Recommended Connection Of Unused Pins - NEC µPD72257 Preliminary User's Manual

Pin Functions

2.5 Recommended Connection of unused Pins

"Signal"
"Unused"
Internal pull-up
resistors
Caution
Table 2-11
Pin Option 1
Signal Unused
1 VO0G4 open
2 VO0G5 open
3 VO0B0 open
4 VO0B1 open
5 DVDD33 n/a
6 DGND33 n/a
7 VO0B2 open
8 VO0B3 open
9 VO0B4 open
10 VO0B5 open
11 VO0HSYNC open
12 VO0VSYNC open
In this section recommendations are given how to treat pins, which are not used
in an application.
The tables give recommended connnections of unused pin for all Ravin-M pinout
options as well as for Ravin-L in the last table.
The "Signal" column lists the signal name of the pin's function with the respective
pinout option.
"Unused" signals must not be used with the pinout option do not require an
external connection.
The "Unused" column specifies how to connect a pin, if it is not used by the
application:
• open: leave the pin open.
• iPU: an internal pull-up resistor is enabled for the concerned pin
• a
iPU : If the internal RAM of Ravin-L is enabled
(SYSBOOTMODE.BOOTMODE9 = 1), internal pull-up resistors of the
external memory data bus MD[15:0] pins are enabled.
• n/a: not applicable, these pins must be connected in any case
Depending on the pinout option, several pins are internally connected to pull-up
resistors. Thus these signal can be in principle left open, if not used, as they are
clamped to high level internally.
According to the chosen pinout option pull-up resistors are activated in order to
prevent malfunction of the graphics controller due to unspecified pin levels.
Since the pull-up resistors can be disabled respectively enabled in groups by
modifying SYSPINMUX.BUFPUEN[7:0], take care for external pin level fixation,
if the internal pull-up resistors are disabled.
Connection of unused pin for Ravin-M options 1, 2, 3, 6a
Option 2
Signal Unused
VO0G4 open
VO0G5 open
VO0B0 open
VO0B1 open
DVDD33 n/a
DGND33 n/a
VO0B2 open
VO0B3 open
VO0B4 open
VO0B5 open
VO0HSYNC open
VO0VSYNC open
Preliminary User's Manual S19203EE1V3UM00
Ravin-M
Option 3
Signal Unused
VO0G4 open
VO0G5 open
VO0B0 open
VO0B1 open
DVDD33 n/a
DGND33 n/a
VO0B2 open
VO0B3 open
VO0B4 open
VO0B5 open
VO0HSYNC open
VO0VSYNC open
Chapter 2
Option 6a
Signal Unused
VO0G4 open
VO0G5 open
VO0B0 open
VO0B1 open
DVDD33 n/a
DGND33 n/a
VO0B2 open
VO0B3 open
VO0B4 open
VO0B5 open
VO0HSYNC open
VO0VSYNC open
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