MAS6240C2HP06 低噪声/EMI压电蜂鸣器驱动器

技术规格

电源电压（最大） Supply Voltage (maximum)	3.3V
电源电压（最低） Supply Voltage (minimum)	2.2V
电源电流 Supply Current	1.5mA
静态电流 Quiescent Current	1µA
V输出最大值 V-out max	18V
最大 fo-max	0.008MHz
待机 Standby	Yes

详细描述

MAS6240 是一种压电驱动器设备，可以从 3V 电源驱动高达 18Vpp 的输出。内部三模式电荷泵为压电驱动器产生升压电源电压。为了调节压电元件的音量，电荷泵可以在 1x、2x 或 3x 模式下运行。在 1x 模式下，输出电压与输入电压相同，而在 2x 或 3x 模式下，输入电压相应地升高。

MAS6240 是一种简单且低成本的 peizo 驱动器解决方案，因为除了声音元件之外只需要 4 个小容量电容器。不需要电感器。这种设计还大大减少了对周围电路的干扰，使其成为敏感设计的理想选择。其电荷泵以 1MHz 开关，允许使用小至 100nF 的外部电容器。

控制逻辑在数字输入 (DIN) 引脚的第一个上升信号时打开电荷泵。当 DIN 上的信号一直处于低电平 50ms 时，就会产生关断信号。压电驱动器在 DIN 脉冲的第二个上升沿启用，信号传输到压电输出 VO1。相同的信号被反相为差分输出的输出 VO2。

DIN 输入端的持续高逻辑电平会导致电荷泵开启，但音频放大器处于禁用状态。在这种状态下，电荷泵输出可用于为外部 LED 或任何其他外部电路供电。输出电压仍可分三步选择。在“禁用”模式下（DIN 通常为低电平 15ms），所有功能块都关闭以实现小于 1μA 的静态电流。

The MAS6240 is a piezo driver device that can drive outputs up to 18Vpp from a 3V supply. An internal three-mode charge pump generates a boosted supply voltage for the piezo driver. To adjust the piezo element sound volume, the charge pump can operate in either 1x, 2x or 3x mode. In 1x mode the output voltage is the same as the input voltage while in 2x or 3x mode the input voltage is boosted accordingly.

The MAS6240 is an easy and low-cost peizo driver solution since only 4 small value capacitors are needed in addition to the sound element. No inductors are required. This design also causes significantly less disturbance to the surrounding circuits making it an ideal choice for sensitive designs. Its charge pump switches at 1MHz, allowing the use of external capacitors as small as 100nF.

Control logic switches the charge pump on at the first rising signal of the digital input (DIN) pin. The switch-off signal is generated while the signal at DIN has been low for 50ms. The piezo driver is enabled at a second rising edge of a pulse at DIN and the signal is transferred to piezo output VO1. The same signal is inverted into output VO2 for the differential output.

A continuous high logic level at the DIN input causes the charge pump to be turned ON but leaves the audio amplifier disabled. In that state the charge pump output can be used to power the external LEDs or any other external circuit. The output voltage is still selectable in three steps. In "disabled" mode (DIN has been low for 15ms typically) all functional blocks are switched off to achieve a quiescent current of less than 1μA.