DDR2(+LP) Compliance Testing Methods of Implementation
65
Single-Ended Signals AC Input Parameters Tests
4
PASS Condition
The minimum value of test signal from tDS before DQS midpoint to tDH after DQS midpoint for the
high level voltage shall be greater than or equal to the minimum V
IH(DC)
value.
Measurement Algorithm
1 Acquire and split read and write burst of the acquired signal.
2 Take the first valid WRITE burst found.
3 Find all valid rising DQ crossings that cross V
IH(AC)
in the burst.
4 For all DQ crossings found, locate all the following DQS crossings that cross midpoint. (0V for
differential DQS and V
REF
for single ended DQS)
5 Setup the histogram function settings where the X region is:
• Ax: X-time position where tDS (DM and DQ input setup time in JEDEC specification) before
DQS crossing midpoint.
• Bx: X-time position where tDH (DM and DQ input hold time in JEDEC specification) after DQS
crossing midpoint.
• By: Y- position at VREF voltage level.
• Ay: Top of the displaying window just to make sure it covers the maximum level of the
respective signal.
6 Take histogram 'Min' value as the test result for V
IH(DC)
.
7 Collect all V
IH(DC)
.
8 Determine the worst result from the set of V
IH(DC)
measured.
Summary of Contents for D9020DDRC
Page 1: ...Keysight D9020DDRC DDR2 LP Compliance Test Application Methods of Implementation ...
Page 10: ...10 DDR2 LP Compliance Testing Methods of Implementation ...
Page 46: ...2 Preparing to Take Measurements 30 DDR2 LP Compliance Testing Methods of Implementation ...
Page 70: ...3 Measurement Clock Tests 54 DDR2 LP Compliance Testing Methods of Implementation ...
Page 224: ...14 Clock Timing CT Tests 208 DDR2 LP Compliance Testing Methods of Implementation ...
Page 270: ...15 Data Strobe Timing DST Tests 254 DDR2 LP Compliance Testing Methods of Implementation ...