GTM Transceiver DC Input and Output Levels - GTM Transceiver DC Input and Output Levels - DS956

Versal Prime Series Data Sheet: DC and AC Switching Characteristics (DS956)
Document ID
DS956
Release Date
2025-03-14
Revision
1.15 English

The following table summarizes the DC specifications of the GTM transceivers in Versal Prime devices. Consult the Versal Adaptive SoC GTM Transceivers Architecture Manual (AM017) for further details.

Table 1. GTM Transceiver DC Specifications
Symbol DC Parameter Conditions Min Typ Max Units
DVPPIN Differential peak-to-peak input voltage (external AC coupled) PAM4 600 – 900 mV
NRZ 150 – 900 mV
DVPPOUT Differential peak-to-peak output voltage 1 Transmitter output swing is set to 1000100 800 – – mV
VCMOUTDC Common mode output voltage: DC (equation based) When remote RX is terminated to float TX output swing ≥ 800 mV VAVCCAUX – DVPPOUT/2 mV
TX output swing < 800 mV VAVTT – VVPPOUT/2 mV
When remote RX is terminated to VRX_TERM 2 TX output swing ≥ 800 mV VAVCCAUX – DVPPOUT/4 – (VAVCCAUX – VRX_TERM)/2 mV
TX output swing < 800 mV VAVTT – DVPPOUT/4 – (VAVTT – VRX_TERM)/2 mV
VCMOUTAC Common mode output voltage: AC coupled Equation based VAVCCAUX – DVPPOUT/2 mV
RIN Differential input resistance – 100 – Ω
ROUT Differential output resistance – 100 – Ω
TOSKEW Transmitter output pair (TXP and TXN) intra-pair skew – – 3.7 ps
CEXT Recommended external AC coupling capacitor 3 – 100 – nF
  1. The output swing and pre-emphasis levels are programmable using the GTM transceiver attributes discussed in the Versal Adaptive SoC GTM Transceivers Architecture Manual (AM017) and can result in values lower than reported in this table.
  2. VRX_TERM is the remote RX termination voltage. The VRX_TERM must be within 7% of the calculated value for VCMOUTDC terminated to float.
  3. Other values can be used as appropriate to conform to specific protocols and standards.
Figure 1. Single-Ended Peak-to-Peak Voltage

Figure 2. Differential Peak-to-Peak Voltage

The following tables summarize the DC specifications of the clock input/output levels of the GTM transceivers in Versal Prime devices. Consult the Versal Adaptive SoC GTM Transceivers Architecture Manual (AM017) for further details.

Table 2. GTM Transceiver Clock Input Level Specification
Symbol DC Parameter Min Typ Max Units
VIDIFF Differential peak-to-peak input voltage 250 – 1600 mV
VICM REFCLK common-mode input voltage – VGTM_AVCC – mV
RIN Differential input resistance – 100 – Ω
CEXT Required external AC coupling capacitor – 10 – nF
Table 3. GTM Transceiver Clock Output Level Specification
Symbol Description Conditions Min Typ Max Units
VOL Output Low voltage for P and N RT = 100Ω across P and N signals 100 – 330 mV
VOH Output High voltage for P and N RT = 100Ω across P and N signals 500 – 700 mV
VDDOUT Differential output voltage (P–N), P  =  High (N–P), N = High RT = 100Ω across P and N signals 300 – 430 mV
VCMOUT Common mode voltage RT = 100Ω across P and N signals 300 – 500 mV