sparkfun ELECTRONICS WRL-15376 Artemis Module User Guide

: June 3, 2024
: sparkfun ELECTRONICS

SparkFun Electronics

Artemis Module
Integration Guide
Version: 1p0p3

1. Overview

The SparkFun Artemis is a Cortex-M4F based BLE module using the Apollo3 micrcontroller from Ambiq. The Artemis is capable of running machine learning algorithms with the low current consumption of 6 A/MHz at 3.3V. The Artemis has an integrated 2.4GHz antenna and incorporates all the necessary circuitry to implement a low power BLE enabled microcontroller.

2. Features

Ultra-low supply current
– 6μA/MHz executing from flash at 3.3V
– 1μA deep sleep mode (BLE Off) with RTC at 3.3V
– Supply voltage: 1.75V to 3.63V with onboard DC/DC regulation

High-performance ARM Cortex-M4 Processor
– Up to 48 GPIO
– 48 MHz nominal clock frequency, with 96 MHz burst mode
– Floating point unit
– Memory protection unit
– Wake-up interrupt controller with 32 interrupts
– Up to 1 MB of flash memory for code/data
– Up to 384 KB of low leakage RAM for code/data
– 16 kB 2-way Associative/Direct-Mapped Cache

Integrated Bluetooth 5 low-energy module
– RF sensitivity: -93 dBm (typical)
– TX: 3 mA @ 0 dBm, RX: 3 mA
– TX peak output power: 4.0 dBm (max)

Small Size
– 15.5 x 10.5mm including antenna

Easy Integration
– Large SMD pads and spacing allow for low cost 2-layer carrier board implementations
– Programming over pre-configured serial bootloader or JTAG

Ultra-low power ADC
– 14 bit ADC at up to 2.67 MS/s effective continuous, multi-slot sampling rate
– 15 selectable input channels
– Voltage Comparator
– Temperature sensor with +/-3ºC accuracy

ISO7816 Secure ‘Smart Card’ interface

Flexible serial peripherals
– 1x 2/4/8-bit SPI master interface
– 6x I2C/SPI masters for peripheral communication
– I2C/SPI slave for host communications
– 2x UART modules with 32-location Tx and Rx FIFOs
– PDM for mono and stereo audio microphone
– 1x I2S slave for PDM audio pass-through

Rich set of clock sources
– 32.768 kHz XTAL oscillator
– Low frequency RC oscillator – 1.024 kHz
– High frequency RC oscillator – 48/96 MHz
– RTC based on Ambiq’s AM08X5/18X5 families

3. Mechanical Specifications

Module Dimensions	15.5 x 10.5 x 2.3mm
Weight	0.6g
Antenna	2.4 – 2.5GHz Chip

Recommended PCB Layout:

WRL-15376 - PCB Layout 57 @ 0.4×0.6
2 @ 0.6×0.6
All Dimension in Millimeters

Top View
Copper Pad and Paste Aperture Dimensions

Recommended Soldermask Layout:

WRL-15376 - Soldermask Layout 1

WRL-15376 - Soldermask Layout 2 Solder Mask Dimensions

4. Pad Signals and Assignment

Module Pad No.

