
0

30KPA84CA-HR

D# 50Y0904

Littelfuse Inc

HI-REL TVS AXIAL HIGH POWER 30KW / TR

RoHS: Not Compliant
Min Qty: 800
Container: TAPE & REEL - FULL
0

30KPA84CA-HRA

D# 50Y0905

Littelfuse Inc

HI-REL TVS AXIAL HIGH POWER 30KW / TR

RoHS: Not Compliant
Min Qty: 800
Container: TAPE & REEL - FULL
0

30KPA84A

D# 32M4566

Littelfuse Inc

TVS DIODE, TVS Polarity:Unidirectional, Reverse Stand-Off Voltage Vrwm:84V, Breakdown Voltage Range:93.8V, Clamping Voltage Vc Max:139.2V, Peak Pulse Current Ippm:217.7A, Diode Case Style:Axial Leaded, No. of Pins:2 RoHS Compliant: Yes

RoHS: Compliant
Min Qty: 800
Container: TAPE & REEL - FULL
0

30KPA84A-HR

D# 50Y0902

Littelfuse Inc

HI-REL TVS AXIAL HIGH POWER 30KW / TR

RoHS: Not Compliant
Min Qty: 800
Container: TAPE & REEL - FULL
0

30KPA84C-B

D# 91T4121

Littelfuse Inc

TVS AXIAL LEAD HIGH POWER - BULK / BULK

RoHS: Not Compliant
Min Qty: 100
Container: Bulk
0

30KPA84C

D# 32M4567

Littelfuse Inc

TRANSIENT SUPPRESSOR DIODE,SINGLE,BIDIRECTIONAL,84V V(RWM),Axial-9.1

RoHS: Not Compliant
Min Qty: 800
Container: TAPE & REEL - FULL
0

30KPA84CA

D# 32M4568

Littelfuse Inc

TVS DIODE, FULL REEL, Product Range:30KPA Series, TVS Polarity:Bidirectional, Reverse Stand-Off Voltage Vrwm:84V, Clamping Voltage Vc Max:139.2V, Diode Case Style:Axial Leaded, No. of Pins:2Pins, Breakdown Voltage Min:93.8V RoHS Compliant: Yes

RoHS: Compliant
Min Qty: 800
Container: TAPE & REEL - FULL
0
零件編號 製造商 描述 庫存

30KPA84C-B

D# NS-30KPA84C-B

Littelfuse Inc

OEM/CM ONLY

6394

30KPA84CA

D# NS-30KPA84CA

Littelfuse Inc

OEM/CM ONLY

6539

30KPA84C

D# NS-30KPA84C

Littelfuse Inc

OEM/CM ONLY

2643

30KPA84

D# NS-30KPA84

Littelfuse Inc

OEM/CM ONLY

1783

30KPA84-B

D# NS-30KPA84-B

Littelfuse Inc

OEM/CM ONLY

7294

30KPA84A

D# NS-30KPA84A

Littelfuse Inc

OEM/CM ONLY

4457

30KPA84CAE3/TR13

D# NS-30KPA84CAE3/TR13

Microsemi Commercial Components Group

OEM/CM ONLY

9631

30KPA84A-B

D# NS-30KPA84A-B

Littelfuse Inc

OEM/CM ONLY

3417

30KPA84CA-B

D# NS-30KPA84CA-B

Littelfuse Inc

OEM/CM ONLY

9479

30KPA84E3/TR13

D# NS-30KPA84E3/TR13

Microsemi Commercial Components Group

OEM/CM ONLY

4862

30KPA84CE3/TR13

D# NS-30KPA84CE3/TR13

Microsemi Commercial Components Group

OEM/CM ONLY

7895

30KPA84AE3/TR13

D# NS-30KPA84AE3/TR13

Microsemi Commercial Components Group

OEM/CM ONLY

2897
零件編號 製造商 描述 庫存

30KPA84CA

Littelfuse Inc

OEM/CM ONLY

919

30KPA84CAB

Littelfuse Inc

OEM/CM ONLY

106

30KPA84C

Littelfuse Inc

OEM/CM ONLY

890

30KPA84

Littelfuse Inc

OEM/CM ONLY

878

30KPA84A

Littelfuse Inc

OEM/CM ONLY

744
零件編號 製造商 描述 庫存

30KPA84CA

Littelfuse Inc

ESD Suppressors / TVS Diodes TVS Hi Power Diode 30KPA Axial

0

30KPA84CA-B

Littelfuse Inc

ESD Suppressors / TVS Diodes TVS Hi-Power Diode Axial

0
零件編號 製造商 描述 庫存

30KPA84CA

D# 30653481

Suzhou Good-Ark Electronics Co Ltd

TVS Diode Single Bi-Dir 84V 30KW 2-Pin Case P-600

RoHS: Compliant
0

30KPA84A

D# 30175220

Suzhou Good-Ark Electronics Co Ltd

TVS Diode Single Uni-Dir 84V 30KW 2-Pin Case P-600

RoHS: Compliant
0

Quick Inquiry

30KPA84

質量認證

黑森爾對質量的承諾,塑造了我們的採購、測試、運輸流程以及它們之間的每一步。這個基準是我們所銷售的每一個元器件的基礎。

ISO9001:2015, ICAS, IAF, UKAS

查看證書

聯繫我們

您有關於 30KPA84 的問題嗎?

30KPA84 QRCode

掃描以查看此頁面

推薦產品

AUIRF1010ZS

MOSFET N-CH 55V 75A D2PAK

744043101

FIXED IND 100UH 510MA 600 MOHM

XC18V04PCG44C

IC PROM REPROGR 4MB 44-PLCC

ICE3BR0665J

IC OFFLINE CTRLR SMPS OTP 8DIP

IRLML9301TRPBF

MOSFET P-CH 30V 3.6A SOT-23-3

LT1763CS8-3.3#PBF

IC REG LINEAR 3.3V 500MA 8SOIC

ASDMB-48.000MHZ-LC-T

OSC MEMS 48.000MHZ CMOS SMD

LTC1844ES5-2.5#TRMPBF

IC REG LIN 2.5V 150MA TSOT23-5

TDA2040V

IC AMP AUDIO PWR HIFI PENTAWATT5

LV8548MC-AH

IC MOTOR DRIVER PAR MFP10S

更多 »

30KPA84 Tags

  • 30KPA84
  • 30KPA84 PDF
  • 30KPA84 數據表
  • 30KPA84 規格
  • 30KPA84 圖片
  • Littelfuse Inc.
  • Littelfuse Inc. 30KPA84
  • 買30KPA84
  • 30KPA84 價格
  • 30KPA84 經銷商
  • 30KPA84 供應商
  • 30KPA84 批發

30KPA84可用於