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Wavecom GX64 Application Note

Manual is about: power Management

Summary of GX64

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    Gx64 application note power management reference: wi_dev_gx64_apn_007 version: 001 date: 2007/01/31.

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    Trademarks ®, wavecom ® , wismo ® , open at ® , wireless cpu ® , wireless microprocessor ® and certain other trademarks and logos appearing on this document, are filed or registered trademarks of wavecom s.A. In france or in other countries. All other company and/or product names mentioned may be fi...

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    Table of contents 1 introduction............................................................................................ 5 1.1 abbreviations ............................................................................................................ 5 1.2 notation...................................

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    3.7 vrtc and alarm ...................................................................................................... 22 3.7.1 using alarm as periodic power on ............................................................. 22 4 reference designs ......................................................

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    1 introduction this document describes how to apply power, control power states (on/off), and give other hints on how to optimise the wireless cpu implementation. 1.1 abbreviations abbreviation description csd circuit switched data cps charging power supply. Indicates the voltage and current limited...

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    1.2 notation the following symbols and admonition notation are used to draw the reader’s attention to notable or crucially-important information. Note draws the readers attention to pertinent, useful or interesting information tip provides advice, suggestions, guidance or recommendations which augme...

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    2 block diagrams 2.1 system power management block diagram the gr/gs64 wireless cpus have a number of signals in the system connector that affect the power state. The signals in figure 1 show the signals for all types and variants of the gr/gs64 family of wireless cpus. Table 1 below lists what feat...

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    Table 1: type / variant configuration gr64001 gr64002 gs64 feature type pin(s) pin(s) pin(s) vcc psi √ 1,3,5,7,9 √ 1,3,5,7,9 √ 2,4,6,8,10,12 chg_in psi/psc √ 11 √ 11 √ 13 vusb psi √ 49 √ 34 vref as input √ vref as output psi √ 34 34 √ 65 vrtc psi √ 25 √ 25 √ 31 alarm psc √ 50 √ 32 pon_h psc √ 21 on/...

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    Figure 2: gs64 power management block diagram 2.2.2 gr64001 this variant of gr64 only implements two psc-options, on/off and chg_in. Figure 3: gr64001 power management block diagram the “pm on/off sequence logic” block diagram can be found in figure 5. Gx64 application note this document is the sole...

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    2.2.3 gr64002 this variant of gr64 implements all four psc-options, on/off, pon_h, alarm and chg_in. Figure 4: gr64002 power management block diagram the “pm on/off sequence logic” block diagram can be found in figure 5. Gx64 application note this document is the sole and exclusive property of wavec...

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    3 implementation recommendations this section describes how to implement features related to the power management of the wireless cpus. 3.1 applying power on vcc main power is applied to vcc using gnd as reference. The source can be any of the following listed types: • li-ion battery (3.7v nominal) ...

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    3.2 power state control of the wireless cpu there are a maximum of six signals that affects the hw power state of the gr/gs64 family of wireless cpus; four hw and two sw: • on/off (hw, all wireless cpus) • chg_in (hw, all wireless cpus) • pon_h (hw, gs64 only) • alarm (hw, gs64 and gr64002 as extern...

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    The two sw power state control signals are not included in figure 5. This figure only shows the hw-signals. Figure 6: power management state diagram figure 6 shows the impact five of the six control signals, listed above, have on the power management status of the wireless cpu. The at*e2reset is des...

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    The signal should be held low for at least t low time for the wireless cpu to be able to detect and respond with a power hold signal (pwr_keep). The signal can be held low for an unspecified amount of time but it is not recommended since it prevents the wireless cpu from respond to any other power s...

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    3.2.4 alarm the alarm-signal can be both an internal and external signal for all wireless cpus except gr64001 where it is only an internal signal. Internal means that the rtc is capable of waking up the main processor as long as vcc is available. External means that the signal is provided in the sys...

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    3.2.5 at+cfun this at-command is used to change the power state of the wireless cpu. See the at-command manual for more details. 3.2.6 at*e2reset this at-command will de-register from network and do the normal shut-down sequence, but instead of powering down jump to the reset vector. See the at-comm...

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    The numbers given above are approximations. The real current levels might differ, but should most often be less than what is listed. 3.4 charging a cps should be connected to chg_in only if a single li-ion battery is used as main power supply. In any other configuration chg_in must be left open (not...

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    Figure 7: interface circuit implementation for gs64 the level translator type used in figure 7 can be either st2378e from st microelectronics, max3001e from maxim, or any other applicable type. Figure 7 shows a gs64 implementation, but the same figure can be used for a gr64001 solution if the 1.8v r...

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    Figure 8: typical vref level translation implementation in a gr64002 one drawback of this solution is that vref cannot be used by the application to determine whether the wireless cpu is powered on or not. See 3.6.2 below for more information. 3.6 monitor “power on” state the power state of the wire...

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    3.6.2 gr64002 hw-detection in gr64002, where vref is an input to the wireless cpu the hw-detection of the power state must use simdet instead of vref. The simdet-signal is pulled up inside the wireless cpu to its internal supply voltage (1.8v). It does not go through the built-in level translators a...

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    Table 4: power state transition levels wireless cpu power status simdet level power on >1.5v power off it is possible to connect the simdet-signal directly to the application processor, but the integrator must ensure that no voltage is applied onto simdet (through pull-up resistors etc.). The wirele...

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    3.7 vrtc and alarm these are the two system connector signals that relate to the rtc. Vrtc is powered from vcc. If the application wants the rtc to operate even if vcc is removed it has to add a 1.5v “button cell” or capacitor on vrtc as a backup power source. A recommended battery to use is 0.2mah ...

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    The power supply should be an efficient converter that takes the v in supply from whatever voltage level the source is providing and converts it to the recommended vcc voltage level. To minimise power consumption this regulator is only enabled when the wireless cpu is supposed to be active. After th...

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    4 4.1 avecom inc is not responsible for the charger power supplies reference design. The integrator sho listed below d 4.2 dc/dc power supply he implementation shown in appendix a is the reference design of a 3.6v dc/dc buck regulator from national semiconductors. The input voltage can be between 6v...

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    4.3 ac/dc power supply the implementation shown in appendix b is the reference design of a 3.6v ac/dc tor from national semiconductors. The input voltage can be between 4.3.1 specifications flyback regula 85vac to 265vac. For more information on the design please contact national semiconductors. Par...

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    The circuit attains a periodic steady-state in which the volt-seconds across the are exactly balanced by the volt-seconds due to t voltage level transformer due to the input voltage the output voltage. For continuous conduction operation (in which the rectifier current never falls to zero), the outp...

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    Gx64 application note power management page: 27/30 4.3.3 bill of material ce document est la propriété exclusive de wavecom. Il ne peut être communiqué ou divulgué à des tiers sans son autorisation préalable this document is the sole and exclusive property of wavecom. Not to be distributed or divulg...

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    Gx64 application note power management page: 28/30 appendix a this document is the sole and exclusive property of wavecom. Not to be distributed or divulged without prior written agreement. Ce document est la propriété exclusive de wavecom. Il ne peut être communiqué ou divulgué à des tiers sans son...

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    This document is the sole and exclusive property of wavecom. Not to be distributed or divulged without prior written agreement. Ce document est la propriété exclusive de wavecom. Il ne peut être communiqué ou divulgué à des tiers sans son autorisation préalable gx64 application note power management...

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