In a programmable logic world increasingly populated by FPGAs, is there still a place for the humble Complex Programmable Logic Devices (CPLD)? Well, the folks at Lattice Semiconductor certainly think so.
The CPLD's inherent non-volatility and small form factor make it ideal for implementation in portable, hand-held devices. Ideal, that is, except for the power consumption associated with conventional CPLD's.
In order to address this, the folks at Lattice have just announced their latest generation of zero-power CPLDs, devices with an expanded feature set that they say: "Reduces power consumption like no other CPLD ever has!"
This second-generation in-system programmable CPLD family – the ultra-low-power 1.8-volt ispMACH 4000ZE family – is ideal for low power, high volume portable applications, with typical standby current as low as 10 µA.
The cost optimized and feature rich ispMACH 4000ZE devices offer ultra-small, space saving chip scale Ball Grid Array (csBGA) package options, a new Power Guard feature that provides ultra-low system power, and new system integration capabilities, including an on-chip user oscillator and timer.
The ispMACH 4000ZE family will be offered in four logic densities, from 32 to 256 macrocells. Samples of the first two devices, the 32-macrocell ispMACH 4032ZE and the 64-macrocell ispMACH 4064ZE, are available now.
New system features
The ispMACH 4000ZE family offers enhanced system features such as Power Guard dynamic power reduction; per pin pull-up, pull-down or bus keeper control; an on-chip user oscillator and timer; and input hysteresis.
The Power Guard feature lowers power consumption by selectively disabling unused input pins so their switching does not consume dynamic power needlessly. This feature consists of an enabling multiplexer between the I/O pin and the input buffer and its associated circuitry inside the device. All I/O pins in a block share a common Block Input Enable (BIE) signal. Depending on the device size, there can be from 2 to 16 blocks per device. Any I/O pin in the block can be programmed to ignore the BIE signal, allowing the Power Guard feature to be enabled or disabled on a pin-by-pin basis.
An internal oscillator also is provided for use in miscellaneous housekeeping functions such as watchdog "heartbeat" functions, digital de-glitch circuits and control state machines. The ispMACH 4000ZE family also offers "always on" input hysteresis for each pin. This new feature provides improved noise immunity for 3.3V and 2.5V inputs.
Ultra-small space-saving packages
The ispMACH 4000ZE family is available in space saving 0.5-millimeter ball pitch 64-ball and 144-ball csBGA packages. These small PCB-footprint packages, five millimeters square and seven millimeters square, respectively, satisfy the tight space constraints often found with portable and handheld equipment.
The ispMACH 4000ZE family is also offered in more traditional 48-pin, 100-pin and 144-pin TQFP packages, and supports system designers' need for density migration within a common package/pinout footprint across multiple device densities. The ispMACH 4000ZE devices are also pin-compatible with Lattice's earlier ispMACH 4000Z devices in corresponding packages. All ispMACH 4000ZE family package options are Pb-free and RoHS compliant.
Power supply and I/O standard support
The ispMACH 4000ZE devices operate from a nominal 1.8-volt power supply with operation extended down to 1.6-volts, accommodating extended end-of-battery-life voltages that can provide useful added margin for many systems.
The ispMACH 4000ZE devices have two I/O banks, each with its own power supply voltage that can be set at the appropriate level to support LVTTL and LVCMOS 3.3, 2.5, 1.8 and 1.5-volt outputs. The device input buffers have programmable thresholds that support the above standards independent of the I/O bank voltage.
Extended range 3.3-volt I/O current is supported, instead of the more common narrow range version. The I/Os on the ispMACH 4000ZE devices are 5-volt tolerant to facilitate connection to legacy chips and interfaces. All ispMACH 4000ZE devices are Boundary Scan Testable and in-system programmable through an IEEE 1532-compliant JTAG boundary scan (IEEE 1149.1) interface.
Pricing and availability
The ispMACH 4032ZE CPLD is available in the 48-TQFP and 64-ball csBGA package. The ispMACH 4064ZE CPLD is available in the 48-TQFP, 64-ball csBGA, 100-TQFP and 144-ball csBGA. Both devices are sampling now and are available in both commercial and industrial temperature options.
The entire ispMACH 4000ZE family is expected to be released mid-2008. Projected pricing for the ispMACH 4032ZE is less than $0.70 in 100,000 piece quantities; and for the ispMACH 4064ZE less than $0.85 in 100,000 piece quantities.