Method and apparatus for rapidly and dynamically adjusting current limiting in a portable communication device

• US 10,470,062 B1
• Filed: 03/12/2019
• Issued: 11/05/2019
• Est. Priority Date: 07/30/2018
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola Solutions, Inc.
• Inventors: Bartels, Peter J., Alfaro, Javier, Cutcher, Jeffrey L., Alonso, Kevin, Glass, Stephen C.
• Primary Examiner(s): Le, Lana N
• Application Number:
  US16/299,647
• Time in Patent Office: 238 Days
• Field of Search: None
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06F 1/28 Supervision thereof, e.g. detecting power-supply failure by out of limits supervision
• CPC Class Codes: G06F 1/30 Means for acting in the event of power-supply failure or interruption, e.g. power-supply fluctuations for resetting only G06F1/24
• CPC Class Codes: G06F 1/3206 Monitoring of events, devices or parameters that trigger a change in power modality
• CPC Class Codes: G06F 1/3212 Monitoring battery levels, e.g. power saving mode being initiated when battery voltage goes below a certain level
• CPC Class Codes: G06F 1/3234 Power saving characterised by the action undertaken
• CPC Class Codes: G06F 1/3293 by switching to a less power-consuming processor, e.g. sub-CPU
• CPC Class Codes: H02J 7/00304 Overcurrent protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: H02J 7/0063 with circuits adapted for supplying loads from the battery
• CPC Class Codes: H02J 7/0071 with a programmable schedule
• CPC Class Codes: H03F 2200/03 the amplifier being designed for audio applications
• CPC Class Codes: H03F 2200/451 the amplifier being a radio frequency amplifier
• CPC Class Codes: H03F 3/183 with semiconductor devices only
• CPC Class Codes: H03F 3/19 with semiconductor devices only
• CPC Class Codes: H03F 3/245 with semiconductor devices only
• CPC Class Codes: H04W 24/04 Arrangements for maintaining operational condition
• CPC Class Codes: H04W 4/10 Push-to-Talk [PTT] or Push-On-Call services
• CPC Class Codes: H04W 52/00 Power management, e.g. TPC [Transmission Power Control], power saving or power classes gain control in transmitters or power amplifiers H03G3/3042
• CPC Class Codes: H04W 88/02 : Terminal devices
• CPC Class Codes: Y02D 10/00 : Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

A battery operated portable communication device provides converged functionality while avoiding resets to the device. Composite logic circuitry formed of at least one comparator and a logic interface controls current limiting to a primary load formed of high power land mobile radio (LMR) devices and programming to secondary loads formed of non-LMR peripherals. At least one current limit control signal is used to control current to the primary load under high current mode operations. Another control signal provides an interruption alert to a slave processor for controlled programming of the secondary loads during the high current operations of the primary load. Current to the primary load is restored while the secondary load is interrupted. Operation of secondary load processes is resumed when the primary load ceases high power operation.

Claims

1. A portable communication device, comprising:

a battery having battery profile;

a master processor for controlling a primary load providing mission critical land mobile radio (LMR) radio operations;

a slave processor for controlling a secondary load of non-LMR processes, the LMR operations and non-LMR processes operating in parallel;

a comparator bank coupled to the master processor and the battery, the comparator bank being configured with a plurality of trip thresholds based on the battery profile, the comparator bank monitoring the battery for a predetermined high current LMR radio condition;

a logic interface coupled to the comparator bank, the logic interface generating a current limit control signal and an interrupt control signal in response to the comparator bank detecting the predetermined high current LMR radio condition at a primary load, the current limit control signal being applied to a current limiter selection stage, and the interrupt control signal being applied to the slave processor; and

the current limiter selection stage providing scaled back current to the primary load in response to the current limit control signal indicating the predetermined high current LMR radio condition, the slave processor scaling down maximum allowable clock rates of non-LMR peripherals in response to the interrupt control signal, the current limiter selection stage restoring maximum current to the LMR operations of the primary load in response to the slave processor scaling down core clock rates of non-LMR peripherals at the secondary load, the non-LMR processes being restored after the predetermined high current LMR radio condition ceases, thereby enabling parallel operation of LMR radio operations and non-LMR radio processes to resume.

2. The portable communication device of claim 1, wherein the comparator bank comprises a programmable comparator bank having a plurality of comparators controlled by the master processor to trip at predetermined and progressively lower battery voltage thresholds, thereby controlling attenuation of the primary and secondary loads.

3. The portable communication device of claim 1, wherein the current limiter selection stage comprises a switched resistive network for scaling current to the primary load.

4. The portable communication device of claim 1, wherein the current limiter selection stage comprises a switched resistive network for scaling current to the primary load.

5. The portable communication device of claim 1, wherein the primary load comprises at least:

a LMR RFPA; and

an audio PA.

6. The portable communication device of claim 5, wherein the secondary load comprises at least one of:

a long term evolutions (LTE) feature;

a WiFi feature; and

a GPS feature.

7. The portable communication device of claim 1, wherein the current limiter selection stage comprises a switched resistive network for scaling current to the primary load.