PAM8904Application InformationCharge Pump Mode Setting The Charge Pump Mode (CPM) pins EN1 and EN2 are used to set the charge pump into mode 1x VDD, 2x VDD, 3x VDD or they can be used to put the PAM8904 in to a forced low current shutdown mode. DINEN1EN2MODE 0 — — Shutdown Mode 1 0 0 Shutdown Mode 1 0 1 1x Mode 1 1 0 2x Mode 1 1 1 3x Mode
Care must be taken when using the 3x mode with a VDD supply of 5V or more, as this will force the VOUT to exceed its Absolute Maximum specification (15V). VDD RangeMode 2.3V to 5.5V 1x, 2x and 3x Timing Chart and Device Operation When one or both of the EN pins are pulled high, the device enters normal operation mode, refer to the above table for the mode selection. Once the PAM8904 senses a valid signal on the DIN pin, the charge pump will start and provide the desired voltage on the VOUT pin and the output drive VO1 and VO2 start to function after time tON which is typically between 270µs and 350µs depending on the mode chosen. Once the input signal on DIN is removed, the PAM8904 senses this and waits typically 42ms to ensure the signal has been removed. If there is no further valid signal within the time period tOFF, the PAM8904 enters into a low current standby mode. Timing Chart tON tO FF
