STS1TX datasheet(33/70 Pages) STMICROELECTRONICS

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STS1TX

Block description

Figure 6. Shaping of ASK signal

8.8

Temperature sensors (TS)

The STS1TX can provide an analog temperature indication as a voltage level, which is

available at the GPIO_0 pin. The voltage level V0 at room temperature (or any other useful

reference temperature) should be acquired and stored by the MCU in order to compensate

for the offset. The relationship between temperature and voltage is the following:

Equation 1

where V0 is the voltage at temperature T0.

Two output modes are available: buffered or not buffered (high output impedance, about

100 k

Ω). The latter mode is the default.

The TS function is available in every operating mode. When enabled, the internal logic

allows the switching on of all the necessary circuitry.

To enable the TS function, the user must perform the following operations:

•

Set to 1 the TS bit in the ANA_FUNC_CONF[0] register

•

Program as “Analog” (00) the GPIO_MODE field in the GPIO0_CONF register (other

fields are neglected)

•

Optionally, enable the buffered mode (the EN_TS_BUFFER bit in the PM_CONFIG[2]

As the TS function requires the internal bias circuit operation, the overall current

consumption in STANDBY, SLEEP, and READY modes is increased by 400 µA.

8.9

AES encryption co-processor

The STS1TX provides data security support as it embeds an advanced encryption standard

(AES) core which implements a cryptographic algorithm in compliance with NIST FIPS 197.

T400

Vtemp V0

–

()

T0 3.75

()

⋅

°C

()

STS1TX Scheda tecnica(PDF) 33 Page - STMicroelectronics