ZHCSE79C March 2011 – September 2015
PRODUCTION DATA.
Protection diodes limit the voltage compliance at terminal H, terminal L, and terminal W, making it important to power up VDD first before applying any voltage to terminal H, terminal L, and terminal W. The diodes are forward-biasing, meaning VDD can be powered unintentionally if VDD is not powered first. The ideal power-up sequence is VSS, VDD, VLOGIC, digital inputs, and VH, VL, and VW. The order of powering digital inputs, VH, VL, and VW does not matter as long as they are powered after VSS, VDD, and VLOGIC.
It is prudent to know that when the DPOT is powered off, the impedance of the device is not known. Upon power up, the device will go to 0x80h code for a very short period of time while it loads the stored wiper position in the EEPROM and then will go to the stored position. This happens in less than 100 uS.
Dual-supply operation allows the TPL0102 to handle voltage that may swing negative. This is especially useful for any application that involves negative voltages, such as the input to an Op Amp or audio signals. It is recommended that VSS (negative supply) is mirrored with VDD (positive supply) and both are centered around GND. For example, if dual-supply is desired and VDD = 2.50 V, then VSS should be equal to -2.50 V, which will result in GND centered between VDD and VSS.
Single-supply operation allows the TPL0102 to handle positive voltages only. In single-supply, it is recommended that VSS is tied to GND.