MT8889C/MT8889C-1

4-122

† Characteristics are over recommended operating conditions unless otherwise stated

NOTES: 1) dBm=decibels above or below a reference power of 1 mW into a 600 ohm load.

2) Digit sequence consists of all 16 DTMF tones.

3) Tone duration=40 ms. Tone pause=40 ms.

4) Nominal DTMF frequencies are used.

5) Both tones in the composite signal have an equal amplitude.

6) The tone pair is deviated by ± 1.5 %±2 Hz.

7) Bandwidth limited (3 kHz) Gaussian noise.

8) The precise dial tone frequencies are 350 and 440 Hz (±2 %).

9) Guaranteed by design and characterization. Not subject to production testing.

10) Referenced to the lowest amplitude tone in the DTMF signal.

11) For guard time calculation purposes.

Figure 16 - DS/RD/WR Clock Pulse

Characteristics

Sym

Min

Max

Units

Conditions

1DS/RD/WR clock frequency

4.0

MHz

Figure 16

2DS/RD/WR cycle period

250

ns

Figure 16

3DS/RD/WR low pulse width

150

ns

Figure 16

4DS/RD/WR high pulse width

100

ns

Figure 16

5DS/RD/WR rise and fall time

20

ns

Figure 16

6R/W setup time

23

ns

Figures 17 & 18

7R/W hold time

20

ns

Figures 17 & 18

8

Address setup time (RS0)

0

ns

Figures 17 - 20

9

Address hold time (RS0)

40

20

ns

Figures 17 - 20

10

Data hold time (read)

22

ns

Figures 17 - 20

11

DS/RD to valid data delay (read)

100

ns

Figures 17 - 20

12

Data setup time (write)

45

ns

Figures 17 - 20

13

Data hold time (write)

10

ns

Figures 17 - 20

14

Chip select setup time

45

35

ns

Figures 17 - 20

15

Chip select hold time

40

ns

Figures 17 - 20

16

Input Capacitance (data bus)

5pF

17

Output Capacitance (IRQ/CP)

5pF

DS/RD/WR