SPRS292A − OCTOBER 2005 − REVISED NOVEMBER 2005
INPUT AND OUTPUT CLOCKS (CONTINUED)
switching characteristics over recommended operating conditions for CLKOUT2†‡ (see Figure 23)
|
|
|
|
| |
|
|
| ZDPA−167 |
| |
NO. |
| PARAMETER | −200 |
| UNIT |
|
|
| −250 |
|
|
|
|
| MIN | MAX |
|
|
|
|
|
|
|
1 | tc(CKO2) | Cycle time, CLKOUT2 | C2 − 0.8 | C2 + 0.8 | ns |
2 | tw(CKO2H) | Pulse duration, CLKOUT2 high | (C2/2) − 0.8 | (C2/2) + 0.8 | ns |
3 | tw(CKO2L) | Pulse duration, CLKOUT2 low | (C2/2) − 0.8 | (C2/2) + 0.8 | ns |
4 | tt(CKO2) | Transition time, CLKOUT2 |
| 2 | ns |
†The reference points for the rise and fall transitions are measured at VOL MAX and VOH MIN.
‡C2 = CLKOUT2 period in ns. CLKOUT2 period is determined by the PLL controller output SYSCLK2 period, which must be set to CPU period
1
4
2
CLKOUT2
3
4
Figure 23. CLKOUT2 Timings
switching characteristics over recommended operating conditions for CLKOUT3†§ (see Figure 24)
|
|
|
| ||
|
|
| ZDPA−167 |
| |
NO. |
| PARAMETER | −200 |
| UNIT |
|
|
| −250 |
|
|
|
|
| MIN | MAX |
|
|
|
|
|
|
|
1 | tc(CKO3) | Cycle time, CLKOUT3 | C3 − 0.9 | C3 + 0.9 | ns |
2 | tw(CKO3H) | Pulse duration, CLKOUT3 high | (C3/2) − 0.9 | (C3/2) + 0.9 | ns |
3 | tw(CKO3L) | Pulse duration, CLKOUT3 low | (C3/2) − 0.9 | (C3/2) + 0.9 | ns |
4 | tt(CKO3) | Transition time, CLKOUT3 |
| 3 | ns |
5 | Delay time, CLKIN high to CLKOUT3 valid | 1.5 | 7.5 | ns |
†The reference points for the rise and fall transitions are measured at VOL MAX and VOH MIN.
‡C3 = CLKOUT3 period in ns. CLKOUT3 period is a
PLL and PLL controller.
CLKIN
CLKOUT3
1
3
2
5
5
4
4
NOTE A: For this example, the CLKOUT3 frequency is CLKIN
Figure 24. CLKOUT3 Timings
POST OFFICE BOX 1443 • HOUSTON, TEXAS 77251−1443 | 69 |