MC33975ATEK Datasheet, PDF (1/32 Pages) Freescale Semiconductor, Inc – Multiple Switch Detection Interface with Suppressed Wake-up and 32 mA Wetting Current

Freescale Semiconductor
Advance Information
Document Number: MC33975
Rev 10.0, 8/2011
Multiple Switch Detection
Interface with Suppressed
Wake-up and 32 mA Wetting
Current
The 33975 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 33975 device has two modes of operation, Normal and Sleep.
Normal mode allows programming of the device and supplies switch
contacts with pull-up or pull-down current as it monitors the switch
change of state. The Sleep mode provides low quiescent current,
which makes the 33975 ideal for automotive and industrial products
requiring low sleep state currents.
Improvements are a programmable interrupt timer for Sleep mode
that can be disabled, switch detection currents of 32 mA and 4.0 mA
for switch-to-ground inputs, and an interrupt bit that can be reset.
Features
• Designed to operate from 5.5 V ≤ V_PWR ≤ 28 V
• Switch input voltage: (33975: -14 to 38 V) (33975A: -14 to 40 V)
• Interfaces to microprocessor using 3.3 V/5.0 V SPI protocol
• Selectable wake-up on change of state
• 14 switch-to-ground inputs
• 8 programmable inputs (switches to battery or ground)
• Selectable wetting current (32 mA or 4.0 mA for switch-to-ground
inputs)
• Sleep State current V_PWR 100 μA, V_DD 20 μA
• Pb-free packaging designated by suffix code EK
33975
33975A
MULTIPLE SWITCH
DETECTION INTERFACE WITH
SUPPRESSED WAKE-UP
EK SUFFIX (PB-FREE)
98ASA10556D
32-PIN SOICW EP
ORDERING INFORMATION
Device
Temperature
Range (T_A)
MC33975TEK/R2
-40 °C to 125 °C
MC33975ATEK/R2
Package
32 SOICW-EP
VDD
V_BAT
V_BAT
33975
SP0
VPWR
SP1
VDD
SP7
WAKE
SG0
SG1
SG12
SG13
SI
SCLK
CS
SO
INT
AMUX
GND
V_BAT
VDD
POWER SUPPLY
LVI
ENABLE
MCU
MOSI
SCLK
CS
MISO
INT
AN0
WATCHDOG
RESET
Figure 1. 33975 Simplified Application Diagram
* This document contains certain information on a new product.
Specifications and information herein are subject to change without notice.
© Freescale Semiconductor, Inc., 2005 - 2011. All rights reserved.