PXN20 Datasheet, PDF (54/60 Pages) Freescale Semiconductor, Inc – PXN20 Microcontroller

Electrical characteristics
Table 31. MLB timing for MLB speed 256 Fs or 512 Fs (continued)
Spec
Parameter
Symbol Min
Typ
Max
Unit
Comments
10 MLBSIG/MLBDAT output high
t_mcfdz
0
—
t_mckl
ns
—
impedance from MLBCLK low
11 Bus Hold time³
t_mdzh
4
—
—
ns
—
12 MLBSIG/MLBDAT output valid from t_mcrdv
—
—
8
ns
—
MLBCLK rising
• Ground = 0.0V
• Load Capacitance = 60 pF, SIU_PCR144–SIU_PCR146[DSC] = 0b11.
• MLB speed of 256 Fs or 512 Fs (Fs = 48 kHz)
Unless otherwise noted, all timing parameters are specified from the valid voltage threshold in Table 30.
1 _{The Controller can shut off MLBCLK to place MLB in a low-power state.}
2 _{Pulse width variation is measured at 1.25 V by triggering on one edge of MLBCLK and measuring the spread on the other}
edge, measured in ns peak-to-peak (ns p-p).
3 _{The board must be designed to insure that the high-impedance bus does not leave the logic state of the final driven bit for this}
time period. Therefore, coupling must be minimized while meeting the maximum capacitive load listed.
Table 32. MLB timing for MLB speed 1024 Fs
Spec
Parameter
Symbol Min
Typ
Max
Unit
Comments
1
MLBCLK Operating Frequency¹
f_mck 45.056
—
—
—
49.152
—
1024 Fs at 44.0 kHz
1024 Fs at 48.0 kHz
—
—
49.2544 MHz 1024 Fs at 48.1 kHz
—
—
51.200
1024 Fs PLL unlocked
2 MLBCLK rise time
3 MLBCLK fall time
4 MLBCLK cycle time
5 MLBCLK low time
t_mckr
—
—
1
ns V_IL to V_IH
t_mckf
—
—
1
ns V_IH to V_IL
t_mckc
—
20.3
—
ns V_IL to V_IH
t_mckl
6.5
7.7
6.1
7.3
—
ns 1024 Fs
PLL unlocked
6 MLBCLK high time
7
MLBCLK pulse width variation²
8 MLBSIG/MLBDAT input valid to
MLBCLK falling
t_mckh
9.7
9.3
t_mpwv
—
t_dsmcf
1
10.6
10.2
—
—
—
ns 1024 Fs
PLL unclocked
0.7 ns p-p
—
ns
9
MLBSIG/MLBDAT input hold from t_dhmcf
0
—
MLBCLK low
—
ns
10 MLBSIG/MLBDAT output high
impedance from MLBCLK low
t_mcfdz
0
—
t_mckl
ns
11 Bus Hold time³
t_mdzh
2
—
—
ns
12 MLBSIG/MLBDAT output valid from t_mcrdv
—
—
MLBCLK rising
7
ns
• Ground = 0.0V
• Load Capacitance = 40 pF, SIU_PCR144–SIU_PCR146[DSC] = 0b00.
• MLB speed = 1024Fs (Fs = 48 kHz)
• Unless otherwise noted, timing parameters are specified from the valid voltage threshold in Table 30.
PXN20 Microcontroller Data Sheet, Rev. 1
54
Freescale Semiconductor