AN2434 Freescale Semiconductor / Motorola, AN2434 Datasheet - Page 13

• Manufacturer Part Number: AN2434
• Description: Input/Output (I/O) Pin Drivers
• Manufacturer: Freescale Semiconductor / Motorola

Source and Sink for Reduced Drive
HCS12 I/O pins include a reduced current mode. This mode is provided to reduce EMI emissions in cases
where the load being driven by the I/O pins is light and full drive strength is not needed. The reduced drive
strength is approximately one third of full drive strength. Reduced drive strength is configurable on the
PIM-based I/O ports through individual reduced drive registers for each port (RDRx). (This would include
all I/O ports other than ports A, B, E, and K.)
Figure 11
pins.
Freescale Semiconductor
and
Figure 12
3.5
2.5
1.5
0.5
SPECIFIED I
3
2
1
0
Figure 11. V
0
show V
OH
OH
and V
OH
MC9S12DP256, 25°C, V
2
Input/Output (I/O) Pin Drivers, Rev. 0
versus Source Current — Reduced Drive
OL
versus current for the reduced drive configuration of the GPIO
4
I
OH
(mA)
DD
6
= 5 V
Source and Sink for Reduced Drive
8
0.8 V = V
DD
– V
OH
10
13