ZHCSG04F january 2017 – may 2023 TPS65235-1
PRODUCTION DATA
The TPS65235-1 device has an internal compensated boost converter and low-dropout (LDO) linear regulator. The boost converter tracks the LNB output voltage within 800 mV even at loading 1000 mA, which minimizes power loss.
The boost converter operates at 1 MHz by default. The TPS65235-1 device has internal cycle-by-cycle peak current limit in the boost converter and DC current limit in the LNB output to help protect the device from short circuits and over loading. When the LNB output is shorted to ground, the LNB output current is clamped at the LDO current limit. The LDO current limit is set by the external resistor at the ISET pin. The current limit of the boost switch is proportional to the LDO current limit. If an overcurrent condition occurs for more than 4 ms, the boost converter enters hiccup mode and retries startup in 128 ms. This hiccup mode ON time and OFF time are selectable through the I2C control register (address 0x01) to be either 4 ms and 128 ms or 8 ms and 256 ms, respectively. At extremely light loads, the boost converter automatically operates in a pulse-skipping mode.
The boost converter is stable with either ceramic capacitor or electrolytic capacitor.
If two or more set-top box LNB outputs are connected together, one output voltage can be set higher than others. The output with the lower set voltage is then effectively turned off. When the voltage drops to the set level, the LNB output with the lower set output voltage returns to normal conditions.