LTC4257 IEEE 802.3af PD Power over Ethernet Interface Controller
The LTC®4257 provides complete signature and power interface functions for a device operating in an IEEE 802.3af Power over Ethernet (PoE) system. The LTC4257 simplifies Powered Device (PD) design by incorporating the 25k signature resistor, the classification current source, input current limit with thermal foldback, undervoltage lockout and power good signalling, all in a single 8-pin package. By incorporating a high voltage power MOSFET onboard, the LTC4257 provides the system designer with reduced cost while also saving board space.
The LTC4257 can interface directly with a variety of linear Technology DC/DC converter products to provide a cost effective power solution for IP phones, wireless access points and other PDs. linear Technology also provides solutions for Power Sourcing Equipment (PSE) applications with quad network power controllers.
The LTC4257 is available in the 8-pin SO and low profile (3mm x 3mm) DFN packages
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LTC4257 订购信息和价格参考Package Variations and Pricing
| 器件型号 | 封装 | 引脚 | 温度 | 价格 (以 1 ~ 99 片为批量) | 价格 (以 1000 片为批量) * |
| LTC4257CDD | DFN | 8 | C | $2.41 | $1.70 |
| LTC4257CDD#PBF | DFN | 8 | C | $2.41 | $1.70 |
| LTC4257CDD#TR | DFN | 8 | C | $1.76 | |
| LTC4257CDD#TRPBF | DFN | 8 | C | $1.76 | |
| LTC4257CDD-1 | DFN | 8 | C | $2.59 | $1.85 |
| LTC4257CDD-1#PBF | DFN | 8 | C | $2.59 | $1.85 |
| LTC4257CDD-1#TR | DFN | 8 | C | $1.91 | |
| LTC4257CDD-1#TRPBF | DFN | 8 | C | $1.91 | |
| LTC4257CS8 | SO | 8 | C | $2.32 | $1.65 |
| LTC4257CS8#PBF | SO | 8 | C | $2.32 | $1.65 |
| LTC4257CS8#TR | SO | 8 | C | $1.71 | |
| LTC4257CS8#TRPBF | SO | 8 | C | $1.71 | |
| LTC4257CS8-1 | SO | 8 | C | $2.50 | $1.75 |
| LTC4257CS8-1#PBF | SO | 8 | C | $2.50 | $1.75 |
| LTC4257CS8-1#TR | SO | 8 | C | $1.81 | |
| LTC4257CS8-1#TRPBF | SO | 8 | C | $1.81 | |
| LTC4257IDD | DFN | 8 | I | $2.77 | $1.95 |
| LTC4257IDD#PBF | DFN | 8 | I | $2.77 | $1.95 |
| LTC4257IDD#TR | DFN | 8 | I | $2.01 | |
| LTC4257IDD#TRPBF | DFN | 8 | I | $2.01 | |
| LTC4257IDD-1 | DFN | 8 | I | $2.95 | $2.10 |
| LTC4257IDD-1#PBF | DFN | 8 | I | $2.95 | $2.10 |
| LTC4257IDD-1#TR | DFN | 8 | I | $2.16 | |
| LTC4257IDD-1#TRPBF | DFN | 8 | I | $2.16 | |
| LTC4257IS8 | SO | 8 | I | $2.68 | $1.90 |
| LTC4257IS8#PBF | SO | 8 | I | $2.68 | $1.90 |
| LTC4257IS8#TR | SO | 8 | I | $1.96 | |
| LTC4257IS8#TRPBF | SO | 8 | I | $1.96 | |
| LTC4257IS8-1 | SO | 8 | I | $2.86 | $2.00 |
| LTC4257IS8-1#PBF | SO | 8 | I | $2.86 | $2.00 |
| LTC4257IS8-1#TR | SO | 8 | I | $2.06 | |
| LTC4257IS8-1#TRPBF | SO | 8 | I | $2.06 |
LTC4257 数据手册及相关资料下载
- 数据手册(英文) : LTC4257 - IEEE 802.3af PD Power over Ethernet Interface Controller.PDF
- 可靠性数据 : R413 Reliability Data .PDF
- 产品选型卡 : LTPoE++ Controllers.PDF
