US-12620804-B2 - Power management in a near field communication controller

US12620804B2US 12620804 B2US12620804 B2US 12620804B2US-12620804-B2

Abstract

A near field communication controller integrated circuit includes a power management circuit configured to retransmit an external supply voltage from at least one power supply input node to at least one power supply output node in a bypass power supply mode. The power management circuit is hardware configured to automatically enable the bypass power supply mode in response to the external supply voltage being present at the at least one power supply input node.

Inventors

Patrick Arnould

Assignees

STMicroelectronics (Alps) SAS

Dates

Publication Date: 20260505
Application Date: 20231020
Priority Date: 20221024

Claims (20)

1 . An integrated circuit, comprising: a near field communication controller including a power management circuit configured to: retransmit an external supply voltage from a power supply input node to a power supply output node in a bypass power supply mode, and automatically enable the bypass power supply mode in response to the external supply voltage being present at the power supply input node, wherein the power management circuit comprises: a configuration register storing configuration data to enable or disable automatic enabling of the bypass power supply mode, a logic circuit configured to automatically enable the bypass power supply mode based on the presence of external supply voltage and the configuration data stored in the configuration register, and a slew rate limiter configured to limit a rate of current change at the power supply output node, the power management circuit configured to control a start-up of the slew rate limiter in the bypass power supply mode.
2 . The integrated circuit according to claim 1 , wherein the power management circuit includes a voltage detection circuit configured to detect the presence of the external supply voltage at the power supply input node.
3 . The integrated circuit according to claim 1 , wherein the power management circuit is configured to operate independently and automatically in a low power mode of the near field communication controller.
4 . The integrated circuit according to claim 1 , wherein the power management circuit further includes a voltage generator configured to generate an internal supply voltage at the power supply output node, in an autonomous power supply mode.
5 . The integrated circuit according to claim 4 , wherein the power management circuit includes a switch circuit having a first input configured to receive the external supply voltage, and a second input configured to receive the internal supply voltage, the switch circuit configured to: selectively provide the external supply voltage to the power supply output node, in the bypass power supply mode; and selectively provide the internal supply voltage to the power supply output node, in the autonomous power supply mode.
6 . The integrated circuit according to claim 4 , wherein the internal supply voltage is regulated at a level configured to power an external peripheral device.
7 . The integrated circuit according to claim 1 , wherein the integrated circuit is couplable to a security peripheral device that is powered on by a voltage at the power supply output node of the near field communication controller.
8 . The integrated circuit according to claim 1 , wherein the integrated circuit is couplable to a telecommunications control circuit that provides the external supply voltage to the power supply input node of the near field communication controller.
9 . A system, comprising: a near field communication controller integrated circuit, the near field communication controller integrated circuit including a power management circuit configured to: retransmit an external supply voltage from a power supply input node to a power supply output node in a bypass power supply mode, and automatically enable the bypass power supply mode in response to the external supply voltage being present at the power supply input node; a telecommunications control circuit configured to provide the external supply voltage to the power supply input node of the near field communication controller; and a security peripheral device configured to be powered on by a voltage at the power supply output node of the near field communication controller, wherein the power management circuit includes: a configuration register storing configuration data to enable or disable automatic enabling of the bypass power supply mode, a logic circuit configured to automatically enable the bypass power supply mode based on the presence of external supply voltage and the configuration data stored in the configuration register, and a slew rate limiter configured to limit a rate of current change at the power supply output node, the power management circuit configured to control a start-up of the slew rate limiter in the bypass power supply mode.
10 . The system according to claim 9 , wherein the power management circuit includes a low dropout regulator voltage generator configured to generate an internal supply voltage at the power supply output node in an autonomous power supply mode, the internal supply voltage being regulated to a level configured to power an external peripheral device.
11 . The system according to claim 10 , wherein the power management circuit includes a switch circuit having a first input configured to receive the external supply voltage, and a second input configured to receive the internal supply voltage, the switch circuit configured to: selectively provide the external supply voltage to the power supply output node, in the bypass power supply mode; and selectively provide the internal supply voltage to the power supply output node, in the autonomous power supply mode.
12 . The system according to claim 9 , wherein the power management circuit includes a voltage detection circuit configured to detect the presence of the external supply voltage at the power supply input node.
13 . The system according to claim 9 , wherein the power management circuit is configured to operate independently and automatically in a low power mode of the near field communication controller.
14 . A method, comprising: retransmitting, by a power management circuit of a near field communication controller integrated circuit, an external supply voltage from a power supply input node to a power supply output node in a bypass power supply mode; and automatically enabling the bypass power supply mode, by the power management circuit, in response to the external supply voltage being present at the power supply input node wherein the automatically enabling the bypass power supply mode includes: automatically enabling the bypass power supply mode, by a logic circuit of the power management circuit, based on the presence of the external supply voltage at the power supply input node, and based on configuration data stored in a configuration register of the power management circuit, and limiting, by a slew rate limiter, a rate of current change at the power supply output node, a start-up of the slew rate limiter controlled by the power management circuit in the bypass power supply mode.
