DA6240.001

20 November 2006

5 (10)

DETAILED DESCRIPTION

MAS6240 first pulse skipping

-1

0

1

2

3

4

5

6

7

8

9

10

-20

-10

0

10

20

30

40

50

60

70

time [ms]

VO1

DIN

Figure 3: Enabling output VO1

The piezo driver is enabled at the second rising edge of the pulse at DIN, thus the signal is transferred to the

piezo output VO1. An output VO2 is enabled at the same time, but it is optional to take it in use. Control logic is

switching the charge pump on at first rising signal of digital input DIN pin. If only one continous pulse is fed to the

input DIN, the output VO1 is not enabled. This make it possible to control e.g. a white LED or other device

through pin VOUT while charge pump is enabled, without enabling the piezo output VO1.

MAS6240 first pulse skipping & power down delay

-2

0

2

4

6

8

10

-20

-10

0

10

20

30

40

50

60

70

time [sec]

DIN

VO2

Figure 4: Disabling VO2

Figure 4 is drawn in the case of VO2. The switch-off signal will be generated after the signal at DIN has been low

at least for 10 ms. In the figure 4 the switch-off delay is about 25 ms. Again when new pulses are fed into DIN,

the charge pump and piezo driver will be enabled.