1. Overview

The TPM-Click board provides a TCG-standardised platform expanding trust from personal computing to connected devices. This board features the STMicroelectronics ST33KTPM2X, a STSAFE-TPM trusted platform module 2.0.

The STSAFE-TPM is a secure element product range providing authentication, confidentiality and platform integrity services to protect OEMs against cloning, counterfeiting, malware injection and unauthorised production. The STSAFE-TPM includes turnkey products compliant with the Trusted Computing Group (TCG) standards that provide services to protect the confidentiality, integrity and authenticity of information and devices. The STSAFE-TPM devices are all Common Criteria (EAL4+) and FIPS certified.

The ST33KTPM2X device is a member of the ST STSAFE-TPM (trusted platform module) family of products, which offers a broad portfolio of standardised solutions for embedded, PC, mobile and computing applications. The ST33KTPM2X is a TPM 2.0-compliant device, that is easy to integrate in an embedded design, using the standards-compliant SPI and I2C interfaces to the host SoC, such as the ST STM32MP1.

2. TPM-Click Module

The TPM-Click module is fully compatible with the Click / mikroBUS protocol. The only exception is use of the +5V power supply, which is not supported by the TPM-Click.

The default configuration of the TPM-Click module is to use the I²C Bus for communications with the host. The speed of the I²C Bus speed is limited 1MHz. If a higher throughput is required, then the SPI bus can be chosen. To select the SPI, the following parts must be populated: on the TPM-Click module:

• R3-R6 soldered on

• C1 soldered on

• JP1 closed.

The following picture shows the TPM-Click module, in the default hardware configuration:

Open

3. Hardware Specification

3.1. High-Level Specification

The following are the key characteristics of the TPM-Click module:

3.2. Electrical Specification

The following is the electrical specification of the TPM-Click module:

3.3. Pin-out

The following table shows how the pin-out on the TPM-Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin	Open				Pin	Notes
	NC	1	AN	PWM	16	PP	Physical Presence, active high, internal pull-down. Used to indicate Physical Presence to the TPM.
Reset	nRST	2	RST	INT	15	nIRQ	TPM interrupt request to the host, active low
NC by default, optional SPI Chip (or Slave) Select	CS	3	CS	RX	14	NC
NC by default, optional SPI Serial Clock	SCK	4	SCK	TX	13	NC
NC by default, optional SPI Master Input, Slave Output	MISO	5	MISO	SCL	12	SCL	I2C Clock
NC by default, optional SPI Master Output, Slave Input	MOSI	6	MOSI	SDA	11	SDA	I2C Data
Power Supply	3.3V	7	3.3V	5V	10	NC
Ground	GND	8	GND	GND	9	GND	Ground

3.4. On-board Jumpers

The following are the user-selectable on-board settings of the TPM-Click module:

4.  References

1. DB5174 STSAFE-TPM trusted platform module 2.0 with a SPI or I²C interface https://www.st.com/resource/en/data_brief/st33ktpm2x.pdf

2. ST33KTPM2X - STMicroelectronics