15 . The method according to claim 14 , comprising detecting the presence of the external supply voltage at the power supply input node, by a voltage detection circuit of the power management circuit.
16 . The method according to claim 14 , wherein the method is implemented independently and automatically in a low power mode of the near field communication controller.
17 . The method according to claim 14 , further comprising generating an internal supply voltage at the power supply output node in an autonomous power supply mode.
18 . The method according to claim 17 , wherein the power management circuit includes a switch circuit having a first input for receiving the external supply voltage, and a second input for receiving the internal supply voltage, the method further comprising: selectively providing, by the switch circuit, the external supply voltage to the power supply output node, in the bypass power supply mode; and selectively providing, by the switch circuit, the internal supply voltage to the power supply output node, in the autonomous power supply mode.
19 . The method according to claim 14 , further comprising: providing the external supply voltage to the power supply input node by a telecommunications control circuit; and powering on a security peripheral device by the near field communication controller by a voltage at the power supply output node.
20 . The method according to claim 14 , further comprising powering a security peripheral device by a voltage at the power supply output node of the near field communication controller.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of French Patent Application No. 2210986, filed on Oct. 24, 2022, which application is hereby incorporated herein by reference. TECHNICAL FIELD Embodiments and implementations relate to the management of the power supply in a near field communication (NFC) controller. Embodiments and implementations relate in particular to the management of the power supply of the security peripherals that may be used by the NFC controller and also by another telecommunications control device. BACKGROUND Near field communication (NFC) makes a contactless communication possible over a short distance, for example 10 cm, between a reader and a transponder, by modulation and back-modulation of the amplitude of a carrier wave at 13.56 MHz. NFC technology is an open technology platform, standardized in particular in the standard ISO-14443. NFC communications may be implemented between two peer-to-peer communication devices, such as multifunction telephones (usually referred to as “smartphone”); or also between a reader device and a transponder device, such as a RFID or NFC or tag or card or a multifunction telephone in card-emulation mode. Security peripherals, for example Subscriber Identification Modules (SIM), provide a security service typically shared between various applications, particularly NFC communications and other telecommunications, for example of the Long Term Evolution (LTE) type telephony or data rate particularly incorporating the 4th generation (4G) and 5th generation (5G) telephony standards or others. On the one hand, for example when the telephone emulates a card mode, the security peripherals may also be used by the NFC controller for NFC applications (for example, travel card, travel document, etc.) even if the telephone is switched off or in a mode where the telecommunications functionalities are disabled (usually called “airplane mode” for example). On the other hand, reciprocally, if the NFC controller is disabled, for example in an energy saving mode or forced to an off state, the security peripherals may be used for the other telecommunications (for example the telephony). The fact of providing these two functionalities typically presents difficulties in the management of the power supply of the security peripherals. In particular, when the management of the power supply of the security peripherals is implemented by the NFC controller, the use of the security peripherals conventionally leads to a “wake-up” of the NFC controller by interruption signals, that is to say an exit from the energy saving mode, to establish the power supply of the peripherals by software commands, then a return to the energy saving mode. The boot processes during wake-ups of the NFC controller lead to unnecessary energy consumptions and possibly also a latency before the effective establishment of the power supply of the peripherals. Moreover, if the NFC controller is forced in the off state, the wake-up of the controller for managing the power supply of the peripherals is conventionally impossible. Consequently, the conventional NFC controllers implementing the management of the power supply of the peripherals may not benefit from the functionality of being forced in the off state. SUMMARY In various embodiments, the present disclosure provides a hardware configuration of a NFC controller that at least partially overcomes the drawbacks of conventional NFC controllers, for example, by performing the management of the power supply of the peripherals, automatically and independently of the operating mode of the controller. Particular embodiments and implementations provide a power supply of the peripherals by an external supply voltage provided in bypass by the NFC controller. In at least one embodiment, an integrated circuit is provided that includes a near field communication controller including a power management circuit configured to retransmit an external supply voltage from at least one power supply input node to at least one power supply output node in a bypass power supply mode. The power management circuit is hardware configured to automatically enable the bypass power supply mode in response to the external supply voltage being present at the at least one power supply input node. “Hardware configured” means that the circuit is manufactured to implement the corresponding function, and in particular, that the corresponding function is not from a software execution of a program. According to at least one embodiment, the power management circuit includes at least one voltage detection circuit hardware configured to detect the presence of the external supply voltage at the at least one power supply input node. According to at least one embodiment, the power management circuit includes a logic circuit hardware configured to automatically enable the bypass power supply mode, based on the presence of the external supply voltage, and based on at least