| Name| Pin Function| Description
---|---|---|---
1| GND| Power|

Ground

2

RX pin for serial bootloading

4

| GPIO39| |
5|

GPIO40

| |

6

Hold pin high during reset to initiate bootloader

8

TX pin for serial bootloading

10

12

14

SPI, PDM, SCC, UART, I2S, and clock sources. Please

16

18

| GPIO23| |
19|

GPIO27

| |

20

| GPIO14| |
21|

GPIO28

| |

22

| GND| Power|
23|

GPIO6

| |

24

| GPIO32| |
25|

GPIO25

| |

26

| GPIO12| |
27|

GPIO26

| |

28

| GPIO13| |
29|

GPIO15

| |

30

| GPIO33| |
31|

GPIO34

| |

32

| GPIO11| |
33|

GPIO29

| |

34

Connection for external 32.768kHz RTC crystal

36

| VDD| Power|
37| VDD|

Power

|

38

| GND| Power|
39| GND|

Power

|

40

| GPIO19| |
41|

GPIO18

| |

42

| GPIO16| |
43|

GPIO17

| |

44

| GPIO31| |
45|

GPIO41

| |

46

| GPIO45| |
47| GND|

Power

|

48

| GPIO2| |
49|

GPIO1

| |

50

| nRESET| System Reset| Pull pin low to reset system
51|

GPIO0

| |

52

| GPIO43| |
53|

GPIO42

| |

54

| GPIO3| |
55|

GPIO36

| |

56

| GPIO38| |
57|

GPIO37

| |

58

| GPIO44| |
59| GND|

Power

|

WRL-15376 - Overview of Pad Functions Overview of Pad Functions
Note: Apollo Pad# maps to GPIO# on Artemis

5. Designing Artemis Into End Application

Routing and Recommended Keep Out

WRL-15376 - Designing Artemis Into End Application

An example layout with ground pour and ground vias

The Artemis module was designed to be implemented onto low cost 2-layer PCBs with easy 8mil trace/space routing. A good ground connection is essential. Routing under the module is allowed. Keep all ground pours away from the antenna area. If mechanical exposure allows for it the antenna can be extended over the edge of the PCB for increased reception.

6. Programming

WRL-15376 - Two example programming interfaces

Two example programming interfaces

Artemis can be programmed using the standard JTAG interface or with a serial bootloader. The Artemis module can be routed to USB to serial circuit or an industry standard JTAG connector for more advanced programming and debugging. For more information on ARM programming, including JTAG interfaces, check out our ARM Programming Tutorial.

SparkFun Bootloader

We’ve designed a baud rate flexible bootloader that is run at each power on reset. What does baud rate flexible mean exactly? The computer initiates communication at a given baud rate (921600bps for example) and the Artemis auto-detects the baud rate and transfers the bulk of the binary data at the agreed upon rate. This enables upload speeds up to 921600bps; significantly reducing upload times. A flexible rate allows computer systems that may have problems at higher rates to select the rate that works best. This bootloader is the preferred method for uploading sketches and user code that needs quick and reliable means of getting new code onto the Artemis.

WRL-15376 - SparkFun Bootloader

Once you’ve selected an Artemis target board additional menu options will appear the next time you open the Tools menu. The SVL Baud Rate options will allow you to change the upload speed. 921600bps is the recommended speed as it’s extremely fast to update new sketches. However, there are some platforms (Linux flavors) where the standard CH340 USB to serial drivers don’t operate well at speeds higher than 115200. So if you run into upload problems, consider reducing the upload speed. For more information about Linux upload issues see this forum post and consider upgrading with these drivers.

Just like the classic Arduino Uno, Arduino Mega, etc, the bootloader is activated by resetting the board. A single 0.1uF capacitor between DTR and reset is all that is needed to cause the Artemis to reset and enter bootload mode. If no new firmware is detected within a short amount of time (50ms), user code is run.

If you’re into niche electrical engineering discussions on things like bootloaders, you can read more about the Artemis bootloader here.

Factory Bootloader

In addition to the SparkFun Artemis bootloader, we program every Artemis with the Ambiq factory Secure Bootloader (SBL). This bootloader is best used for low-level updates to devices that need to have a secure provenance. The bootloader is activated at reset if pin 47 is high and communicates at 115200. The bootloader will then wait indefinitely for new binary data. SparkFun provides a python tool as well as an executable to communicate with this bootloader.

Bootloader Reset Circuit

This style of bootloading is slightly different from bootloaders that you may be accustomed to. The STK500 bootloader that runs on most ATmega328 based Arduinos is run automatically at reset, then times out and the user’s code is run. The Artemis bootloader is similar but requires an extra pin (the Bootload pin) to be held high. To make using Artemis as cheap and easy as possible we’ve designed a simple RC circuit that can be implemented on your design using USB-to-serial ICs with the bare minimum control pins (the CH340E has only RTS) and still allow for factory bootloader activation. If you suspect you will need to modify the SparkFun Artemis Bootloader (described above) or if you need to use the secure bootload toolchain, the circuit above can be used to bootload using a single pin (DTR or RTS is supported). This single-pin reset and bootload solution is ideal for any USB to serial implementation that has control pins exposed (CH340, CP210x, FT232, etc).

