lm8322 National Semiconductor Corporation, lm8322 Datasheet - Page 6

• Manufacturer Part Number: lm8322
• Description: Mobile I/o Companion Supporting Key-scan, I/o Expansion, Pwm, And Access.bus Host Interface
• Manufacturer: National Semiconductor Corporation

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7.1 TERMINATION OF UNUSED SIGNALS
C3, C4,
D3, D4
A4, F4
Pin
D6
D1
D2
C1
F3
XTAL_OUT
CONFIG_1
CONFIG_2
KP-Y[11:3]
KP-X[2:0]
KP-X[7:3]
KP-Y[2:0]
XTAL_IN
PWM_0,
PWM_2/
PWM_1
RESET
Signal
IRQ
XTAL_OUT
CONFIG_1
SLOWCLK
Function
GPIO_14
XTAL_IN
RESET
GND
IRQ
V
CC
Connect to V
Connect to V
by the level on this pin. This pin cannot be left unconnected.
This pin is a high-impedance input and must be connected to V
This pin has a weak pullup and can be left open-circuit if it is unused.
These pins are dedicated keypad pins. In the minimum configuration, these pins are keypad inputs
with weak pullups.
These pins are in high-impedance mode after power-on initialization. There are two ways to handle
these pins if unused:
•
•
Care must be taken when connecting to V
WRITE_PORT_SEL or WRITE_PORT_STATE commands could cause excessive current
consumption. A better approach is to leave unused keyboard inputs open-circuit and use the
WRITE_PORT_SEL and WRITE_PORT_STATE commands to configure the pins as inputs with
weak pullups or outputs.
KP-X7 can only be an input. This pin should be programmed as an input with a weak pullup.
These pins are dedicated keypad pins. In the minimum configuration, these pins are keypad outputs
driven low.
These pins are in high-impedance mode after power-on initialization. There are two ways to handle
these pins if unused:
•
•
Care must be taken when connecting to V
WRITE_PORT_SEL or WRITE_PORT_STATE commands could cause excessive current
consumption. A better approach is to leave unused keyboard inputs open-circuit and use the
WRITE_PORT_SEL and WRITE_PORT_STATE commands to configure the pins as inputs with
weak pullups or outputs.
These pins must be connected to V
described in the datasheet.
Connect to V
by the level on this pin. This pin cannot be left unconnected.
This pin must be connected.
Connect to V
Program as inputs with weak pullups or outputs.
Connect to V
Program as inputs with weak pullups or outputs
CC
CC
CC
TABLE 1. Termination of Unused Signals
or GND through a pullup or pulldown resistor because the slave address is selected
or GND through a pullup or pulldown resistor because the slave address is selected
if not driven from an external Supervisory circuit.
CC
CC
Output
or GND.
or GND.
Input
Input
Input
Input
Input
n.a.
n.a.
I/O
I/O
Slave address select input 1
General-purpose I/O port 14
32.768 kHz crystal output
32.768 kHz clock
32.768 kHz crystal input
Interrupt request output
Reset Input
V
Ground
CC
6
CC
or GND if they are not used for any optional function
Termination
CC
CC
or GND. Erroneous parameters sent with the
or GND. Erroneous parameters sent with the
Description
CC
or GND if it is unused.