ambiq micro Apollo4 Blue Plus User manual

QUICK START GUIDE
Apollo4 Blue Plus (KBR) EVB
(EVB Revision 1.0)
Ultra-low Power Apollo SoC Family
Doc. ID: QS-A4BP_KBR-1p0
Document Revision 1.0, September 2022

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Table of Content
1. Introduction ............................................................................................................. 6
2. Document Revision History..................................................................................... 6
3. Reference Documents and Software...................................................................... 7
4. Quick Start .............................................................................................................. 7
5. Overview of the Apollo4 Blue Plus (KBR) EVB....................................................... 8
6. Debug Interface .................................................................................................... 12
7. Software Development Tools................................................................................ 14
8. Power Supply Options and Measuring Current..................................................... 15
9. Non-Power Solder Bridges ................................................................................... 19
10. Ordering Information........................................................................................... 21

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List of Figures
Figure 1. Apollo4 Blue Plus (KBR) EVB...................................................................... 8
Figure 2. Apollo4 Blue Plus (KBR) Plus EVB - Major Top Side Components............. 8
Figure 3. Apollo4 Blue Plus (KBR) Plus EVB - Major Bottom Side Components ....... 9
Figure 4. Apollo4 Blue Plus (KBR) Plus EVB - Top Side Parts Location.................... 9
Figure 5. Apollo4 Blue Plus (KBR) Plus EVB - Bottom Side Parts Location............. 10
Figure 6. Apollo4 Blue Plus (KBR) EVB Using On-board J-Link Debugger.............. 12
Figure 7. Apollo4 Blue Plus (KBR) EVB’s DEBUG IN Header (J13)......................... 13
Figure 8. Apollo4 Blue Plus (KBR) EVB Power Supplies Solder Bridge Connection 15
Figure 9. Apollo4 Blue Plus (KBR) EVB USB Load Switch Circuit ........................... 16
Figure 10. Apollo4 Blue Plus (KBR) EVB VDD18 Load Switch Circuit ..................... 16
Figure 11. Apollo4 Blue Plus (KBR) EVB Voltage Test Points on Header J2........... 17
Figure 12. Apollo4 Blue Plus (KBR) EVB Voltage Selection on Header J3 .............. 17
Figure 13. Audio Jack J18 and AUDADC Audio Source Selections ......................... 20
Figure 14. Audio Header J17 .................................................................................... 20

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List of Tables
Table 1: Document Revision History........................................................................... 6
Table 2: Peripherals Supporting Solder Bridge Connections.................................... 19
Table 3: EVB Ordering Information........................................................................... 21
Table 4: SoC Ordering Information........................................................................... 21

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1. Introduction
This document provides guidance for setting up the Apollo4 Blue Plus (KBR) Evaluation Board (EVB),
revision 1, part number AMA4BPEVB, to get started executing code examples, measuring power
consumption in various configurations, and beginning software development.
This version of the EVB contains silicon version C0 of the Apollo4 Blue Plus (KBR) which supports
Bluetooth 5.1 Low Energy(1).
2. Document Revision History
1. The Bluetooth® word mark and logos are registered trademarks owned by the Bluetooth SIG, Inc. and any use of such
marks is under license. Other trademarks and trade names are those of their respective owners.
FCC Regulatory Notice
This kit has not been authorized under the rules of the FCC and is designed to (1) allow product
developers to evaluate electronic components and circuitry associated with the kit to determine
whether to incorporate such items in a finished product, and (2) enable software developers to
write software applications for use with the end product.
This kit is not a finished product and may not be resold or otherwise marketed. Developers using
this reference design in their product are responsible for all required FCC equipment
authorizations.
Operation is subject to the condition that this product not cause harmful interference to licensed
radio stations and that this product accept harmful interference. Unless the assembled kit is
designed to operate under part 15, part 18 or part 95 of 47 CFR Chapter I - FCC, the operator of
the kit must operate under the authority of an FCC license holder or must secure an experimental
authorization under part 5 of the latter chapter.
Rev # Date Description
1.0 September 2022 Document initial public release
Table 1: Document Revision History

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3. Reference Documents and Software
The following items, which can be downloaded from the Apollo4 Blue Plus Product Page link on https://
ambiq.com/, may be useful in understanding and using the EVB.
▪ EVB Schematic
▪ Datasheet
▪ Programmer’s Guide
▪ Errata List
▪ AmbiqSuite SDK
4. Quick Start
The EVB Kit comes with the following items:
▪ Apollo4 Blue Plus (KBR) Evaluation Board (EVB) revision 1
▪ USB Type C cable
▪ Four adhesive-backed rubber feet
▪ Extra jumpers
Caution: The EVB has components loaded on the back of the board. Care should be taken to not damage
these components. The included rubber feet should be applied to the bottom of the board to prevent direct
contact between the components and a desk surface.
The EVB comes with jumpers pre-configured for default operation. Also, it has been pre-programmed with
the FreeRTOS Fit example program. To start EVB program execution, connect the USB-C cable from a
USB port on a PC to the J-Link USB connector (J6) on the EVB, and turn on the power switch (SW4). The
blue LED under the power switch should illuminate.
To observe program execution, do the following steps:
▪ Start a Bluetooth explorer application such as LightBlue Explorer on a mobile phone or other device that
can serve as a Bluetooth host device.
▪ If diagnostic message are desired, start a SWO session by bringing up a Segger J-Link SWO Viewer
(see Software Development Tools section for link to Segger tools download site). For “device” select
“AMA4B2KP-KBR” and set SWO clock to 1000 KHz.
▪ Reset the board by pressing switch SW3.
▪ After reset, the Apollo4 Blue Plus (KBR) will start advertising and Bluetooth traffic will appear in the SWO
viewer. One of the messages in the SWO viewer will indicate that this device called “Fit” (EVB) is adver-
tising.
▪ The device “Fit” will appear in the list of devices in the host application (App). By selecting it, the host will
connect to the “Fit” device on the EVB.
▪ The App and Fit will exchange several commands and responses (events) until the SWO message
reports that “Fit got evt 41).
The AmbiqSuite SDK provides many example programs that may be run on the EVB. To run these
examples, download the SDK via the link provided above and select any of the pre-built examples in the
SDK at /boards/apollo4p_blue_kbr_evb/examples.

