Texas Instruments TPS65988EVM, User Manual

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The PDO LEDs in Table 5-4 are high, depending on which PDO is negotiated. By activating these LEDs, the
output voltage of the variable DC/DC can be changed. Table 5-4 summarizes the PDO LED behavior.
Table 5-4. PDO LED 0 and PDO LED 1 Truth Table
PDO PDO LED 1 PDO LED 0 R1 R2 Output Voltage
PDO 1 (5 V) 0 0 60.4 kΩ 19.1 kΩ 5.15 V
PDO 2 (9 V) 0 1 60.4 kΩ 9.27 kΩ 9.26 V
PDO 3 (15 V) 1 0 60.4 kΩ 5.2 kΩ 15.62 V
PDO 4 (20 V) 1 1 60.4 kΩ 4.04 kΩ 19.78 V
5.2.3 S2 Switch Bank Functionality
The I
2
C address setting must match the configuration generated by the TPS65988 configuration tool. Table 5-5
summarizes the I
2
C address settings. To adjust the dead battery boot behavior, the setting on ADCIN1 can be
adjusted. Table 5-6 summarizes the ADCIN1 settings. The specific settings for each divider ratio is discussed in
the TPS65988 datasheet .
Table 5-5. I
2
C Address Setting
Switch On, Off Bits Divider Ratio
1-3 Off 000b 0.00
1 On 001b 0.34
2 On 010b 0.50
3 On 011b 0.90
Table 5-6. ADCIN1 Setting
Switch On, Off Bits Divider Ratio
4-6 Off 000b 0.00
4 On 001b 0.34
5 On 010b 0.50
6 On 011b 0.90
Setup www.ti.com
28 TPS65988 Evaluation Module SLVUB62B – JUNE 2017 – REVISED NOVEMBER 2020
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