Power Management Design Guide for Altera® FPGAs and CPLDs ...

National power solutions for Cyclone FPGAs
Cyclone FPGAs
Altera’s Cyclone series of FPGAs provides the benefits of
programmable logic at price points competitive with ASICs
and ASSPs. Built from the ground up based on extensive
input from hundreds of customers, these low-cost devices
provide high-volume, application-focused features such as
embedded memory, external memory interfaces, and clock
management circuitry. Based on the cost-optimized all-layer
copper 1.5V SRAM process, Cyclone FPGAs are available
in densities ranging from 2,910 to 20,060 logic elements
(LEs) with up to 294,912 bits of embedded RAM.
Cyclone FPGAs support a variety of single-ended I/O
standards such as LVTTL, LVCMOS, PCI, and SSTL-2/3
and offer differential I/O support via the LVDS and RSDS
I/O standards on up to 129 channels. Each channel is
capable of operating LVDS signals at up to 640 Mbps.
Cyclone devices feature dedicated circuitry to implement
double data rate (DDR) SDRAM and FCRAM interfaces.
LM2734/36 1A SOT-23 buck regulators
• Complete, easy-to-use switcher solution has
smallest footprint and highest power density in
the industry
• State-of-the-art 13 ns minimum ON-time allows
for high conversion ratios without the need to
reduce switching frequency or increase solution size
• Choice of switching frequencies allows designers
to trade off efficiency against solution size and EMI
• Current mode control improves phase margin, line
regulation and rejection of transients
• PWM provides a predictable, easily filtered
switching frequency for reduced output noise
• Internal softstart circuitry, cycle-by-cycle, thermal
shutdown, and over-voltage protection
• Available in TSOT-23 packaging (1.0 mm height)
The core of these FPGAs needs to be powered from a 1.5V
source. Core current consumption (I CCINT ) depends upon
utilization of the part (such as clock speed and internal
elements used), but maximum values range from 0.75A
to 5A (approx.) depending on the specific Cyclone device
used. To calculate the most accurate power consumption
values needed by a specific design, use Altera’s Power
Calculator tool (see www.national.com/see/alterafpga). As
a general rule, choose a V CCINT power supply whose I OUT
(I CCINT ) capability is within the I CCINT inrush and I CCINT
maximum values given in this guide for the specific Altera
device used.
Another power management consideration is the monotonic
rise of V CCINT . This consideration is critical for the correct
operation of the FPGA. While many power supplies take
this requirement into consideration, it is recommended to
further support this requirement by the use of adequate
bulk capacitance in the power supply.
LM2734 Simple block diagram
Feature LM2734 LM2736
Input range 3.0V to 20V 3.0V to 18V
Output load 1A 750 mA
Output range 0.8V to 18V 1.25V to 16V
Internal references 0.8V, 2% 1.25V, 2%
Operating frequency
550 kHz / 1.6 MHz / 3 MHz
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