33884 Datasheet, PDF (1/21 Pages) Freescale Semiconductor, Inc – Switch Monitor Interface

Freescale Semiconductor
Technical Data
Document Number: MC33884
Rev. 4.0, 11/2006
Switch Monitor Interface
The 33884 Switch Monitor Interface is a monolithic silicon integrated
circuit (IC) to perform switch monitoring functions. The device provides
efficient interface between electrical switches and low voltage
microprocessors. The 33884 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.
33884
SWITCH MONITOR INTERFACE
There are four modes of operation: Sleep, Normal, Polling, and
Polling + INT Timer.
The Polling and Timer modes are similar, except the Timer mode
has the addition of an interrupt that is sent to the microprocessor if a
switch is sensed closed, or upon the internal interrupt timer times out.
An interrupt is ultimately sent to the microprocessor. All modes of
operation are easily programmed via the Serial Peripheral Interface
(SPI) control.
Features
DW SUFFIX
EG (PB-FREE) SUFFIX
98ASB42344B
24-PIN SOICW
• Full Operation with 7.0 V < V_PWR < 26 V, Limited Operation with
5.5 V < V_PWR < 7.0 V
• Input Voltage Range: -14 V to 40 V
• Interface Directly to Microprocessors Using SPI Protocol
ORDERING INFORMATION
Device
Temperature
Range (T_A)
Package
• Wake Up on Change of Monitored Switch Status
• Programmable Wetting Current
• Four Switch-to-Ground Switches
MC33884DW/R2
-40°C to 105°C
MCZ33884EG/R2
24 SOICW
• Six (Fixed Function) Inputs Monitoring Six Switch-to-Ground
Switches
• Two (Fixed Function) Inputs Monitoring Two Switch-to-Battery Switches
• Quiescent Current in Sleep Mode < 10 µA
• Reset Input Defaults the Device to Sleep Mode
• Pb-Free Packaging Designated by Suffix Code EG
VPWR
2 VPWR
Sense Inputs
4 GND / VPWR
Sense Inputs
6 GND
Sense Inputs
33884
SB1 ^VPWR
SB2
VDD
SP1
CS
SI
SP2
SO
SP3 SCLK
SP4
INT
SG1 ^RESET
SG2
SG3
GND
VBG
SG4 ^SYNC
SG5 ^MASL
SG6
VDD
MCU
VDD
CS
MOSI
MISO
CLK
INT
RESET
GND
Figure 1. 33884 Simplified Application Diagram
Freescale Semiconductor, Inc. reserves the right to change the detail specifications, as
may be required, to permit improvements in the design of its products.
© Freescale Semiconductor, Inc., 2006. All rights reserved.