Heads up! You will never damage or brick the Artemis but using the Ambiq Secure Bootloader tools will overwrite the SparkFun bootloader removing the faster upload abilities. We don’t recommend using the Ambiq Secure Bootloader for general Arduino programming.

Don’t select Ambiq Secure Bootloader unless you know what you’re doing

To load new code onto your Artemis module using the Ambiq bootloader toolchain select the Ambiq Secure Bootloader option in the Arduino Tools->Bootloader menu. These tools will modify your binary and package them with various security headers. The code will load at 115200bps and may fail. Hit upload again if the process fails.

How the Single Pin RC Circuit Works

By pulling DTR (or RTS) low, the module is reset. After 10ms, DTR is pushed high in software. This causes the bootload pin to be high for 100ms allowing the bootloader to run. Opening of a serial port causes DTR to go low causing the module to reset, but because DTR stays low during normal serial operations the module does not enter the SBL and instead proceeds to run the SparkFun Artemis Bootloader.

We have modified the Ambiq python bootload tool so that both DTR and RTS are driven at the same time, and in the same way, so you can use either RTS or DTR to bootload the Artemis. Our Ambiq SBL tools then drive DTR/RTS high to enter the the factory bootloader.

If you prefer, the bootload pin can be broken out to a button. When the user holds the button and resets the board the Artemis will enter bootload mode and stay there until a bootload cycle completes or a reset occurs. This method works well but requires the user’s interaction every time new code needs to be loaded.

7. Reflow Profile and Cleaning

Cleaning

The use of “No Clean” paste is recommended as it does not require a wash phase after reflow. Washing a final assembly that uses the Artemis is not recommended as water may be captured under the module and/or RF shield causing part degradation.

Recommended Reflow Profile

The Artemis module follows standard reflow handling and processing. Please refer to the Jedec J-STD-020-D.1 reflow profile. Multiple reflow exposures are not recommended.

8. Tape and Reel Packaging

Artemis comes on 24mm reels of 500pcs with 16mm pocket spacing as shown below.

POCKET SIZE

Ao –| 11.00mm [.433”]
Bo –| 16.50mm [.650”]
Ko –| 2.90mm [.114”]

WRL-15376 - Dimensions 1

WRL-15376 - Dimensions 2

CUSTOMER APPROVAL TO BUILD MOLD
X DATE

PART CONFORMS TO
E1A-481-C STANDARDS|
---|---

THIS DRAWING CONTAINS PROPRIETARY DESIGN INFORMATION AND REMAINS ALONG WITH THE PRODUCT OR PRODUCTS REPRESENTED HERE IN THE PROPERTY Of TEK PAK, INC.
THIS DOCUMENT AND THE INFORMATION IT CONTAINS MAY NOT BE COPIED, TRANSMITTED TO, OR USED BY ANY THIRD PARTY WITHOUT THE EXPRESS WRITTEN APPROVAL OF TEK PAK, INC.

NOTE:

ALL DIMENSIONS IN MILLIMETERS [INCHES]
10 SPROCKET HOLE PITCH CUMULATIVE TOLERANCE ± 0.2mm

UNLESS OTHERWISE NOTED ALL TOLERANCES ARE AS FOLLOWS:
ANGLES: ± 1°
DIM: XX ± .10 mm

PART NO: 100010490

|

DATE

|
DRAWN BY: GLP|

3-31-08

9. Regulator Testing and Configuration

If necessary the Artemis module can be configured for host product evaluation for different operational conditions. In other words, if Artemis is implemented into a host system that needs secondary certifications the Artemis can be loaded with test firmware to put the radio into different constant transmission or reception states to verify the end device does not emit spurious emissions caused by the Artemis. The test firmware and documentation for implementation is located in the Ambiq SDK under ‘uart_ble_bridge’.

10. Regulatory Statements

FCC Statements

FCC Statements
This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions:

This device may not cause harmful interference, and
This device must accept any interference received, including interference that may cause undesired operation.

Note: This product has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This product generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this product does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:
– Reorient or relocate the receiving antenna.
– Increase the separation between the equipment and receiver.
– Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
– Consult the dealer or an experienced radio/TV technician for help.

