R31DS0210EU0106 Rev.1.06

Page 30

May 11, 2026

RC193xx Datasheet

3. Test Loads

Figure 10. AC/DC Test Load for Differential Outputs (Standard PCIe Source-Terminated)

Figure 11. AC/DC Test Load for Differential Outputs (Double-Terminated or Receiver-Terminated)

Table 28. Parameters for AC/DC Test Load (Standard PCIe Source-Terminated)

Clock Source

L (cm)

CL (pF)

ZOUTSEL_tri pin

Zo (ohms)

Rs (ohms)

SMA100B

25.4

2

0 (85 ohms)

85

Internal

1 (100 ohms)

100

Internal

Mid (34 ohms)

85

External 25.5

100

External 33.3

Table 29. Parameters for AC/DC Test Load (Double-Terminated)

Clock Source

L (cm)

CL (pF)

ZOUTSEL_tri pin

Zo (ohms)

Rs (ohms)

SMA100B

25.4

2

0 (85 ohms)

85

Internal

1 (100 ohms)

100

Internal

Mid (34 ohms)

85

None[1]

1. This setting is designed to provide additional amplitude for receiver-terminated loads by turning off the source termination in the output driver.

There is no reflection with receiver terminated loads since the receiver termination absorbs the incident waveform.

100

DUT Board

CKIN+

CK+

DUT Chip

CKIN-

CK-

Zo (differential)

Rs

Rs

CL

CL

CK+

Clock Source

CK-

DSO

Probes

SMA

DUT Board

CKIN+

CK+

DUT Chip

CKIN-

CK-

Zo (differential)

Rs

Rs

CL

CL

CK+

Clock Source

CK-

SMA

SMA

DSO

50

50