ST25DV04K datasheet(7/197 Pages) STMICROELECTRONICS

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2.3

RF link (AC0 AC1)

2.3.1

Antenna coil (AC0, AC1)

These inputs are used to connect the ST25DVxxx device exclusively to an external coil. Do not connect any other

DC or AC path to AC0 or AC1.

When correctly tuned, the coil is used to power and access the device using the ISO/IEC 15693 and ISO 18000-3

mode 1 protocols.

2.4

Process control (VDCG, GPO)

2.4.1

Driver supply voltage (VDCG)

This pin, available only with ST25DVxx-JF version, can be connected to an external DC supply voltage. It

supplies only the GPO driver block, not the whole device. If VDCG is left floating, no information is available on the

GPO pin.

2.4.2

General purpose output (GPO)

The ST25DVxxx feature a configurable output GPO pin used to provide RF activity information to an external

device. ST25DVxx-IE offers a GPO open drain. This GPO pin must be connected to an external pull-up resistor

(> 4.7 kΩ) to operate.

The interrupt consists in pulling the state to a low level, or outputting a low level pulse on the GPO pin.

ST25DVxx-JF offers a GPO CMOS output, which requires to connect VDCG pin to an external power supply. The

interrupt consists in setting the state to a high level or outputting a positive pulse on the GPO pin.

GPO pin is a configurable output signal, and can mix several Interruption modes. By default, the GPO register

sets the interruption mode as an RF field change detector. It is able to raise various events like RF activity,

memory write completion, or fast transfer actions. It can authorize the RF side to directly drive GPO pin using the

Manage GPO command to set the output state or emit a single pulse (for example, to wake up an application.).

See Section 5.2 GPO for details.

2.5

Energy harvesting analog output (V_EH)

This analog output pin is used to deliver the analog voltage V_EH available when the Energy harvesting mode

is enabled, if the RF field strength is sufficient. When the Energy harvesting mode is disabled, or the RF field

strength is not sufficient, V_EH pin is in high-Z state (see Section 5.3 Energy harvesting (EH) for details).

Energy harvesting voltage output is not regulated.

ST25DV04K ST25DV16K ST25DV64K

RF link (AC0 AC1)

DS10925 - Rev 11

page 7/197

ST25DV04K Datasheet(PDF) 7 Page - STMicroelectronics