MC33975EK Freescale Semiconductor, MC33975EK Datasheet - Page 14

• Manufacturer Part Number: MC33975EK
• Description: IC SWITCH DETECT MULT 32-SOICW
• Manufacturer: Freescale Semiconductor

Specifications of MC33975EK

• Applications: *
• Interface: *
• Package / Case: 32-SOIC (7.5mm Width) Exposed Pad, 32-eSOIC, 32-HSOIC
• Mounting Type: Surface Mount
• Voltage - Supply: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

ANALOG CONTROL AND PROTECTION
CIRCUITRY:
the VPWR terminal. Characteristics are provided from 8.0V to
28V for the device. Switch contact currents and the internal
logic supply are generated from the VPWR terminal. The
VDD supply terminal is used to set the SPI communication
voltage levels, current source for the SO driver, and pull-up
current on INT and CS.
required voltages to the internal monitor circuitry. The
temperature monitor is active in the Normal Mode.
MCU INTERFACE AND CONTROL:
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).
14
33975
FUNCTIONAL DESCRIPTIONS
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
The 33975 is designed to operate from 5.5V to 38/40V on
The on-chip voltage regulator and bandgap supplies the
The 33975 Multiple Switch Detection Interface with
MC33975 - Functional Block Diagram
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
Analo Control
Figure 7. Functional Internal Block Description
reading inputs as analog. The 33975 device has two modes
of operation, Normal and Sleep.
SWITCH PROGRAMMABLE INPUTS:
selectively detect switch closures to Ground or Battery. The
33975 device has 8 switch inputs capable of being
programmed to read switch-to-ground or switch-to-battery
contacts. The input is compared with a 4.0V reference. When
programmed to be switch-to-battery, voltages greater than
4.0V are considered closed. Voltages less than 4.0V are
considered open. The opposite holds true when inputs are
programmed as switch-to-ground.
SWITCH–TO-GROUND INPUTS:
detect switch closures to ground only. The input is compared
with a 4.0V reference. Voltages greater than 4.0V are
considered open. Voltages less than 4.0V are considered
closed. Note: Each of these inputs may be used to supply
current to sensors external to a module.
The device also features a 22-to-1 analog multiplexer for
Programmable switch detection inputs. These 8 inputs can
Switch detection interface inputs. These 14 inputs can
Analog Integrated Circuit Device Data
Freescale Semiconductor