MC33884 Datasheet, PDF (1/20 Pages) Motorola, Inc – Switch Monitor Interface

MOTOROLA
SEMICONDUCTOR TECHNICAL DATA
Advance Information
Switch Monitor Interface
The MC33884 Switch Monitor Interface is a monolithic silicon
integrated circuit (IC) that performs switch monitoring functions.
The device provides efficient interface between electrical switches
and low voltage microprocessors. The MC33884 supplies switch
contact pull–up and pull–down current while monitoring the input
voltage level. All inputs are protected for transients when
implemented with an appropriate static discharge capacitor used
on the inputs.
There are four modes of operation – Sleep, Normal, Polling, and
Polling + INT Timer. Sleep mode reduces the current drain to a
quiescent current level of 10 mA and disables the IC. Normal mode
interrupts the microprocessor whenever any external switch
changes it’s OPEN or CLOSED state. Polling mode reads a switch
status periodically and interrupts the microprocessor only when an
external switch is sensed as being CLOSED. The Polling + INT
Timer mode is similar to the Polling mode, with the addition of an
interrupt being sent to the microprocessor if a switch is sensed
CLOSED or upon the internal interrupt timer ”timing out”. An
interrupt is always ultimately sent to the microprocessor in this
mode. All modes of operation are easily programmed via the Serial
Peripheral Interface (SPI) control.
The MC33884 has the following features:
• Full Operation with 7.0 V ≤ VPWR ≤ 26 V,
Limited Operation with 5.5 V ≤ VPWR ≤ 7.0 V
• Input Voltage Range: –14 V to 40 V
• Interfaces Directly to Microprocessors Using SPI Protocol
• 24–Lead Wide Body SOIC Package
• Wake–up on Change of Monitored Switch Status
• Programmable Wetting Current
• 4 Programmable Inputs to Monitor 4 Switch–to–Battery or
4 Switch–to–Ground Switches
• 6 (fixed function) Inputs to Monitor 6 Switch–to–Ground Switches
• 2 (fixed function) Inputs to Monitor 2 Switch–to–Battery Switches
• Standby Current During Normal Mode = 100 mA
• Quiescent Current in Sleep Mode < 10 mA
• Reset (RST) Input Defaults the Device to Sleep Mode
• Active Interrupt (INT) on Change of Switch State in Normal Mode
• 4 Modes of Operation
(Sleep, Normal, Polling, Polling + INT Timer)
• Designed to Operate –40°C ≤ TA ≤ 105°C
Order this document
by MC33884/D
MC33884
SCALE 1:1
DW Suffix
24 Lead SOIC
CASE 751E
PIN CONNECTIONS
VDD
1
SO
2
SI
3
SP1
4
SG1
5
SG2
6
SG3
7
SB1
8
SP2
9
MASL
10
VPWR
11
GND
12
24
SCLK
23
CSB
22
VBG
21
SP4
20
SG6
19
SG5
18
SG4
17
SB2
16
SP3
15
INTB
14
SYNC
13
RSTB
ORDERING INFORMATION
Device
MC33884DW
MC33884DWR2
Operating
Temperature Package
Range
TA = – 40 to
105°C
SO–24
TA = – 40 to
105°C
SO–24
This document contains information on a new product. Specifications and information herein are subject to change without notice.
REV 2
09/01
© Motorola, Inc. 2001
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