SPC5200CVR400 Freescale Semiconductor, SPC5200CVR400 Datasheet - Page 24

• Manufacturer Part Number: SPC5200CVR400
• Description: IC MPU 32BIT 400MHZ 272-PBGA
• Manufacturer: Freescale Semiconductor

Specifications of SPC5200CVR400

• Processor Type: MPC52xx PowerPC 32-Bit
• Speed: 400MHz
• Voltage: 1.5V
• Mounting Type: Surface Mount
• Package / Case: 272-PBGA
• Features: -

Electrical and Thermal Characteristics
The position of the t
signal indicate if the read data are valid. If the controller is not able to detect a valid MDQS signal on the
sample time (sample position A) then the controller will look for valid MDQS / data on the next edge of
the MEM_CLK signal (sample position B). Depend on the board travel time, different working tap delay
configurations are possible. For a fast connection the data will be sampled with the next edge of
MEM_CLK, this shows
positions are possible.
bigger board delay only sample position B will be possible.
The equation below shows how to calculate the upper and lower limit. The right Tap delay number is
selected, when the possible max and min sample timing is within the memory data valid window.
24
•
•
t
t
t
t
data_sample_max
data_sample_min
data_sample_min
data_sample_min
t
data_valid_max
t
data_valid_min
delay [ns]
4.59
1.55
8.34
Figure 8. Read Data sample window depend on the number of Tap delay
0
data_valid
Figure 8
= min((1.55 + TapNum * 0.095), (1.74 + TapNum * 0.045))
= max((1.55 + TapNum * 0.095), (1.74 + TapNum * 0.045))
Figure
window is depend on the clock / data flight time on the board. The MDQS
8, sample position A. With a longer connection maybe two sample
shows a example with two working sample position (A and B). With a
Working Tap Delay range
for sample position B
MPC5200 Data Sheet, Rev. 4
Memory Data valid window
Working Tap Delay range
for sample position A
selected Tap delay
Possible sample
time over PVT for one
selected Tap delay
Freescale Semiconductor
31
Tap delay number