Rainbow Electronics AT89C5122 - Manual (Page 59)

59
AT8xC5122/23
4202E–SCR–06/06
Figure 26. Input with Pull-up
Input with Weak Pull-down
Configuration The input with pull-down (input WPD) configuration is shown in Figure 27
Figure 27. Input with Pull-down
Low Speed Output
Configuration The low speed output with low speed t
FALL
and t
RISE
can drive keyboard.
The current limitation of the LED2CTRL block requires a polarisation current of about
250 µA. This block is automatically disabled in power-down mode.
The low speed output configuration (KB_OUT) is shown in Figure 28.
Figure 28. Low-speed Output
LED Source Current The LED configuration is shown in Figure 29.
Input
Pin
Data
Weak
P
Medium
P
Stuck to 0 if Medium
Stuck to 0 if Weak
Input
Pin
Data
Weak
N
1
Pin
P
PWEAKCTRL
Port latch
Data
N
N
NMOS
PCON.1
Weak
LED2CTRL