DA6241.005

31 January, 2019

3 (9)

Figure 3. Enable pin controlled single-ended piezo driver - max 9Vpp signal for piezo from 3V supply voltage

Charge pump flying capacitor configurations

The 3x charge pump is configured either to 3x or 2x charge pump operation depending on the flying capacitor

configuration. The 2x operation requires only one flying capacitor (CF) between pins CP2 and CN1. The 3x

operation requires two flying capacitors (CF1, CF2) between CP1 and CN1 and CP2 and CN2 pins respectively.

See figure 4.

Figure 4. 2x and 3x charge pump operation configurations

Piezo drive voltage depends on supply voltage (VIN) and charge pump and piezo load configurations (table 1).

Table 1. Maximum piezo drive voltage [Vpp] at different VIN and charge pump and output load configurations

VIN

2x CHARGE PUMP CONFIG.

3x CHARGE PUMP CONFIG.

SINGLE-ENDED

DIFFERENTIAL

SINGLE-ENDED

DIFFERENTIAL

2.2

4.4

8.8

6.6

13.2

3

6

12

9

18

3.6

7.2

14.4

10.8

21.6