Motorola Introduces Flexible I/O Expansion IC for Microcontroller-based Systems
One IC adds switch monitoring, LED and FET drivers, and programmable wake-up to low pin count MCUs
PHOENIX, March 10 /PRNewswire-FirstCall/ -- With the MC33993 integrated circuit (IC) from Motorola, Inc.'s (NSYE: MOT) Semiconductor Products Sector, designers of multi-voltage embedded systems now have an enhanced option for expanding the capabilities of low pin count microcontrollers (MCUs).
The MC33993's combination of flexible input and output features gives system designers the opportunity to eliminate dozens of discrete and standard linear ICs. In many systems it may be the only device needed besides the MCU and a 3-pin regulator.
The MC33993 interfaces with a MCU through a four-pin serial peripheral interface (SPI) potentially increasing the MCU input/output (I/O) signals by more than five times. By using the analog multiplex feature of the device, up to 22 analog signals may be sent to one MCU analog to digital (A/D) input.
For greater flexibility, the device's 22 I/O pins may be configured to: detect the status of a switch contact, either opened or closed; provide an analog value to a buffered output; drive a light emitting diode (LED) or the gate of a field effect transistor (FET); or, provide switched power to a low current sensor.
The device is also designed to allow logic-level MCUs to directly interface with system voltages from -14 to 26V. This makes the device ideal for a wide variety of automotive, industrial, and commercial applications.
In addition, the MC33993 features a low-current sleep mode. A variety of programmable wake-up options allow the whole system, including the MCU, to operate in a low quiescent current state. This is an important feature for systems such as remote monitoring where current consumption is a critical design factor.
Systems using higher pin-count microprocessors or microcontrollers may also benefit from the high level of integration and reduced parts count the device can enable.
The MC33993 offers a wide range of features including:
- 22 switch inputs -- 14 switch-to-ground inputs and 8 programmable
switch-to-power or switch-to-ground inputs
- Digital multiplexing via the SPI
- 22 to 1 analog multiplexer
- Contact wetting for switch reliability
- Multiple device connection in daisy-chain fashion using the SPI
- Switch pins capable of driving LEDs or external FETS
- 25KV ESD (electro-static discharge) capable
- Low-power wake up on switch state change
- Timer for wake up
- 3.3V and 5V I/O MCU interface
Manufactured with Motorola's SMARTMOS(TM) manufacturing process, the MC33993 device combines high-density, high-speed logic with precision analog and high-voltage, high-current power circuitry.
Advantages Over Discrete Components
Switches are found in virtually every electronic product or system from automotive dashboard displays to computers to vending machines. The MC33993 is suited for virtually any system or product in which multiple switches are used.
In many systems, designers use resistors and capacitors to interface switches to the system's MCU. These passive components step down the voltage to MCU-level inputs, provide transient filtering, and protect the MCU from electro-static discharge. The MC33993 eliminates these passive components while offering a wider input voltage range and greater MCU protection.
The device is also designed to provide a contact-wetting current to the contacts of the switch. The wetting current acts as a contact cleaner, eliminating oxide build up which would otherwise change the integrity of the switch. This is especially useful in products or systems, such as industrial switch panels or in outdoor installations and other harsh environments.
The contact-wetting feature can be used to provide up to 16 mA of output current to each of the switch input pins. This allows the device to drive LEDs, the gates of FETs or provide switched power to sensors or other devices in the system.
Price and Availability
The MC33993 multiple switch detection interface IC is housed in a 32-lead SOIC (small outline integrated circuit) package and is currently available in sample and production quantities. Unit pricing starts at US$1.50 (suggested list price) for 10,000-piece quantities.
Motorola offers an evaluation board engineered to help reduce customers' system development cycle times. The evaluation board (part number KIT33993DHEVB) is available now for US$99.00 (suggested list price) and includes Motorola's SPIGen graphical user interface software and documentation.
About Motorola Semiconductors
As the world's #1 producer of embedded processors, Motorola's Semiconductor Products Sector creates DigitalDNA system-on-chip solutions for a connected world. Our strong focus on wireless communications and networking enables customers to develop smarter, simpler, safer and synchronized products for the person, work team, home and automobile. Motorola's worldwide semiconductor sales were $4.8 billion (USD) in 2002. For more information please visit http://www.motorola.com/semiconductors
About Motorola
Motorola, Inc. (NYSE: MOT) is a global leader in providing integrated communications and embedded electronic solutions. Sales in 2002 were $26.7 billion. Motorola is a global corporate citizen dedicated to ethical business practices and pioneering important technologies that make things smarter and life better for people, honored traditions that began when the company was founded 75 years ago this year. For more information, please visit: www.motorola.com
Reader Inquiry Response:
Motorola SPS
P.O. Box 17927
Denver, CO 80217 USA
MOTOROLA and the Stylized M Logo are registered in the US Patent & Trademark Office. All other product or service names are the property of their respective owners.
Except for historical information, all of the expectations and assumptions, contained in the foregoing are forward-looking statements involving risk and uncertainties. Important factors that could cause actual results to differ materially from such forward-looking statements, include, but are not limited to, the competitive environment for our products, changes of rates of all related services, and legislation that may affect the industry. For additional information regarding these and other risks associated with Company's business refer to the Company's reports with the SEC.
CONTACT: Media -- North America - Brian Thorsen, +1-480-413-5209 or
brian.thorsen@motorola.com, or Europe, Middle East, Africa - Regina Cirmonova,
+41-22-799-1258 or regina.cirmonova@motorola.com, or Asia/Pacific - Gloria
Shiu, +852-2666-8237 or gloria.shiu@motorola.com, or Latin America - Jill
Partridge, +1-602-952-3078 or jill.partridge@motorola.com, all of Motorola; or
Emilie Harris of Lois Paul & Partners, +1-512-638-5321 or
emilie_harris@lpp.com for Motorola
Web site: http://www.motorola.com/
|
