7

Protection features

TCPP02-M18 embeds protection features for source applications, as required by:

•

USB-C specification

•

USB power delivery specification 3.1

•

International electrotechnical commission (IEC)

7.1

FLGn pin description

FLGn pin is an open-drain output flag in steady state, it must be left floating when not connected.

In normal mode, FLGn indicates an error (OVP, OCP or OTP): I2C registers must be read to identify the error.

Recovery for each error type is described in each section of below paragraphs.

7.2

How to protect against ESD (electrostatic discharge) applied on the USB Type-

C™ connector?

Electrostatic discharges can be conducted by the USB Type-C™ connector and damage the electronic circuitry of

the application.

The international electrotechnical commission modelize the ESD surge waveform in the specification

IEC61000-4-2.

The TCPP02-M18 integrates ESD protection for CC1 and CC2 lines up to +8 kV contact discharge, associated

with an external 100 nF - 50 V capacitor on CBIAS pin.

Please refer to AN4871 USB Type-C™ protection and filtering to apply a required protection to comply with the

IEC61000-4-2 specification.

For more information on IEC61000-4-2 standard testing, please refer to the STMicroelectronics application note

AN3353.

7.3

VBUS management

Until now, it was common to find the protection circuit inside a controller dedicated to USB-C power delivery.

However, by supporting USB-C PD with an embedded module inside an MCU and a companion Type-C port

protection device, you can lower your bill of material and facilitate the transition , without requiring an expensive

USB-C PD ASIC controller. One of the reasons the MCU and TCPP02-M18 bundle is such a compelling financial

proposition is that the latter device integrates the VBUS gate drivers, which enables the use of cheaper and

smaller N-MOSFETs, instead of the P-MOSFETs usually used by ASIC controllers.

7.4

VBUS current sense (IANA pin)

The IANA output pin is active only in normal mode.

The IANA output can be connected directly to the STM32 ADC input because it is internally biased by EN pin.

The IANA output voltage level is about 1.7 V at the OCP tripping level allowing connection to 1.8 V MCU I/O pin.

TCPP02-M18

Protection features

DS13787 - Rev 4

page 12/27