AN2536 Freescale Semiconductor / Motorola, AN2536 Datasheet - Page 15

• Manufacturer Part Number: AN2536
• Description: MC9328MX1 and MC9328MXL High Speed Layout Design Guidelines
• Manufacturer: Freescale Semiconductor / Motorola

The address line A2 is connected to two SDRAMs and two SyncFlashs. The worst waveform has been
captured on the memory device pin A2 (Figure 22). This is referenced to the SDLCK signal at the SDCLK
pin of same device.
Considering the setup time requirement, the connection length between the memory and the
MC9328MX1/MXL is suggested to be within 4.5cm (indicated by the red line in Figure 23) and it is
recommended the total metal delay should be smaller than 940ps, trace inductance within 40nH and trace
MOTOROLA
NET = A2 (The whole trace incl. the route to Socket)
-------
-------
NET = SDCLK (The whole trace incl. the route to Socket)
Figure 22. Board Vendor’s Simulated Trace Data and Waveforms Captured from the ADS v1.1
COUNTS ------------------------------------------------------------
INTERCONNECT STATISTICS ------------------------------------
COUNTS ------------------------------------------------------------
INTERCONNECT STATISTICS ------------------------------------
segments ........... 34
IC drivers ......... 0
IC receivers ....... 7
resistors .......... 0
capacitors ......... 0
total metal delay ............ 707.073 ps
minimum metal Z0 ............. 41.7 ohms
maximum metal Z0 ............. 59.2 ohms
total metal capacitance ...... 15.4 pF
total metal inductance ....... 33.3 nH
total metal resistance ....... 297.7 milliohms
total metal length ........... 010.405 cm
average metal Z0 ............. 46.5 ohms
segments ........... 32
IC drivers ......... 0
IC receivers ....... 7
resistors .......... 0
capacitors ......... 0
total metal delay ............ 904.342 ps
minimum metal Z0 ............. 28.8 ohms
maximum metal Z0 ............. 45.1 ohms
total metal capacitance ...... 23.5 pF
total metal inductance ....... 34.9 nH
total metal resistance ....... 212.1 milliohms
total metal length ........... 014.292 cm
average metal Z0 ............. 38.5 ohms
Trace length from
MC9328MX1/MXL to
Memories
Total trace length from
MC9328MX1/MXL to
SODIMM
Figure 23. Trace Layout Illustration for the ADS v1.1 Memory System
Freescale Semiconductor, Inc.
For More Information On This Product,
MC9328MX1/MXL Application Note
To Memories
Go to: www.freescale.com
U25: Trace Length = 1.8359cm, Setup Time = 3.28ns
U26: Trace Length = 4.5493cm, Setup Time = 3.24ns
U27: Trace Length = 4.13765cm, Setup Time = 3.40ns
U28: Trace Length = 6.65475cm, Setup Time = 2.32ns
SDRAM
set up time
SyncFlash
set up time
MC9328MX1/MXL Case Study
To SODIMM
15