전자부품 데이터시트 검색엔진 |
|
LAN8710A-EZC 데이터시트(PDF) 38 Page - SMSC Corporation |
|
LAN8710A-EZC 데이터시트(HTML) 38 Page - SMSC Corporation |
38 / 82 page Small Footprint MII/RMII 10/100 Ethernet Transceiver with HP Auto-MDIX and flexPWR® Technology Datasheet Revision 1.4 (08-23-12) 38 SMSC LAN8710A/LAN8710Ai DATASHEET 3.7.4 REGOFF: Internal +1.2V Regulator Configuration The incorporation of flexPWR technology provides the ability to disable the internal +1.2V regulator. When the regulator is disabled, an external +1.2V must be supplied to the VDDCR pin. Disabling the internal +1.2V regulator makes it possible to reduce total system power, since an external switching regulator with greater efficiency (versus the internal linear regulator) can be used to provide +1.2V to the transceiver circuitry. Note: Because the REGOFF configuration strap shares functionality with the LED1 pin, proper consideration must also be given to the LED polarity. Refer to Section 3.8.1.1, "REGOFF and LED1 Polarity Selection," on page 39 for additional information on the relation between REGOFF and the LED1 polarity. 3.7.4.1 Disabling the Internal +1.2V Regulator To disable the +1.2V internal regulator, a pull-up strapping resistor should be connected from the REGOFF configuration strap to VDD2A. At power-on, after both VDDIO and VDD2A are within specification, the transceiver will sample REGOFF to determine whether the internal regulator should turn on. If the pin is sampled at a voltage greater than VIH, then the internal regulator is disabled and the system must supply +1.2V to the VDDCR pin. The VDDIO voltage must be at least 80% of the operating voltage level (1.44V when operating at 1.8V, 2.0V when operating at 2.5V, 2.64V when operating at 3.3V) before voltage is applied to VDDCR. As described in Section 3.7.4.2, when REGOFF is left floating or connected to VSS, the internal regulator is enabled and the system is not required to supply +1.2V to the VDDCR pin. 3.7.4.2 Enabling the Internal +1.2V Regulator The +1.2V for VDDCR is supplied by the on-chip regulator unless the transceiver is configured for the regulator off mode using the REGOFF configuration strap as described in Section 3.7.4.1. By default, the internal +1.2V regulator is enabled when REGOFF is floating (due to the internal pull-down resistor). During power-on, if REGOFF is sampled below VIL, then the internal +1.2V regulator will turn on and operate with power from the VDD2A pin. 3.7.5 nINTSEL: nINT/TXER/TXD4 Configuration The nINT, TXER, and TXD4 functions share a common pin. There are two functional modes for this pin, the TXER/TXD4 mode and nINT (interrupt) mode. The nINTSEL configuration strap is latched at POR and on the rising edge of the nRST. By default, nINTSEL is configured for nINT mode via the internal pull-up resistor. Note: Because the nINTSEL configuration strap shares functionality with the LED2 pin, proper consideration must also be given to the LED polarity. Refer to Section 3.8.1.2, "nINTSEL and LED2 Polarity Selection," on page 39 for additional information on the relation between nINTSEL and the LED2 polarity. |
유사한 부품 번호 - LAN8710A-EZC |
|
유사한 설명 - LAN8710A-EZC |
|
|
링크 URL |
개인정보취급방침 |
ALLDATASHEET.CO.KR |
ALLDATASHEET 가 귀하에 도움이 되셨나요? [ DONATE ] |
Alldatasheet는? | 광고문의 | 운영자에게 연락하기 | 개인정보취급방침 | 링크교환 | 제조사별 검색 All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |