DDR2(+LP) Compliance Testing Methods of Implementation
115
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 falling DQ crossings that cross V
IL(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 Calculate the time where the test result is taken. Calculation is expressed as:
T
TESTRESULT
= T
DQS MIDPOINT
– tDS.
(tDS – DM and DQ input setup time in JEDEC specification which is due to speed grade).
6 Take voltage level of DQ signal at T
TESTRESULT
as the test result for V
ILDQ(AC)
.
7 Collect all V
ILDQ(AC)
.
8 Determine the worst result from the set of V
ILDQ(AC)
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 ...