Datasheet

HUSB238A

©2023 Hynetek Semiconductor Co., Ltd. All rights reserved.

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THEORY OF OPERATION

The HUSB238A is a USB PD Sink controller. It supports PD protocol and legacy charging protocols detection and

requests the desired power per the user settings. The HUSB238A can run in I2C mode and GPIO mode. In I2C mode,

an I2C master can access the HUSB238A to configure settings, read back status and perform advanced functions such

as DR Swap, VDM messages. While in GPIO mode, the configuration is achieved via the setting pins.

POR AND UVLO

HUSB238A can be powered by VDD pin or VBUS pin. The VDD pin has higher priority. When the voltage at VDD pin

exceeds the VDD_UVLO_R or the VBUS voltage exceeds the VBUS_UVLO_R when VDD < VDD_UVLO_F, HUSB238A starts

initialization.

When the voltage at VDD pin is less than VDD_UVLO_F and VBUS voltage is less than VBUS_UVLO_F, the HUSB238A is reset.

ENABLE CONTROL

HUSB238A has an enable pin (EN_N) for the whole system control. When EN_N is high, the whole system is disabled,

When EN_N is low, the whole system is enabled.

When EN_N is low, and HUSB238A is in I2C mode, there is an additional ENABLE bit (Register CONTROL1[3]) to

enable or disable the HUSB238A, when this ENABLE bit is 0b, all of functions of HUSB238A is turned off except the

I2C accessibility, EN_N detection and UVLO detection. Only when the ENABLE=1b, the disabled functions resume to

work.

ADDR/ORIENT PIN

For ADDR/ORIENT pin, it is employed to select whether HUSB238A works as I2C mode or GPIO mode.

Table 6. Work Mode Configuration

ADDR/ORIENT Connection

HUSB238A Work Mode Configured

Connected to VDD via a 900kΩ Resistor

I2C mode with slave address=62H

Floating

GPIO mode

Connected to GND via a 900kΩ Resistor

I2C mode with slave address=42H

EN_HVDCP/OUT1 PIN

For EN_HVDCP/OUT1 pin, it is employed to determine whether HUSB238A can support HVDCP detection.

Table 7. Legacy Protocol Detection Configuration

EN_HVDCP/OUT1 Connection

HUSB238A Legacy Protocol Detection

Connected to VDD via a 900kΩ Resistor

Perform BC1.2 and HVDCP protocols

Floating

Perform BC1.2 and HVDCP protocols

Connected to GND via a 900kΩ Resistor

Only perform BC1.2 detection

VBUS PIN

The VBUS pin has multiple functions for the applications. It could be an input power source for the IPR, the discharging

path and the monitor pin for protections and disconnection.

VOLTAGE MEASUREMENT

A ADC is connected to the VBUS pin as well, the VBUS voltage is updated periodically in the VBUS MEASUREMENT

register. The I2C master can read this register to make further decision.

ANALOG INPUT PINS

After the initialization, the HUSB238A is able to output the status of current connection. When ADDR/ORIENT is floating

during initialization, HUSB238A is in GPIO mode. In this mode, the SDA/SNK_VSET, SCL/SNK_ISET pins are

repopulated as analog input pins.

SNK_VSET PIN

This pin is used to set the request voltage. This pin is pulled up internally. Connect a resister with 1% tolerance between

SNK_VSET and GND to indicate the SNK_VSET_VOLTAGE value as shown in Table 8.