MC33993DWB Freescale Semiconductor, MC33993DWB Datasheet - Page 11

• Manufacturer Part Number: MC33993DWB
• Description: IC SWITCH I/O INTERFACE 32-SOIC
• Manufacturer: Freescale Semiconductor

Specifications of MC33993DWB

• Applications: *
• Interface: *
• Voltage - Supply: *
• Package / Case: 32-SOIC (7.5mm Width)
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

MCU INTERFACE DESCRIPTION
microcontroller unit (MCU). SPI serial clock frequencies up to
6.0 MHz may be used for programming and reading switch
input status (production tested at 4.16 MHz).
illustrates the configuration between an MCU and one 33993.
device through the SI input pin. As data is being clocked into
the SI pin, status information is being clocked out of the
device by the SO output pin. The response to a SPI
command will always return the switch status, interrupt flag,
and thermal flag. Input switch states are latched into the SO
register on the falling edge of the chip select (CS) pin.
Twenty-four bits are required to complete a transfer of
information between the 33993 and the MCU.
system. Multiple ICs may be SPI-configured in parallel or
serial.
the serial configuration, 48-clock cycles are required to
transfer data in / out of the ICs.
Analog Integrated Circuit Device Data
Freescale Semiconductor
The 33993 device directly interfaces to a 3.3 V or 5.0 V
Serial peripheral interface (SPI) data is sent to the 33993
Two or more 33993 devices may be used in a module
Microcontroller
MC68HCXX
Shift Register
Figures 8
Figure 7. SPI Interface with Microprocessor
Receive
Parallel
Buffer
Ports
and
9
MOSI
MISO
SCLK
INT
show the configurations. When using
INT
SO
CS
SI
FUNCTIONAL DEVICE OPERATION
24-Bit Shift Register
Figure 7
33993
To Logic
Microcontroller
Figure 8. SPI Parallel Interface with Microprocessor
Microcontroller
MC68HCXX
Figure 9. SPI Serial Interface with Microprocessor
Shift Register
MC68HCXX
Shift Register
Parallel
Parallel
Ports
Ports
INT
INT
SCLK
MOSI
MISO
SCLK
MOSI
MISO
FUNCTIONAL DEVICE OPERATION
FUNCTIONAL PIN DESCRIPTION
SI
SO
SCLK
CS
INT
SI
SO
SCLK
CS
INT
SI
SO
SCLK
CS
INT
SI
SO
SCLK
CS
INT
33993
33993
33993
33993
33993
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