Measuring how the voltage (energy) and the control voltage

 Measuring how the voltage (energy) and the control voltage

    What is Active measurement?
    Measurements were made when the phone has been awarded the supply voltage. Voltage into the energy management is channeled to the active component is necessary, only the active component has a need for some tension so that the active component can work, in the interests of active measurement is required, in order to measure the stress of work required by a specific active component whether it is consistent with what required or not? If the value required in accordance with certain values, then certainly there is a problem on the main active component, but if the stress does not correspond to the required value of the damage ascertained from the components that provide this voltage, energy management or the LDO regulator.
  
What is the active component?
    Each active component contained in a circuit can work if there is energy that comes to him, basically given by the energy source Battrey. All active components of the voltage supplied by energy source, because the energy needs of each different active components, in terms of consumption needs of voltage, current, and even phase voltage requirements, energy management is needed. Energy management is an active component - commonly called the IC power - energy supplied by batteries. Furthermore, the energy is distributed to other active components in accordance with the needs of the component.
    Apart from energy management at the top, there are also other components of the same function. But it serves to assist in workload management to distribute energy stress. This component is usually called LDO (Low Drop Out) regulator, SMPS (Switch Mode Power Supply).
    Voltage measurement rules (Energy) and the control voltage!
    Active measurements can be made when the battery voltage has been entered into the management of energy and then distributed to other active components. Certain stages of distribution process, so that when the battery (VBATT) supply voltage on energy management and LDO regulators, voltage output is not necessarily spread to the component that requires, at least this distribution requires voltage control (command / enable) to set when a voltage is applied and when the voltage is not provided.
    Based on research conducted distribui stage in the process of working voltage mobile machine there are three conditions or phases, namely:

    1. Step 1: Tensions will come out when power is pressed, without waiting for status mobile life or not;

    1. Step 2: Stress-specific voltage will come out only when the CPU gives orders

    for distributors of components for relieving stress is the stress;

    1. Step 3: Stress-specific voltage will be out within the system worked RF

 
  
    Example 1: how to measure vCore voltage
    In the picture above, there vCore voltage to the voltage step-1 group (green columns). VCore voltage on the picture will appear at the reset position and so on, which means that the activity re-start until the phone is active then exit with vCore voltage stabilized at the value of 1.4V. in this condition we can take measurements. Therefore for certain if the power is on is not pressed, then the VCore voltage can not be measured.
     
Example 2: How to measure voltage VCAM (Camera)
    In the picture above, there VCAM voltage stress on the second step (yellow column). VCAM voltage will come out when camera is active. Even if the phone is in active / live VCAM no stress, he came out when there is a command from the CPU to the LDO voltage regulator to issue to the camera. This command appears when the camera is activated.
    Especially in the measurement step 2, note the voltage will be disconnected (disabled) by the CPU when the external components (camera, MMC) in a condition not working properly. Therefore we can not perform measurements using an AVO meter voltage range for the camera and MMC, although LDO work. This is caused by the duration of the stress that comes out of the LDO is very short even counted in seconds. Measurements can only be done by using an oscilloscope
     
Example 3: Rules to measure the voltage on the RF module series
    Voltage in step 3 consists of: VCP1,, VCP2 VReg1, VReg2, VR1_RX, VOut_RX. All the stress will just get out while the RF system is activated. RF system on the phone will be active when the operator manually search process conditions, or conditions that make the call. This situation is not related to the presence or absence of signal on the phone. Therefore, measurements can only be done when the system is active RF.
     
Measure the voltage control rules
    Active measurements above shows the action for voltage measurement. It can also be performed to measure voltage or voltage control command. The voltage stress is not as energy for various mobile phones, but this voltage is used as a control (enable / disable) on the circuit. It's like a command to the circuit voltage at a given command. PURX commands for the voltage, the voltage that is provided by retu to RAP. This voltage is the command to reset the voltage of the RAP. Another example of the voltage command on the Nokia BB5 RSTX. This voltage is given by retu to TAHVO, so the work TAHVO.

    good luck