MC33298DWR2 Freescale Semiconductor, MC33298DWR2 Datasheet - Page 13

• Manufacturer Part Number: MC33298DWR2
• Description: IC OCTAL SERIAL SWITCH 24-SOIC
• Manufacturer: Freescale Semiconductor
• Type: Low Sider

Specifications of MC33298DWR2

• Input Type: SPI
• Number Of Outputs: 8
• On-state Resistance: 350 mOhm
• Current - Output / Channel: 1A
• Current - Peak Output: 4A
• Voltage - Supply: 9 V ~ 26.5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 24-SOIC (7.5mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: MC33298DWTR

developed for automotive applications. It is an eight output
low side power switch having 8-bit serial control. The 33298
incorporates SMARTMOS™ technology having effective 1.5µ
CMOS logic, bipolar/MOS analog circuitry, and independent
state of the art double diffused MOS (DMOS) power output
transistors. Many benefits are realized as a direct result of
using this mixed technology. A simplified block diagram
delineates 33298 in
current for their operation, structured MOS devices, since
they are voltage controlled, require only transient gate
charging current affording a significant decrease in power
consumption. The CMOS capability of the SMARTMOS
process allows significant amounts of logic to be
economically incorporated into the monolithic design.
Additionally, the bipolar/MOS analog circuits embedded
within the updrain power DMOS output transistors monitor
and provide fast, independent protection control functions for
each individual output. All outputs have internal 65V at 0.5A
independent output voltage clamps to provide fast inductive
turn-off and transient protection.
output transistors exhibiting very low room temperature
drain-to-source ON resistance values (R
V
currents of less than 2.0mA (1.0mA typical) with any
combination of outputs ON are the result of using this mixed
technology and would not be possible with bipolar structures.
To accomplish a comparable functional feature set using a
bipolar structure approach, would result in a device requiring
hundreds of milliamperes of internal bias and control current.
This would represent a very large amount of power to be
consumed by the device itself and not available for load use.
serial switch serving as a microcontroller (MCU) bus
expander and buffer, with fault management and fault
reporting features.
fault management functions.
Analog Integrated Circuit Device Data
Freescale Semiconductor
PWR
The 33298 was conceived, specified, designed, and
Where bipolar devices require considerable control
The 33298 uses high efficiency updrain power DMOS
During operation, the 33298 functions as an eight output
In doing so, the device directly relieves the MCU of the
) and dense CMOS control logic. Operational bias
Figure
1.
DS(on)
FUNCTIONAL DESCRIPTION
≤ 1.0Ω at 13V
INTRODUCTION
management functions. The 33298 directly interfaces to an
MCU, operating at system clock serial frequencies in excess
of 3.0MHz. It uses a Synchronous Peripheral Interface (SPI)
for control and diagnostic readout.
basic SPI configuration between an MCU and one 33298.
applications in the computer, telecommunications, and
industrial fields. It is parametrically specified over an input
battery /supply range of 9.0 to 16V but is designed to operate
over a considerably wider range of 5.5 to 26.5V. The design
incorporates the use of Logic Level MOSFETs as output
devices. These MOSFETs are sufficiently turned ON with a
gate voltage of less than 5.0V thus eliminating the need for
an internal charge pump. Each output is identically sized and
independent in operation. The efficiency of each output
transistor, at room temperature provides as little as 9.0V
supply (V
incorporating negative or inverted logic. Whenever an input is
programmed to a logic low state (<1.0V) the corresponding
low side switched output being controlled will be active low
and turned ON. Conversely, whenever an input is
programmed to a logic high state (>3.0V), the output being
controlled will be high and turned OFF.
The 33298 directly relieves the MCU of the fault
The circuit can also be used in a variety of other
All inputs are compatible with 5.0V CMOS logic levels,
Figure 13. SPI Interface with Microcontroller
Microcontroller
MC68HCXX
Shift Register
PWR
Receive
Parallel
Buffer
Ports
), the maximum R
MOSI
MISO
SCLK
RST
CS
DS(on)
FUNCTIONAL DESCRIPTION
Figure 13
of an output
SO
SI
INTRODUCTION
Shift Register
illustrates the
33298
Logic
To
33298
13