TMS320C25-50

SPRS010B Ð MAY 1987 Ð REVISED NOVEMBER 1990

TMS320C25

CLKIN

 

+5 V

fcrystal

 

 

 

10 kΩ

 

 

74HC04

4.7 kΩ

F11

 

 

 

 

47 pF

74AS04

 

 

10 kΩ

 

fcrystal, (MHz)

L, (H)

TMS320C25

40.96

1.8

TMS320C25-50

51.20

1.0

TMS320E25

40.96

1.8

 

 

 

C = 20 pF

0.1F

L

ADVANCE INFORMATION

Figure 7. External Clock Option

timing requirements over recommended operating conditions (see Note 3)

 

 

 

MIN

NOM MAX

UNIT

 

 

 

 

 

 

tc(CI)

CLKIN cycle time

19.5

150

ns

3

 

 

 

 

 

 

 

 

 

 

 

t

CLKIN fall time

 

5 ²

ns

f(CI)

 

 

 

 

 

t

CLKIN rise time

 

5²

ns

r(CI)

 

 

 

 

 

tw(CIL)

CLKIN low pulse duration, tc(CI) = 50 ns (see Note 4)

20

 

ns

tw(CIH)

CLKIN high pulse duration, tc(CI) = 50 ns (see Note 4)

20

 

ns

tsu(S)

 

setup time before CLKIN low

4

Q ± 4

ns

SYNC

th(S)

 

hold time from CLKIN low

4

 

ns

SYNC

 

²Value derived from characterization data and not tested.

NOTES: 3. Q = 1/4 tc(C)

4. CLKIN duty cycle [tr(CI) + tw(CIH)]/tc(CI) must be within 40-60%.

36

POST OFFICE BOX 1443 HOUSTON, TEXAS 77001

Page 36
Image 36
Texas Instruments TMS320 specifications Fcrystal