mc33996ek/r2 Freescale Semiconductor, Inc, mc33996ek/r2 Datasheet - Page 11

• Manufacturer Part Number: mc33996ek/r2
• Description: 16-output Switch With Spi Control
• Manufacturer: Freescale Semiconductor, Inc

sent to the 33996 and 24-bit fault word is received from the
33996. The Most Significant Bit (MSB) is sent and received
first.
Table 5. Fault Operation
switch serving as a microcontroller (MCU) bus expander and
buffer with fault management and fault reporting features. In
doing so, the device directly relieves the MCU of the fault
management functions.
system clock serial frequencies up to 6.0 MHz using a Serial
Peripheral Interface (SPI) for control and diagnostic readout.
Analog Integrated Circuit Device Data
Freescale Semiconductor
Overtemperature
Overcurrent
Output “ON’ Open Load Fault
Output “OFF’” Open Load Fault
Device Shutdowns
Overvoltage
Overtemperature
Overcurrent
On each SPI communication, a 24-bit command word is
In operation the 33996 functions as a 16-output serial
The 33996 directly interfaces to an MCU and operates at
Fault reported by Serial Output (SO) pin.
SO pin reports short to battery/supply or overcurrent condition.
Not reported.
SO pin reports output “OFF’” open load condition.
Total device shutdown at V
Upon recovery all outputs assume previous state or OFF based on the Overvoltage bit in the Global
Shutdown/Retry Control Register.
Only the output experiencing an overtemperature fault shuts down. Output may auto-retry or remain
off according to the control bits in the Global Shutdown/Retry Control Register.
Output will remain in current limit 0.9 A to 2.5 A until thermal limit is reached. When thermal limit is
reached, device will enter overtemperature shutdown. Output will operate as programmed in the
Global Shutdown/Retry Control Register. Fault flag in SO Response word will be set.
MCU INTERFACE DESCRIPTION
Serial Output (SO) Pins Reports
OPERATIONAL MODES
PWR
= 27.5 V to 35 V. Resumes normal operation with proper voltage.
Command Register Definition:
SO Definition:
MCU and one 33996.
levels and incorporate positive logic. An input that is
programmed to a logic low state (< 0.8 V) will have the
corresponding output OFF. Conversely, an input
programmed to a logic high state (> 2.2 V) will have the
Microcontroller
Figure 9
All inputs are compatible with 3.3 V / 5.0 V CMOS logic
MC68HCXX
0 = Output Command Off
1 = Output Command On
0 = No fault
1 = Fault
Figure 9. 33996 SPI Interface with Microcontroller
Shift Register
Receive
Parallel
Buffer
Ports
shows the basic SPI configuration between an
MOSI
MISO
SCLK
PWM
RST
FUNCTIONAL DESCRIPTION
CS
SO
SI
OPERATIONAL MODES
24-Bit Shift Register
To Logic
33996
33996
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