EP1S80B956C7N Altera, EP1S80B956C7N Datasheet - Page 619

• Manufacturer Part Number: EP1S80B956C7N
• Description: IC STRATIX FPGA 80K LE 956-BGA
• Manufacturer: Altera
• Series: Stratix®r

Specifications of EP1S80B956C7N

• Number Of Logic Elements/cells: 79040
• Number Of Labs/clbs: 7904
• Total Ram Bits: 7427520
• Number Of I /o: 683
• Voltage - Supply: 1.425 V ~ 1.575 V
• Mounting Type: Surface Mount
• Operating Temperature: 0°C ~ 85°C
• Package / Case: 956-BGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Number Of Gates: -

Altera Corporation
September 2004
Implementing High Performance DSP Functions in Stratix & Stratix GX Devices
Through the use of integer feedforward multiplies, which can be
implemented by combining addition, shifting, and complimenting
operations, a Butterworth filter’s transfer function biquad can be
optimized for logic synthesis. The most efficient transformation is that of
an all pole filter. This is because there is a unique relationship between the
feedforward integer coefficients of the filter represented as:
As can be seen by this equation, the z
(representing the feedforward path) is twice the other two operands (z
and 1). This is always the case in the transformation from the frequency
to the digital domain. This represents the normalized response, which is
faster and smaller to implement in hardware than real multipliers. It
introduces a scaling factor as well, but this can be corrected at the end of
the cascade chain through a single multiply.
Figure 7–24
Stratix or Stratix GX device.
H z
=
shows how a Butterworth filter biquad is implemented in a
------------------------------------------ -
1
1
+
+
b
1
2z
z
1 –
1 –
+
+
b
z
2
2 –
z
2 –
-1
Stratix Device Handbook, Volume 2
coefficient in the numerator
7–41
-2