AM3505 I/O Drive Strength

Russell Cumber

What is the drive strength/ output impedance of the various pin types (SDRC, GMPC, GPIO)?

Does the SDRC correlate to the SSTL18-II standard with 18ohms output impedance in normal mode and 40 ohms in low power?

GPMC and GPIO are ...?

0 Jeff Culverhouse over 14 years ago

Hello,

the drive strengths are listed in the Ball Characteristics table in the data manual (table 2-1).

SDRC data lines = 4pF
SDRC Address and clk lines = 8pF
GPMC = 30pF
GPIO = 30pF

0 Russell Cumber over 14 years ago in reply to Jeff Culverhouse

I was actually looking for the current capabilities of the various pins (8mA, 12mA, etc).

0 Jeff Culverhouse over 14 years ago in reply to Russell Cumber

Hello Russell,

For the SDRC pins we are compliant to the JESD79-2A Standard.

0 Brad Griffis over 14 years ago

Russell Cumber said:

What is the drive strength/ output impedance of the various pin types (SDRC, GMPC, GPIO)?

Russell,

There are only 2 types of I/Os:

1.8V-only LVCMOS pins, which is the case for the SDRC. These pins conform to the JESD79-2A Standard as Jeff mentioned.
Dual-voltage LVCMOS pins. This encompasses the GPMC and all the other I/Os that are part of the VDDSHV power domain. The specifications for these I/O are given in the DC Electrical Characteristics of the data sheet. The I_OH/I_OL is +/- 2mA in that table.

Best regards,
Brad

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