9.5.1 Addressable Registers

Three registers with a data content of five bits are addressable. With 5-bit data content, 32 different values for each register are available. Table 1 shows the addressable registers to set the output voltage when the DEF_1 pin works as a digital input. In this case, converter 1 has a related register for each DEF_1 pin condition, and one register for converter 2. A high or low condition on pin DEF_1 (TPS62402-Q1, TPS62404-Q1, and
TPS62405-Q1) selects either the content of register REG_DEF_1_High or REG_DEF_1_Low, thus setting the output voltage of converter 1 according to the values in Table 4.

Table 2 shows the addressable registers if the DEF_1 pin acts as an analog input with external resistors connected. In this case, one register is available for each converter. The values in Table 5 set the output voltage of converter 1. Table 6 shows the available voltages for converter 2. Use of a precise internal resistor divider network to generate these output voltages makes external resistors unnecessary (less board space) and provides higher output-voltage accuracy. Enabling at least one of the converters (EN1 or EN2 is high) activates the interface. After the start-up time t_Start (170 μs), the interface is ready for data reception.