11
Differential Signal AC Output Parameters Tests
178
DDR2(+LP) Compliance Testing Methods of Implementation
SRQdiffF (40ohm) - Test Method of Implementation
SRQdiffF (40ohm) - Differential Output Falling Slew Rate (40ohms).
The purpose of this test is to verify that the differential falling slew rate value of the test signal must
be within the conformance limit of the SRQ
diff
value as specified in the JEDEC specification.
Signals of Interest
Mode Supported: LPDDR2 only
Signal cycle of interest: READ
Signal(s) of Interest:
• Data Strobe Signal (supported by Data Signal)
Signals required to perform the test on the oscilloscope:
• Pin Under Test, PUT - Data Strobe Signals
• Supporting Pin - Data Signals
Test Definition Notes from the Specification
Test References
See Table 87 - Output Slew Rate (differential) in the
JESD209-2B
.
PASS Condition
The worst measured SRQdiffF shall be within the specification limit.
Measurement Algorithm
1 Acquire and split read and write bursts of the acquired signal.
2 Take the first valid READ burst found.
3 Find all valid Strobe falling edges in this burst. A valid Strobe falling edge starts at the V
OHdiff(AC)
crossing and ends at the following V
OLdiff(AC)
crossing.
4 For all valid Strobe falling edges, find the transition time, TR, which is the time that starts at the
V
OHdiff(AC)
crossing and ends at the following V
OLdiff(AC)
crossing. Then calculate
SRQdiffF = [V
OHdiff(AC)
- V
OLdiff(AC)
]/TR.
5 Determine the worst result from the set of SRQdiffF measured.
Table 110
LPDDR2 Output Slew Rate (differential)
Parameter
Symbol
LPDDR2-1066 to LPDDR2-200
Units
Min
Max
Differential Output Slew Rate (RON = /- 30%)
SRQ
diff
3.0
7.0
V/ns
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 ...