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ICS93718_07 Datasheet, PDF (7/9 Pages) Integrated Device Technology – DDR and SDRAM Buffer
ICS93718
DDR and SDRAM Buffer
Switching Characteristics
DDR_Mode (SEL_DDR = 1), VDD = 2.5±5%
PARAMETER
SYMBOL
CONDITION
MIN TYP MAX UNITS
Operating Frequency
66 133 200 MHz
Input clock duty cycle
dtin
40
50
60
%
Output to Output Skew
Duty cycle
Tskew Output crossover skew DDR[0:11]
DC2
66MHz to 100MHz, w/loads
101MHz to 167MHz, w/loads
48
47
80 100 ps
49
52
%
50
53
%
Rise Time, Fall Time (DDR
Outputs)
trd, tfd
Measured between 20% and 80%
output, w/loads
500
600
700
ps
Switching Characteristics
SD_Mode (SEL_DDR = 0), VDD = 3.3±5%
PARAMETER
SYMBOL
CONDITION
Operating Frequency
Input clock duty cycle
dtin
Output to Output Skew
Duty cycle
Tskew VT = 1.50V
DC2 66MHz to 200MHz
Rise Time, Fall Time
(SDRAM Outputs)
trs, tfs VOL = 0.4V, VOH = 2.4V, w/loads
SDRAM Buffer LH Prop.
Delay1
tPLH Input edge greater than 1V/ns
SDRAM Bufer HL Prop.
Delay1
tPHL Input edge greater than 1V/ns
MIN TYP
66 133
40 50
150
54
0.5 1.5
2
1.9
Notes:
1. Refers to transition on non-inverting output.
2. While the pulse skew is almost constant over frequency, the duty cycle error increases at
higher frequencies. This is due to the formula: duty cycle=t2/t1, were the cycle (t1) decreases
as the frequency goes up.
MAX
200
60
UNITS
MHz
%
ps
%
1.7 ns
2.5 ns
2.5 ns
IDTTM/ICSTM DDR and SDRAM Buffer
ICS93718 REV E 02/11/07