Nov 4 2008
Liquid crystal displays (LCDs) are proliferating in an ever-growing array of consumer and industrial products. To help meet the demand for efficient, affordable LCDs, Freescale Semiconductor has introduced three 8-bit microcontroller (MCU) families designed to reduce system cost and power in LCD-based embedded applications.
The new Freescale LCD MCUs include the S08LL, RS08LA and RS08LE families. The L family devices offer industry-leading LCD capabilities and ultra-low-power options at affordable price points. The 8-bit MCUs are designed to address a wide range of cost- and power-sensitive LCD-based designs, from battery-backed handheld devices to wireless systems. Target applications include thermostats, meters, timers, security systems, rice cookers, coffee machines and other small consumer appliances.
L family MCUs are also ideally suited for personal diagnostic and portable health care products, such as glucose meters and pulse oximeters, which require low power operation and advanced display capabilities. The S08LL family is ideal for these applications due to its exceptional standby power consumption and multiplexed LCD driver functionality, which enables smaller designs with higher segment count.
Featuring an integrated LCD driver, L family MCUs eliminate the need for separate display driver ICs for both standard 3V and 5V LCD glass applications. The on-chip LCD drivers support up to eight backplanes, enabling developers to drive more segments with fewer pins and thus reduce system cost and design complexity. The L family supports an LCD blink mode that operates without waking up the controller core, which helps reduce overall power consumption.
“Freescale’s L family MCUs widen the range of cost-effective, ultra-low-power solutions within Freescale’s extensive LCD MCU portfolio,” said Aiden Mitchell, director of industrial and multi-market microcontrollers at Freescale. “Freescale offers the right choice of 8-bit devices for designers of battery-backed and wireless systems that require LCD support. L family MCUs provide many options for LCD segment drivers, package sizes and integrated features, giving developers greater design flexibility.”
S08LL family
The MC9S08LL16/8 devices combine an integrated LCD driver with best-in-class, ultra-low-power performance for embedded applications with LCD screens. The S08LL devices are designed to enhance portable performance, extend battery life and improve energy efficiency for a wide range of battery-operated applications and low-power devices. The S08LL family’s internally regulated voltage capability enables software contrast control, which reduces the need for extra components and extends temperature and operating voltage ranges.
Using Freescale's ultra-low-power platform, along with an LCD peripheral optimized for low power, the LL16 has achieved best-in-class standby power consumption. The LL16 supports a wide range of operation modes that can allow as low as 1.3 microamps to 6.1 microamps when driving LCD displays.
Additional S08LL device features include:
- Two ultra-low-power stop modes
- New low-power run and wait modes
- Six microsecond wake-up time
- Ultra-low-power oscillator
- Configurable 8 x 24 or 4 x 28 segment display
- Internal charge pump
- Software selectable frontplane and backplane
- RS08LA and RS08LE families
The cost-effective MC9RS08LA8 and MC9RS08LE4 families are based on Freescale’s RS08 core and are intended for small appliances, medical monitoring equipment and other low-power industrial applications. The RS08LA family features Freescale’s first entry-level LCD MCUs in the sub-$1 (USD) price range, targeting cost-sensitive LCD applications. The devices are designed to help reduce the cost of existing LCD-based products and enable developers to add basic LCD functionality to applications.
The RS08LE family provides an ultra-affordable 8-bit migration path for LCD-based products currently using 4-bit MCUs that cannot meet the performance requirements of today’s embedded applications. Offering the industry’s lowest pin count LCD devices (28-pin SOIC package), the RS08LE family is capable of driving 112 LCD segments and can be used to replace less powerful 4-bit LCD drivers.
Key features for the RS08LA and RS08LE families include:
- HCS08 instruction set with added BGND instruction
- Configurable displays
- 8 x 21 or 4 x 25 (LA8)
- 8 x 14 or 4 x 18 (LE4)
- Power-saving ability to drive display while CPU sleeps
- Internal charge pump (LA8 only)
- Software-selectable frontplane and backplane
- Pin and software compatibility
Freescale’s broad portfolio of software-configurable LCD devices offers pin compatibility options and shares peripherals to enhance design flexibility. Pin compatibility between the S08LL and RS08LA families enables scalability for end applications with the option to use the S08 core with the LL family or the RS08 core with the LA family. This compatibility provides a migration path to evaluate different performance options. Because the S08 and RS08 devices share the same LCD peripheral, developers can create software applications that are easily portable across the families.
LCD design made easy
Freescale L family MCUs are backed by a comprehensive ecosystem of development tools, reference designs, application notes, software examples and Web casts. The L family devices are supported by a complimentary version of CodeWarrior® Development Studio for Microcontrollers v6.2, an integrated tool suite that supports software development for Freescale’s 8-bit or 32-bit MCUs. Designers can further accelerate application development with the help of the Processor Expert™ tool, an award-winning rapid application development tool in the CodeWarrior tool suite.
To help developers explore the features and capabilities of the L family devices, Freescale offers the DEMO9S08LL16, DEMO9RS08LA8 and DEMO9RS08LE4 evaluation systems.