Freescale Semiconductor
Technical Data
Document Number: MC33298
Rev. 6.0, 4/2008
Eight Output Switch with Serial
Peripheral Interface I/O
The 33298 is a smart eight output low side power switch. It is a
versatile device incorporating an 8-bit serial-in shift register to control
an 8-bit parallel output latch providing control of eight independent
"ON/OFF" output switches. Applications include the control of
solenoids, relays, lamps, small DC motors, and other moderate current
loads (1.0 – 3.0A).
The 33298 interfaces directly with a microcontroller to control
various inductive or incandescent loads. Input control is fast. Data
rates are guaranteed to 2.0 MHz but the device is capable of rates to
8.5 MHz @ 25°C.
Each output uses high efficiency MOSFET power transistors
configured with open drains. Each low "ON" resistance output (0.4Ω
R
DS(ON)
@ 25°C) is capable of sinking up to 3.0A of transient current.
On a continuous basis, each output can simultaneously (with all
outputs "ON") handle 0.5A of current when the device is soldered onto
a typical PC board. Higher output currents are dependent on the
number of outputs simultaneously "ON". The circuit's innovative
monitoring and protection features include very low standby current.
Features
33298
LOW SIDE SWITCH
DW SUFFIX
EG SUFFIX (PB-FREE)
98ASB42344B
24 SOICW
ORDERING INFORMATION
Device
MC33298DW/R2
-40°C to 125°C
24 SOIC
Temperature
Range (T
A
)
Package
• Designed to operate over wide supply voltages of 5.5 to 26.5V
MCZ33298EG/R2
• Interfaces to microprocessor using 8-bit SPI I/O protocol up to
3.0MHz
• 1.0A peak current outputs with maximum R
DS(ON)
of 1.8Ω at T
J
- 150°C
• Outputs current limited to accommodate in-rush currents associated with switching incandescent loads
• Output voltages clamped to 65V during inductive switching
• Maximum sleep current (I
PWR
) of 25µA
• Maximum of 4.0mA I
DD
during operation
• Pb-free packaging designated by suffix code EG
VDD
V PWR
33298
VPWR
SFPD
VDD
CS
MCU
SCLK
SI
SO
RESET
OP 0
OP 1
OP 2
OP 3
OP 4
OP 5
OP 6
OP 7
GND
Figure 1. 33298 Simplified Application Diagram
Freescale Semiconductor, Inc. reserves the right to change the detail specifications, as
may be required, to permit improvements in the design of its products.
© Freescale Semiconductor, Inc., 2007-2008. All rights reserved.
FREESCALE [ FREESCALE SEMICONDUCTOR, INC ]
