5–6
Chapter 5: Clock Networks and PLLs in the Cyclone III Device Family
Clock Networks
GCLK Network Clock Source Generation
Figure 5–2 shows Cyclone III device family PLLs, clock inputs, and clock control
block location for different device densities.
(1)
Figure 5–2. PLL, CLK[], DPCLK[], and Clock Control Block Locations in the Cyclone III Device Family
DPCLK[11.10]
DPCLK[9..8]
CDPCLK7
CDPCLK6
CLK[11..8]
2
2
4
4
(3)
PLL
2
PLL
3
4
5
CDPCLK0
CDPCLK5
(3)
(2)
(2)
2
4
4
Clock Control
Block (1)
5
2
GCLK[19..0]
20
DPCLK0
DPCLK7
CLK[7..4]
DPCLK6
20
20
CLK[3..0]
DPCLK1
4
4
20
GCLK[19..0]
Clock Control
Block (1)
2
4
4
5
2
4
(2)
(2)
(3)
CDPCLK4
CDPCLK1
5
PLL
4
PLL
1
(3)
4
4
2
2
CDPCLK3
CDPCLK2
CLK[15..12]
DPCLK[3..2]
DPCLK[5..4]
Notes to Figure 5–2:
(1) There are five clock control blocks on each side.
(2) Only one of the corner CDPCLKpins in each corner can feed the clock control block at a time. You can use the other CDPCLKpins as
general-purpose I/O pins.
(3) Remote clock pins can feed PLLs over dedicated clock paths. However, these paths are not fully compensated.
Cyclone III Device Handbook
Volume 1
July 2012 Altera Corporation