DDR2(+LP) Compliance Testing Methods of Implementation
113
Single-Ended Signals VIH/VIL (Data, Mask) Tests
6
Measurement Algorithm
1 Acquire and split read and write bursts 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 is for
differential DQS and V
REF
is for single ended DQS.)
5 Set up histogram function settings.
• 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.
• Ay: Top of the displaying window just to make sure it covers the maximum level of the
respective signal.
• By: Y- position at the V
REF
voltage level.
6 Take the 'Min' value of the histogram as the test result for V
IHDQ(DC)
.
7 Collect all V
IHDQ(DC)
.
8 Determine the worst result from the set of V
IHDQ(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 ...