FPGAs showcase highest I/O density for programmable devices

A family of 5?W I/O-optimized FPGAs has been launched by Actel Corp. for power-conscious designs. Actel claims that the Igloo Plus family of FPGAs has the industry's best power-, area-, logic-, and feature-per-I/O ratios in programmable devices.

The 5?W I/O-optimized FPGAs offer up to 64 percent more I/Os than the company's original Igloo FPGAs and support independent Schmitt Trigger inputs, hot-swapping, and Flash*Freeze bus hold.

Increase in I/Os
The Igloo Plus family offers up to 64 percent more I/Os than their regular Igloo counterparts, and are targeted at applications requiring low-power with high numbers of I/Os. Thus, it is an ideal solution for portable electronics in consumer, industrial, communications, medical and test applications, particularly those employing I/O-intensive memory bus manipulation, general-purpose I/O expansion, sequencing, interface translation, storage and human interface touch screen and keypad technology.

I/O metrics
For any given package size, Actel say that Igloo Plus devices deliver the industry's best power-, area-, logic- and feature-per-I/O ratios in a programmable device. They claim that an Igloo Plus device delivers 6x better static power consumption, a 50 percent reduction in dynamic power consumption, a 2x improvement in I/O density and as much as 2.7x the logic density compared with competitive programmable logic devices in a similar package.

For example, they say that a competitive SRAM-based programmable solution in an 8mm x 8mm chip-scale package offers 25k equivalent system gates, 78 I/Os, and 25mW typical static power versus the 60k system gates, 157 I/Os and 10?W of an AGLP060 Igloo Plus FPGA in the same package.

The Actel Igloo Plus FPGAs also offer up to 16x better power per I/O. Assuming a design requires 100 I/Os, the 120-I/O AGLP030 Igloo Plus device consumes 5?W versus the roughly 60锟絎 of the nearest competitive solution.

Three devices
Ranging from 30,000 to 125,000 gates, the Igloo Plus family features three 1.2V devices that have been optimized to better meet the needs of I/O-intensive portable applications. In addition to the increase in I/Os per device, the new devices also feature four I/O banks for independent level shifting. Enabling the device to better support varying voltage levels, this is key for bridging between application processors and ASSPs, where differing I/O standards and voltages may be utilized. Igloo Plus devices support cost- and area-effective level shifting between 1.2V, 1.5V, 1.8V, 2.5V and 3.3V I/O standards and interface translation.

Additionally, the Igloo Plus devices support independent Schmitt Trigger inputs and hot swapping. The Schmitt Trigger input delivers greater noise immunity in the circuit, enabling designers to identify safely an input signal that rises slowly, such as a keyboard or human touchpad. The hot swap capability offers additional flexibility as designers can now support direct system connection while powering up. This is beneficial for applications like portable media players and games, where solid-state mass storage modules and human interface controllers are often connected and disconnected from the system in real time.

The Igloo Plus family also supports Flash*Freeze bus hold, allowing users to hold the I/O states "on" even in Flash*Freeze mode. In a digital picture frame, for example, the Igloo Plus device can be placed in Flash*Freeze mode to save power and will continue displaying a picture on screen. When the picture needs to be changed, the device can resume dynamic power in a microsecond, having saved hundreds of microwatts of power while in the I/O hold state. This same capability is critical in smart phone, wireless audio and video applications.

The IGLOO Plus family features devices that have been optimized to meet the needs of I/O-intensive portables

Availability and pricing
Samples of the Igloo Plus devices will be available in May with qualified devices available in Q3 08. The Igloo Plus family is supported by the Actel Libero Integrated Design Environment v8.3 software available in March. Volume pricing starts at $1.95 for the 120-I/O AGLP030 device in a CS201 package.

- Clive Maxfield
Programmable Logic DesignLine