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Mixed Signal FPGA for Under a Buck

Cypress MicroSystems Inc., a subsidiary of Cypress Semiconductor Corporation announced production shipments of its smallest and most highly integrated Programmable System-on-ChipTM (PSoCTM) mixed-signal array. In addition to four configurable analog blocks and four configurable digital blocks, the CY8C21x34 devices provide eight Kbytes of flash memory for program storage and 512 bytes of SRAM for data, making it ideal for cost-sensitive consumer and industrial control applications such as touch-sensitive control panels, security sensors and control, smart temperature, pressure and flow sensors, large sensor arrays, fan controllers and battery chargers.

The new PSoC's built-in low-Ron 28:1 analog input multiplexer greatly simplifies sensor-control designs. Each of the up to 28 pins has a switch that, when selected, connects it to an analog bus. The bus connects to a configurable analog array which, when combined with on-chip digital resources, enables the creation of complex signal processors.

“The CY8C21x34 offers users the expanded Flash program memory, analog configurability and system integration that they need at a price they can easily afford,” said John McDonald, Vice President of Marketing for Cypress MicroSystems. “This flexibility increases PSoC's core value proposition – and now the already low-priced PSoC solution can further reduce component cost by replacing expensive off-chip multiplexers.”

The CY8C21x34's analog and digital blocks can be configured as 8-bit timers, counters and pulse-width modulators (PWMs). For example, the new device can integrate a full-duplex UART, I2C, SPI, two 10-bit ADCs, and a 28:1 low-Ron analog multiplexer in a single chip, while competing devices require a multi -chip solution. This lowers the overall device count, reduces board size and lowers BOM cost in addition to improving system quality and reliability.

Pricing and Availability

The CY8C21x34, is available in 16 SOIC, 20/28 SSOP and 32 5×5 MLF. It operates between 2.4V and 5.25V from -40 to 85 degrees C. The product is in production and priced as low as $0.99/10,000 units.

About the PSoC Family

A true system-on-a-chip, the PSoC device is a configurable mixed signal array that integrates the microcontroller and related peripheral circuits typically found in an embedded design. Employing easy to use development tools, designers select configurable, well characterized library elements to provide analog functions such as amplifiers, ADCs, DACs, filters and comparators and digital functions such as timers, counters, PWMs, SPI and UARTs. PSoC analog performance is instrumentation-quality – including rail-to-rail inputs, exceptionally low noise, input leakage and voltage offset, programmable gain, and 14-bit ADCs.

In addition to these configurable analog and digital blocks, PSoC devices include a fast 8-bit microcontroller, up to 32KB of Flash memory, 2KB of SRAM, an 8×8 multiplier with 32-bit accumulator, power and sleep monitoring circuits, and hardware I2C communications.

All PSoC devices are dynamically reconfigurable, enabling designers to create new system functions on-the-fly. Re-configuring the same silicon for different functions at different times, designers can achieve more than 120 percent utilization of the die in many cases. In the automotive PSoC LIN bus reference design, the same digital blocks are re-configured four times to support the different LIN communication modes; in doing so, these blocks consume less than 10 percent of PSoC hardware resources and less than 10 percent of the PSoC MCU cycles.

Software and Support
A CY8C21x34-specific service pack is downloadable free from the Cypress Semiconductor website. This service pack is an enhancement to the company's existing software development environment, PSoC Designer 4.2.

The software development environment, PSoC Designer 4.2 is a full-featured, GUI-based design tool suite that enables the user to configure their design in silicon with simple point and click options; code the MCU in either C or assembly language; and debug the design using sophisticated features such as event triggers and multiple break points while single-stepping through the code in C or assembly or a mix of the two. PSoC Designer 4.2 is free and can be downloaded by clicking here.

The new CY3215-DK Professional Class Development Kit includes a tiny full-speed in-circuit USB-based emulator with a large trace buffer, which seamlessly integrates with PSoC Designer 4.2 and the user's development board.” The development kit includes everything necessary to complete a design with the PSoC family of ICs. The kits also contain all materials for the first four “Tele-training” classes offered on line by Cypress. The tools are designed for ease of use, to support all the advanced PSoC packages and to keep the cost of development to a minimum while providing all the features found in tools that cost $2,500 or more. The CY3215-DK is priced at $599 (suggested resale).

t's true that the cost per gate of PLDs and FPGAs has been on a steep downward slope for the last several years. The advances in process technology have allowed smaller die sizes to hold more logic with higher performance and less cost. In addition, architectural enhancements have transitioned most of the high density FPGAs from complex registered and combinatorial logic blocks into smaller, more granular look up table (LUT) architectures.

Analog is a different ball game though. As fabrication geometry's get smaller and smaller, analog resolution gets worse, not better. What's more, smaller analog silicon topologies are more susceptible to noise, cross talk, and induced effects. This is exacerbated when small feature sized analog lives side by side with high speed digital.

As a result, more care must be taken at every step of the way when doing a mixed signal design compared to a pure digital or even a pure analog ASIC, board, or system. The other result is that unless you are brave and rich enough to undertake a mixed signal ASIC design, you won't gain the integration and space saving benefits.

That's one reason I'm impressed by the latest PSoC device From Cypress. Check out all that's packed inside this part. In addition to the four configurable analog blocks and four configurable digital blocks, the new CY8C21x34 devices provide eight Kbytes of flash memory for program storage and 512 bytes of SRAM. There is also a built-in low-Ron 28:1 analog input multiplexor. Each of the up to 28 pins has a switch that, when selected, connects it to an analog bus. The bus connects to a configurable analog array which, when combined with on-chip digital resources, enables the creation of complex signal processors.

The digital blocks are not just gates and flip flops. They can be configured as 8-bit timers, counters and pulse-width modulators (PWMs), as well as registered and combinatorial logic. According to Cypress, the digital logic on these parts can implement a full-duplex UART, I2C, SPI, two 10-bit ADCs.

I like the fact that the PSoC devices are dynamically reconfigurable on the fly. This is a serious benefit to the dynamic world of analog. These parts are ideally suited for the many cost-sensitive consumer and industrial control applications. They are low cost enough to find their way into fan controllers and battery chargers, and, sophisticated enough to be used as touch screen controllers and signal processing elements. This also lets them live and play in a dynamic analog function like AGC since the on the fly adjustments can be non volatile.

The family is growing and other PSoC devices house a fast 8-bit microcontroller, up to 32KB of Flash memory, 2KB of SRAM, an 8×8 multiplier with 32-bit accumulator, power and sleep monitoring circuits, and hardware I2C communications.

The analog functionality is not meager either. In addition to the digital offerings the amplifiers, comparators, ADCs, DACs, and filters are instrumentation-quality according to Cypress including rail-to-rail inputs, exceptionally low noise, input leakage and voltage offset, programmable gain, and 14-bit ADCs.

The CY8C21x34, is available now in 16 SOIC, 20/28 SSOP and 32 5×5 MLF and operates between 2.4V and 5.25V from -40 to 85 degrees C. The product is in production and priced as low as $0.99/10,000 units.

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