Warning: Changes or modifications to this unit not expressly approved by the party responsible for compliance could void the user’s authority to operate the equipment.

FCC Radiation Exposure Statement
This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. End users must follow the specific operating instructions for satisfying RF exposure compliance.

FCC Modular Usage Statement
Note 1: This module certified complies with RF exposure requirements under mobile or fixed condition; this module is to be installed only in mobile or fixed applications.

A mobile device is defined as a transmitting device designed to be used in other than fixed locations and to generally be used in such a way that a separation distance of at least 20 centimeters is normally maintained between the transmitter’s radiating structure(s) and the body of the user or nearby persons. Transmitting devices designed to be used by consumers or workers that can be easily re-located, such as wireless devices associated with a personal computer, are considered to be mobile devices if they meet the 20 centimeter separation requirement.

A fixed device is defined as a device is physically secured at one location and is not able to be easily moved to another location.

Note 2: Host product manufacturers must provide in their user manual the required RF exposure information for mobile & fixed usage of this module. Host product manufacturers must use the following RF exposure statement in their user manual “This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. This equipment should be installed and operated with a minimum distance of 20 cm between the radiator and all persons. This transmitter must not be co-location or operating in conjunction with any other antenna or transmitter.”

Note 3: Any modifications made to the module will void the Grant of Certification, this module is limited to OEM installation only and must not be sold to end-users, end-user shall have no manual instructions to remove or install the device, only software or operating procedure shall be placed in the end-user operating manual of final products.

Note 4: Additional testing and certification may be necessary when multiple modules are used.

Note 5: The module may be operated only with the integral chip antenna with which it is authorized.

Note 6: To ensure compliance with all non-transmitter functions the host manufacturer is responsible for ensuring compliance with the module(s) installed and fully operational. For example, if a host was previously authorized as an unintentional radiator under the Supplier’s Declaration of Conformity procedure without a transmitter certified module and a module is added, the host manufacturer is responsible for ensuring that the after the module is installed and operational the host continues to be compliant with the part 15B unintentional radiator requirements. Since this may depend on the details of how the module is integrated with the host, the manufacturer shall provide guidance to the host manufacturer for compliance with the part 15B requirements.

Note 7: The FCC ID label on the final system must be labeled with “Contains FCC ID: 2ASW8- ART3MIS” or “Contains transmitter module FCC ID: 2ASW8- ART3MIS”.

Note 8: The FCC rule/s for this module are CFR 47 Part 15 Subpart C.

Note 9: This modular transmitter is only FCC authorized for the specific rule parts listed on its grant. The host product manufacturer is responsible to any other FCC rules that apply to the host not covered by the modular transmitter grant of certification. The final host product will require Part 15 Subpart B compliance when the modular transmitter is installed.

ISED Statements
This device complies with Innovation, Science and Economic Development Canada’s license-exempt RSS standard(s). Operation is subject to the following two conditions:

this device may not cause interference, and
this device must accept any interference, including interference that may cause undesired operation of the device.

Under Innovation, Science and Economic Development Canada’s regulations, this radio transmitter may only operate using the integral antenna under which it was approved.

ISED RF Exposure Statement
This equipment complies with ISED radiation exposure limits set forth for an uncontrolled environment. This equipment should be installed and operated with minimum distance 20cm between the radiator & your body. This transmitter must not be co-located or operating in conjunction with any other antenna or transmitter.

ISED Modular Usage Statement
NOTE 1: When the ISED certification number is not visible when the module is installed inside another device, then the outside of the device into which the module is installed must also display a label referring to the enclosed module. This exterior label can use the wording “Contains transmitter module IC: 25186-ART3MIS” or “Contains IC: 25186-ART3MIS”.

11. Revision History

Revision	Date	Description
1p0p0	June-2-2019	Initial Release
1p0p1	July-23-2019	Add Regulatory Statements

Add Programming
Move recommended layout to new section
1p0p2| August-9-2019 | Update regulator information. Add regulatory testing section. Add reflow information. Add tape and reel diagram.
1p0p3| August-12-2019 | Updated regulator information.

SparkFun Electronics Inc – Artemis Integration Guide – 1p0p3