MC33812FS, Multifunction Ignition and Injector Driver

Analog, Mixed Signal and Power Management
MC33812
Multifunctional Ignition and Injector Driver
Overview
With increasing gas prices and
worldwide emissions regulations, small
engine applications face increasing
pressure to be green.
In the automotive industry, Freescale
has been on the forefront of the change
from mechanical to electronic engine
control. We are now leading the way to
make this change in the small engine
industry as well.
The 33812 is an engine control
analog power IC intended for motorcycle
and other single/dual cylinder small
engine control applications. The IC
consists of three integrated low side
drivers, one pre-driver, 5.0 V voltage
pre-regulator, an MCU watchdog circuit,
an ISO 9141 K-Line interface and a
parallel interface for MCU
communication. The three low side
drivers are provided for driving a fuel
injector, a lamp or LED, and a relay or
another injector or fuel pump. The predriver is intended to drive either an
Insulated Gate Bipolar Transistor (IGBT)
or a bipolar Darlington transistor to
control an ignition coil.
MC33812 Simplified Application Drawing
Applications
•
•
•
•
•
Small Engine Control
Lawn Mowers
Scooters
Small Motorcycles
Lawn Trimmers
•
•
•
•
Snow Blowers
Chain Saws
Gas-driven Electrical Generators
Outboard Motors
Features
• Designed to operate over the range of
~4.7 V ≤ VPWR ≤ 36 V
• Fuel injector driver - current limit - 4.0 A
typical
• Ignition pre-driver can drive IGBT or
Darlington bipolar junction transistors
• Ignition pre-driver has independent high
and low side outputs
• Relay/injector/fuel pump driver - current
limit - 4.0 A typical
• Lamp driver- current limit - 1.5 A typical
• All external outputs protected against
short to battery and over-current
• All drivers protected against overtemperature
• Interfaces directly to MCU using 5.0 V
parallel interface
• VCC voltage pre-regulator provides
+5.0 V power for the MCU
• MCU Power On RESET generator
• MCU watchdog timer circuit with parallel
refresh/time setting line
• Independent fault annunciation outputs
for ignition, injection and relay
• ISO-9141 K-Line transceiver for
communicating diagnostic messages
• Pb-free packaging designated by suffix
code EK
Benefits
• Increased fuel efficiency when
converting from a mechanical system to
an electrical system
• Improved emissions using electrical
system of this IC compared to a
mechanical system
• Easiest way to interface a micro
controller to DC loads
• Simplified system design
• Reduced board space
• Reduce number of components
• Enhanced reliability
Performance
Performance
Typical Values
Outputs
3 Drivers, 2 Pre-drivers, 1 Bidirectional
RDSON @ 25°C
0.2Ω
Operating Voltage
-0.3 to 45 V
Continuous Current
2.0 A for Injector Drivers (1.0A for lamp drivers)
Control
Parallel
ESD, HBM
±2000V
Operating Temperature (TA)
-40°C to +125°C
Junction Operating Temperature (TJ)
-40°C to +150°C
Protection
Protection
Detect
Over-voltage
z
Over-current/SC
z
Over-temperature
z
Open Load
z
Limiting
z
Shut Down
Auto Retry
z
z
z
z
Status
Reporting
z
z
z
z
Simplified Internal Block Diagram
VPWR
VCC
TM_EN
~50 µA
LOGIC CONTROL
TEST1
TEST2
IGNSUP
Ignition
IGNFB
Pre-driver
Band Gap
Oscillator
Bias
TEST3
~50 µA
INJIN
VCCREF
VCCSENS
VPWR, VCC
V10.0 Analog
V2.5 Logic
POR, over-voltage
under-voltage
IGNOUTH
Short
Protection
IGNOUTL
Relay and
Injector Output
INJOUT
PGND1
VCC ~50 µA
Gate Control
~50 µA
INJFLT
IGNIN
~50 µA
VCC
VCC
~50 µA
PARALLEL
CONTROL
VClamp
Current Limit
Temperature Limit
Short Protection
Open det. on Injector
ROUT
PGND2
+
–
~50 µA
IGNFLT
~75µA
RS
lLimit
RIN
RELFLT
Lamp Output
LAMPIN
~50 µA
Gate Control
~50 µA
RESET
WATCHDOG
(Open Drain)
Current Limit
Temperature Limit
Short Protection
~50 µAVCC
MTX
VClamp
+
–
WDRFSH
~50 µA
LAMPOUT
RS
lLimit
GND
ISO9141
CONTROLLER
VCC
MRX
DGND ~50 µA
~50 µA
*Note: Pull up and pull down current sources are ~50 µA unless otherwise noted
ISO9141
WD_INH
Why you need Freescale!
• Are you designing an application for a
small engine?
• Is your local government planning to
issue environmental regulations
regarding small engines?
• Are you planning to move from a
mechanical to an electrical engine
control system?
• Do you need a reference design for a
transition from mechanical to an
electrical engine control system?
• Are you limited for space in your current
electronically controlled small engine?
• Are you looking to consolidate/integrate
multiple functions into a single IC?
Ordering Information
Part Number
Temperature Range
Package
MCZ33812EK/R2
-40°C to +125°C
32 SOICW-EP
* MCZ33812AEK/R2
-40°C to +125°C
32 SOICW-EP
Development Tools
Part Number
Description
KIT33812EKEVBE
Evaluation Board Kit
KIT33812ECUEVME
Reference Design with BDM multi-link
Contact Sales for Evaluation Kit Availability
Document Number
Title
Description
MC33812
Data Sheet
Presents the specifications for the product
SG187
Selector Guide
Automotive Selector Guide
SG1002
Selector Guide
Analog and Mixed Signal Selector Guide
* Note: AEC qualified for automotive applications
32 SOICW-EP
0.65 mm Pitch
11.0 mm x 7.5 mm Body
4.7 mm x 4.7 mm Exposed Pad
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© Freescale Semiconductor, Inc., 2009 - 2010 All rights reserved.
Document Number: MC33812FS, Rev 3.0, 8/2010