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TMS320C6670 Peripheral Information and Electrical Specifications
Copyright 2012 Texas Instruments Incorporated
SPRS689D—March 2012
Multicore Fixed and Floating-Point System-on-Chip
TMS320C6670
5.
Program BWADJ[7:0] in DDR3PLLCTL0 and BWADJ[11:8] in DDR3PLLCTL1 register. BWADJ value must
be set to ((PLLM + 1) >> 1) - 1)
6.
Wait for at least 5 μs based on the reference clock (PLL reset time)
7.
In DDR3PLLCTL1, write PLLRST = 0 (PLL reset is released)
8.
Wait for at least 500 *REFCLK cycles * (PLLD + 1) (PLL lock time)
9.
In DDR3PLLCTL0, write BYPASS = 0 (switch to PLL mode)
CAUTION—
Software must always perform Read-modify-write to any register in the PLL. This is to ensure
that only the relevant bits in the register are modified and the rest of the bits including the reserved bits are
not affected.
7.6.4 DDR3 PLL Input Clock Electrical Data/Timing
Figure 7-24
DDR3 PLL DDRCLK Timing
7.7 PASS PLL
The PASS PLL generates interface clocks for the Network Coprocessor. Using the PACLKSEL pin the user can select
the input source of PASS PLL as either the output of Main PLL mux or the PASSCLK clock reference sources. When
coming out of power-on reset, PASS PLL comes out in a bypass mode and needs to be programmed to a valid
frequency before being enabled and used.
Table 7-29
DDR3 PLL DDRCLK(N|P) Timing Requirements
(see
and
No.
Min
Max
Unit
DDRCLK[P:N]
1
tc(DDRCLKN)
Cycle time _ DDRCLKN cycle time
3.2
25
ns
1
tc(DDRCLKP)
Cycle time _ DDRCLKP cycle time
3.2
25
ns
3
tw(DDRCLKN)
Pulse width _ DDRCLKN high
0.45*tc(DDRCLKN)
0.55*tc(DDRCLKN)
ns
2
tw(DDRCLKN)
Pulse width _ DDRCLKN low
0.45*tc(DDRCLKN)
0.55*tc(DDRCLKN)
ns
2
tw(DDRCLKP)
Pulse width _ DDRCLKP high
0.45*tc(DDRCLKP)
0.55*tc(DDRCLKP)
ns
3
tw(DDRCLKP)
Pulse width _ DDRCLKP low
0.45*tc(DDRCLKP)
0.55*tc(DDRCLKP)
ns
4
tr(DDRCLKN_250 mv) Transition time _ DDRCLKN rise time (250 mV)
50
350
ps
4
tf(DDRCLKN_250 mv) Transition time _ DDRCLKN fall time (250 mV)
50
350
ps
4
tr(DDRCLKP_250 mv)
Transition time _ DDRCLKP rise time (250 mV)
50
350
ps
4
tf(DDRCLKP_250 mv)
Transition time _ DDRCLKP fall time (250 mV)
50
350
ps
5
tj(DDRCLKN)
Jitter, peak_to_peak _ periodic DDRCLKN
0.025*tc(DDRCLKN)
ps
5
tj(DDRCLKP)
Jitter, peak_to_peak _ periodic DDRCLKP
0.025*tc(DDRCLKP)
ps
End of Table 7-29
4
3
2
1
5
DDRCLKN
DDRCLKP
Содержание TMS320C6670
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