
Document Number: MC33993
Rev. 4.0, 6/2007
Freescale Semiconductor
Advance Information
* This document contains certain information on a new product.
Specifications and information herein are subject to change without notice.
Freescale Semiconductor, Inc., 2003-2007. All rights reserved.
Multiple Switch Detection
Interface
The 33993 Multiple Switch Detection Interface is designed to detect
the closing and opening of up to 22 switch contacts. The switch status,
either open or closed, is transferred to the microprocessor unit (MCU)
through a serial peripheral interface (SPI). The device also features a
22-to-1 analog multiplexer for reading inputs as analog. The analog
input signal is buffered and provided on the AMUX output pin for the
MCU to read.
The 33993 device has two modes of operation, Sleep and Normal.
The Sleep mode provides low quiescent current and enables the
wake-up features of the device. Normal mode allows programming of
the device and supplies switch contacts with pull-up or pull-down
current as it monitors switch change of state.
The 33993 is packaged in the 32-pin wide-body SOIC, reducing
circuit board area. Low quiescent current makes the 33993 ideal for
automotive and industrial products requiring low sleep state currents.
Features
Designed to Operate 5.5 V
≤
V
PWR
≤
26 V
Switch Input Voltage Range -14 V to V
PWR
, 40 V Max
Interfaces Directly to Microprocessor Using 3.3 V / 5.0 V SPI
Protocol
Selectable Wake-Up on Change of State
Selectable Wetting Current (16 mA or 2.0 mA)
8 Programmable Inputs (Switches to Battery or Ground)
14 Switch-to-Ground Inputs
V
PWR
Standby Current 100
μ
A Typical, V
DD
Standby Current 20
μ
A Typical
Active Interrupt (
INT
) on Change-of-Switch State
Pb-Free Packaging Designated by Suffix Code EW
Figure 1. MC33993 Simplified Application Diagram
MULTIPLE SWITCH
DETECTION INTERFACE
DW SUFFIX
EK SUFFIX (PB-FREE)
98ARH99137A
32-PIN SOICW
33993
ORDERING INFORMATION
Device
Temperature
Range (T
A
)
Package
MC33993DWB/R2
-40°C to 125°C
32 SOICW
MCZ33993EW/R2
V
DD
VDD
VPWR
Power Supply
LVI
Enable
Watchdog
Reset
V
DD
SI
SO
INT
SCLK
CS
AMUX
MOSI
SCLK
CS
MISO
INT
AN0
VBAT
SP0
SP1
SP7
SG1
SG0
SG12
SG13
WAKE
33993
MCU
GND
VBAT
VBAT