Multicore Fixed and Floating-Point System-on-Chip
Copyright 2012 Texas Instruments Incorporated
TMS320C6670 Peripheral Information and Electrical Specifications
147
SPRS689D—March 2012
TMS320C6670
3.
In PASSPLLCTL1, write PLLRST = 1 (PLL is reset)
4.
Program PLLM and PLLD in PASSPLLCTL0 register
5.
Program BWADJ[7:0] in PASSPLLCTL0 and BWADJ[11:8] in PASSPLLCTL1 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 PASSPLLCTL1, write PLLSELECT = 1 (for selecting the output of PASS PLL as the input to PASS)
8.
In PASSPLLCTL1, write PLLRST = 0 (PLL reset is released)
9.
Wait for at least 500 * REFCLK cycles * (PLLD + 1) (PLL lock time)
10.
In PASSPLLCTL0, 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.
7.7.4 PASS PLL Input Clock Electrical Data/Timing
Figure 7-28
PASS PLL Timing
Table 7-32
PASS PLL Timing Requirements
)
No.
Min
Max
Unit
PASSCLK[P:N]
1
tc(PASSCLKN)
Cycle time _ PASSCLKN cycle time
3.2
6.4
ns
1
tc(PASSCLKP)
Cycle time _ PASSCLKP cycle time
3.2
6.4
ns
3
tw(PASSCLKN)
Pulse width _ PASSCLKN high
0.45*tc(PASSCLKN)
0.55*tc(PASSCLKN)
ns
2
tw(PASSCLKN)
Pulse width _ PASSCLKN low
0.45*tc(PASSCLKN)
0.55*tc(PASSCLKN)
ns
2
tw(PASSCLKP)
Pulse width _ PASSCLKP high
0.45*tc(PASSCLKP)
0.55*tc(PASSCLKP)
ns
3
tw(PASSCLKP)
Pulse width _ PASSCLKP low
0.45*tc(PASSCLKP)
0.55*tc(PASSCLKP)
ns
4
tr(PASSCLKN_250mv)
Transition time _ PASSCLKN rise time (250 mV)
50
350
ps
4
tf(PASSCLKN_250mv)
Transition time _ PASSCLKN fall time (250 mV)
50
350
ps
4
tr(PASSCLKP_250mv)
Transition time _ PASSCLKP rise time (250 mV)
50
350
ps
4
tf(PASSCLKP_250mv)
Transition time _ PASSCLKP fall time (250 mV)
50
350
ps
5
tj(PASSCLKN)
Jitter, peak_to_peak _ periodic PASSCLKN
100
ps, pk-pk
5
tj(PASSCLKP)
Jitter, peak_to_peak _ periodic PASSCLKP
100
ps, pk-pk
4
3
2
1
5
PASSCLKN
PASSCLKP
Summary of Contents for TMS320C6670
Page 225: ......
