MC33972 Datasheet, PDF (1/28 Pages) Motorola, Inc – Multiple Switch Detection Interface with Suppressed Wake-Up

Freescale Semiconductor, Inc.
MOTOROLA
SEMICONDUCTOR TECHNICAL DATA
Document order number: MC33972
Rev 3.0, 12/2004
Advance Information
Multiple Switch Detection Interface
with Suppressed Wake-Up
The 33972 Multiple Switch Detection Interface with Suppressed Wake-Up 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 terminal for the MCU to
read.
The 33972 device has two modes of operation, Normal and Sleep. Normal
mode allows programming of the device and supplies switch contacts with
pullup or pulldown current as it monitors switch change of state. The Sleep
mode provides low quiescent current, which makes the 33972 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 µA Typical, V_DD Standby Current 20 µA
Typical
• Active Interrupt (INT) on Change-of-Switch State
• Pb-Free Packaging Designated by Suffix Code EW
33972
MULTIPLE SWITCH
DETECTION INTERFACE WITH
SUPPRESSED WAKE-UP
DWB SUFFIX
EW (Pb-FREE) SUFFIX
CASE 1324-02
32-TERMINAL SOICW
ORDERING INFORMATION
Device
Temperature
Range (T_A)
Package
MC33972DWB/R2
MC33972EW/R2
-40°C to 125°C
32 SOICW
VBAT
VBAT
VBAT
3397^S2^imS^pi^lm^ifiep^dli^Afi^pe^pd^licA^ap^tip^onlic^Da^iati^go^ran^mDiagram
VDD
33972
SP0
SP1
VPWR
VDD
SP7
SG0
SG1
SG12
WAKE
SI
SCLK
CS
SO
INT
AMUX
Power Supply
LVI
Enable
Watchdog
Reset
MCU
MOSI
SCLK
CS
MISO
INT
AN0
SG13
GND
This document contains information on a new product.
Specifications and information herein are subject to change without notice.
© Motorola, Inc. 2004
For More Information On This Product,
Go to: www.freescale.com