Electronic Components Datasheet Search |
|
SY58621L Datasheet(PDF) 11 Page - Micrel Semiconductor |
|
SY58621L Datasheet(HTML) 11 Page - Micrel Semiconductor |
11 / 20 page Micrel, Inc. SY58621L January 2006 11 M9999-012006-B hbwhelp@micrel.com or (408) 955-1690 Detailed Description Receiver The receiver AC-coupled differential input distributes data to 3.2Gbps with signals as small as 10mV (20mVPP) or as large as 900mV (1.8VPP). The receiver input features an internal 50Ω input termination connected to an internal reference which optimizes the inputs for AC-coupled signals. Input signals are linearly amplified with 38dB of differential gain and the output signal is limited to 400mV (800mVPP). The receiver output buffer features 50Ω source termination resistors and a current source that provides 400mV (800mVPP) swing into 50Ω termination. The output buffers terminates to standard CML loads (100Ω across the output pair or equivalent). See the “Output Stage Receiver” section for more details. Transmitter The transmitter differential input includes Micrel’s unique, patented 3-pin input termination architecture that directly interfaces to any (AC- or DC-coupled) differential signal as small as 100mV (200mVPP) without any termination resistor network in the signal path. The transmitter output buffer terminates to standard LVPECL loads (RL = 50_ to VCC_TXQ-2V). The output buffer is a special variable swing LVPECL buffer controlled by TXVCTRL. The output buffer features emitter follower output that provides 80mV (160mVPP) to 800mV (1.6VPP) swing into 50_ transmission lines. See the next section and Figures 1a and 1b for more details on how to control the variable output swing feature. Figure 1a. Voltage Source Implementation Figure 1b. Alternative Implementation Transmitter PECL Variable-Swing Output Buffer ∑ Connecting VREF_CTRL to TXVCTRL sets the transmitter output buffer to maximum swing ∑ Setting TXVCTRL to VCC_TXQ, sets the transmitter output buffer to minimum swing ∑ Control of the transmitter output swing buffers can be obtained by using a variable resistor connected between VREF_CTRL and VCC_TXQ with a wiper connected to TXVCTRL as shown in Figure 1b Receiver LOS The SY58621L features a chatter-free Loss-of-Signal (LOS) TTL compatible output with an internal 4.75kΩ pull-up resistor. LOS circuitry monitors the input receiver signal and asserts a signal when the input signal falls below the threshold set by the programmable LOS level set pin (LOSLVL). When the amplitude of the receiver input signal falls below the threshold, LOS is asserted HIGH with a response time of ~0.2uS. LOS can be fed into /RXEN to maintain output stability by disabling the output during a Loss- of-Signal condition. Figure 2a and 2b shows the LOS connection to /RXEN. When /RXEN is HIGH, the output signal RXQ is held LOW and /RXQ is held HIGH. Typically, 2dB of LOS hysteresis is adequate to prevent the receiver output from chattering. LOS operation is optimized for data rates ≥622Mbps with an input receiver amplitude of at least 10mV (20mVPP). Due to the long time constant in slower data rates below 622Mbps, the SY58621L LOS function does not guarantee chatter-free operation for low amplitude signals. LOSLVL sets the threshold of the LOS input amplitude detection. Connecting an external resistor, RLOSLVL, |
Similar Part No. - SY58621L |
|
Similar Description - SY58621L |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.NET |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List 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 |