lm8322 National Semiconductor Corporation, lm8322 Datasheet

lm8322

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

Datasheet

1.LM8322.pdf (42 pages)

Available stocks

Company

Part Number

Manufacturer

Quantity

Price

Company:

Bonase Electronics (HK) Co., Limited

Part Number:

lm8322JGR8/NOPB

Manufacturer:

National Semiconductor

Quantity:

135

Current page: 1 of 42
Download datasheet (859Kb)

LM8322

Mobile I/O Companion Supporting Key-Scan, I/O

Expansion, PWM, and ACCESS.bus Host Interface

1.0 General Description

The LM8322 Mobile I/O Companion is a dedicated device to

unburden a host processor from scanning a matrix-addressed

keypad. In addition, the LM8322 provides general-purpose

I/O expansion, and PWM outputs useful for dynamic LED

brightness modulation.

It communicates with the host through an I

ACCESS.bus interface. An interrupt output is available for

signaling key-press and key-release events. Communication

frequencies up to 400 kHz (Fast-mode) bus speed are sup-

ported. The LM8322 supports a predefined set of commands.

These commands enable a host device to keep control over

all functions.

2.0 Features

Key Features

■

4.0 Block Diagram

Supports keypad matrices of up to 8 × 12 keys plus 8

special-function (SF) keys for a total of 104 keys. SF keys

pull keypad scan inputs directly to ground, rather than

connecting to a keypad scan output.

Supports I

mode up to 400 kHz (Fast-mode).

C-compatible ACCESS.bus interface in slave

300136

C-compatible

■

3.0 Applications

■

Three host-programmable PWM outputs useful for smooth

LED brightness modulation.

Supports general-purpose I/O expansion on pins not

otherwise used for keypad interface.

Key-scan event storage in a FIFO buffer for up to 15

events.

Key events, errors, and dedicated hardware interrupts

request host service by asserting the IRQ output.

The correct reception of a command may be assumed, if

no error is reported from the LM8322 after receiving a

command.

Wake-up from Halt mode on any matrix key-scan event,

any use of the SF keys, or any activity on the ACCESS.bus

interface.

Mobile phones

Personal Digital Assistants (PDAs)

Smart handheld devices

Personal media players

30013620

www.national.com

May 2007

Related parts for lm8322

Related keywords

lm8322 datasheet
lm8322 data sheet
lm8322 pdf datasheet
lm8322 component
lm8322 part
lm8322 distributor
lm8322 RoHS
lm8322 datasheet download