ADF7030-1 - FAQ
How do I calculate the total power consumption of my system?
The total power consumption of the radio system depends on multiple factors described below. The power consumption should be measured or simulated for each of these states to understand the expected battery life.
For systems which wake frequently to transmit or receive a packet, the total power consumption of the system will likely be dominated by active power consumption and state transition times. For systems which spend longer durations inactive, the power consumption will be dominated by the sleep mode power consumption.
- Active mode power consumption: This is the current consumed in the active receive and transmit states of the radio
- Sleep mode power consumption: This is the current consumed when the radio is in sleep mode with memory retained. In this state, the radio can be woken up relatively quickly without the need for the microcontroller to fully re-program it. At 10nA, the ADF7030-1 is industry leading in this mode
- Shutdown power consumption: In this mode power is removed from the device and the total power consumption consists of leakage current and battery self-discharge only
- State Transition timing: This is the power consumed as the device is changing state
- Battery Self-Discharge: This will be defined by the battery manufacturer and should be considered as part of the calculation for total system consumption
What is Smart Wake Mode?
Smart Wake Mode allows the ADF7030-1 to wake up autonomously from sleep using the internal wake-up timer without intervention from the host processor. After wake-up, the ADF7030-1 can autonomously carrier sense, packet sniff, and receive packets while the host processor is in sleep, thereby reducing overall system current consumption. The smart wake mode can wake the host processor on an interrupt condition. These interrupt conditions can be configured to include the reception of valid preamble, sync word, CRC, or address match.
What range can I achieve with this part?
The range that can be achieved will depend on the below variables:
- Carrier Frequency: The lower the frequency, the further the signal will travel in free space according to the below Free Space Path Loss equation where f is in MHz and d is in meters. This equation describes the reduction in effective power of an RF signal as it travels through free space.
- Data Rate: With lower data rates, receiver sensitivity is improved. Therefore as the data rate is lowered, the range will increase. Variations in data rates can have a significant effect on sensitivity. On the ADF7030-1, a signal at 100bps can be received at -134dBm. Compare this with a signal at 100kbps where the signal must be at -107dBm to be received.
- Antenna: The antenna design affects both sides of the link budget – both on the transmit power and receive sensitivity. Higher gain antennas will enable greater range. Antenna designs will vary depending on the application form factor and environment. Antenna sizes vary with the carrier frequency. As frequency is increased, similar antenna gain performance can be achieved with a physically smaller antenna. Users are recommended consult antenna design specialists to optimize the antenna for their product.
- Building type: For wireless systems deployed within buildings, the achievable range will vary depending on wall thickness, materials used and other structural factors. In general, lower frequencies will have greater penetration through structures compared to higher frequencies.
Where can I access the full bundle of support collateral?
The ADF7030-1 Design Package is a complete documentation and resource package for the ADF7030-1. It is recommended to download this package as a starting point for evaluation and development. It contains manuals, application notes, hardware information, software drivers and firmware modules. It can be downloaded from the Analog Devices website.
Can I run my own code on the Cortex M0 on the ADF7030-1?
Users cannot run custom code on the Cortex M0 on the ADF7030-1. However, ADI will release firmware upgrades for functional improvements which can be downloaded to the SRAM and executed by the on-chip processor.
Does ADI provide protocol stacks for the ADF7030-1?
Analog Devices partners with third party developers to provide protocol stacks such as ZigBee, Wireless M-Bus, 6loWPAN, Sigfox and Wi-Sun for the ADF7030-1. Contact your local sales representative for details.
Should I use a TCXO or XTAL as Reference Clock?
The accuracy of your reference clock has a direct impact on the accuracy of your generated RF signal. A certain amount of frequency error on an RF signal can be tolerated in a system. However, errors become problematic when the radio transmits outside of its designated channel or when the Automatic Frequency Control (AFC) loop of the receiving device cannot handle the error. To understand if a certain reference can be used, users can calculate the maximum expected frequency error based on the spec of the reference used and check if it is compatible with the desired channel spacing of the system and AFC requirements of the radio. Systems with narrow channel spacing (12.5 kHz for example) or low data rates (<10kbps for example), are more sensitive to these types of error and typically use a TCXO as they are more accurate when compared to an XTAL. Another advantage of using a TCXO is faster startup time. The advantage of using an XTAL is that they’re typically lower cost when compared to a TCXO.
How do I generate optimum register settings?
The easiest way to generate the optimum register settings is to use the ADF7030-1 Design Center software. This is part of the ADF7xxx EZKIT Design Suite which can be downloaded from the Analog Devices website.
What is my best starting point for writing host microcontroller code?
ADF7030-1 drivers are provided for the ADuCM3029, a Cortex M3 Microcontroller. These drivers are compatible with other ARM Cortex M-series Microcontrollers.To begin development:
- Download and Install the ADF7xxx EZ-KIT Design Suite
- Download and install the Board Support Package (BSP) software install for the ADuCM3029
- Install IAR Embedded Workbench for ARM 7.70 from the below link. A free trail is available
- Open the ADF7030-1_Design_Package folder
Start -> All Programs -> Analog Devices -> ADF7030-1 Design Package -> Raadio Driver – ADuCM3029
- Follow the instructions in the ReadMe file
Are there BOM differences between boards operating in the different RF bands?
The impedance of the RF output and input pins of the ADF7030-1 must be matched to the impedance of the antenna in order to minimize losses in power between the antenna and the radio. An impedance matching network is built on the PCB to achieve the necessary transformation. Impedance matching networks are made up of capacitors and inductors which are frequency dependent. These components differ between bands. For example, 433MHz will have a different set of values compared to 868MHz. ADI have recommended values for each frequency band.
Harmonic filter requirements and some decoupling capacitor values can also differ between bands and regions.
See the Hardware Reference Manual for more info.