Document Number: MC33970
Rev. 3.0, 1/2007
Dual Gauge Driver Integrated
Circuit with Improved Damping
This 33970 is a single-packaged, Serial Peripheral Interface (SPI)
controlled, dual step motor gauge driver integrated circuit (IC). This
monolithic IC consists of four dual output H-Bridge coil drivers and the
associated control logic. Each pair of H-Bridge drivers is used to
automatically control the speed, direction, and magnitude of current
through the two coils of a two-phase instrumentation step motor,
similar to an MMT-licensed AFIC 6405.
The 33970 is ideal for use in automotive instrumentation systems
requiring distributed and flexible step motor gauge driving. The
device also eases the transition to step motors from air core motors
by emulating the air core pointer movement with little additional
processor bandwidth utilization.
IMPROVED GAUGE DRIVER
EG SUFFIX (Pb-FREE)
• MMT-Licensed Two-Phase Step Motor Compatible
• Minimal Processor Overhead Required
• Fully Integrated Pointer Movement and Position State Machine
with Air Core Movement Emulation
• 4096 Possible Steady State Pointer Positions
• 340° Maximum Pointer Sweep
• Fixed Maximum Acceleration and Deceleration of 4500°/s2
-40°C to 125°C
• Maximum Pointer Velocity of 400°/s
• Analog Microstepping (12 Steps/Degree of Pointer Movement)
• Pointer Calibration and Return to Zero
• SPI-Controlled 16-Bit Word
• Calibratable Internal Clock
• Low Sleep Mode Current
• Backward Compatible with MC33991
• Improved Pointer Movement, Diagnostics, and Return to Zero (RTZ)
• Pb-Free Packaging Designated by Suffix Code EG
Figure 1. 33970 Simplified Application Diagram
* This document contains certain information on a new product.
Specifications and information herein are subject to change without notice.
© Freescale Semiconductor, Inc., 2007. All rights reserved.