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5. Overview of the Apollo4 Blue Plus (KBR) EVB
The Apollo4 Blue Plus (KBR) EVB, version 1, features Arduino-compatible headers and an integrated J-
Link debugger:
Figure 1. Apollo4 Blue Plus (KBR) EVB
Figure 2. Apollo4 Blue Plus (KBR) Plus EVB - Major Top Side Components

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Figure 3. Apollo4 Blue Plus (KBR) Plus EVB - Major Bottom Side Components
Figure 4. Apollo4 Blue Plus (KBR) Plus EVB - Top Side Parts Location

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Figure 5. Apollo4 Blue Plus (KBR) Plus EVB - Bottom Side Parts Location
The EVB has these features:
▪ Apollo4 Blue Plus (KBR) SoC in the BGA package (AMA4B2KP-KBR)
▪ Low power reference design
▪ Multiple power/clock options
▪ USB Type C connector for power/download/debug
▪ USB Type C connector for power/data to Apollo4 Blue Plus (KBR)
▪ On-board PCB (MIFA) antenna
▪ Segger J-Link debugger
▪ Debugger-in port (J13) (SWD or ETM)
▪ Three user-controlled LEDs
▪ Two push buttons for application use, plus a reset push button
▪ Power slide switch with LED power indicator
▪ Five Arduino-style headers (J7, J9-J12) for pin/power access to a shield board
▪ Test points for power measurements
▪ High-speed connector (J8 - QSH-030-01-L-D-A) for interfacing to displays and/or high-speed memory
▪ RF switch/connector (Murata MM8430-2610RA1) for BLE PHY testing
▪ Multiple solder-bridge options for power supply flexibility and peripheral access options
▪ 3.5 mm audio jack (SJ-435107) for evaluating low-power analog audio interface
▪ CE Mark and RoHS compliant
Caution: The EVB has components loaded on the back of the board. Care should be taken to not damage
these components.
5.1 Secure Boot on the Apollo4 Blue Plus (KBR) SoC
Apollo4 Blue Plus (KBR) SoC parts from the Ambiq factory are preprogrammed with a Secure Bootloader
and an uninitialized Customer Info Space, referred to as INFO0. Initial provisioning of the part would
include programming a valid INFO0 and programming the main firmware image in the flash. The Apollo4
Blue Plus (KBR) EVB is shipped with the INFO0 configuration pre-programmed with optimal settings for
the EVB layout:

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1. Default boot to non-secure mode
2. Enable Boot Override to Push Button on GPIO18 (OTP setting) - BTN0/SW1
3. Enable wired updates over UART0
A. UART0 is mapped to J-Link (OTP Setting).
B. Baud rate is 115200 bps, no-parity, 8-bit data length, no flow control.
C. Timeout is 3 seconds.
For your reference, the following settings are programmed into INFO0 on the Apollo4 Blue Plus (KBR) SoC
resident on the EVB:
▪ Simo Buck is NOT enabled.
▪ Secure Bootloader (SBL) interface is configured to UART using GPIO47 and GPIO60, which allows
secure boot to be performed over the J-Link COM interface of the EVB.
▪ SBL override pin is configured to GPIO18 which is BTN0/SW1 on the EVB.
▪ All Flash and Debugger protection features are disabled.
For information on changing the INFO0 settings as well as using the Secure Bootloader, please refer to the
README.txt file, which can be found in the tools\apollo4b_scripts folder of the latest SDK release
supporting the Apollo4 family. This folder contains a number of python scripts to demonstrate generation of
INFO0 settings, customer main images, and the creation of images for the Wired Update protocol over
UART.

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6. Debug Interface
Figure 6 shows the Apollo4 Blue Plus (KBR) EVB set up for standard debug using the on-board J-Link
debugger and on-board power supply. The on-board J-Link debugger is on the other side of the board and
not shown in the figure.
Figure 6. Apollo4 Blue Plus (KBR) EVB Using On-board J-Link Debugger
The debug interface is supported by standard J-Link drivers from Segger. Please refer to “Software
Development Tools” on page 14 for more details on J-Link debug support.
6.1 Use of External Debugger
This EVB also supports the use of an external Cortex SWD debug interface through a 20-pin debug header
(DEBUG IN - J13) as shown in Figure 7. See the EVB schematic for connector pinout.

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Figure 7. Apollo4 Blue Plus (KBR) EVB’s DEBUG IN Header (J13)
No jumper changes are required to use an external debug adapter. Simply connect the external debug
adapter with a ribbon cable connector to the “DEBUG IN” header.
NOTE: Remove protective guard before attempting to connect to the DEBUG IN header.

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7. Software Development Tools
The standard Segger J-Link debug interface is used on the Apollo4 Blue Plus (KBR) EVB. Please install
the latest Segger J-Link software, and configure your preferred development IDE (Keil, IAR, or Eclipse) to
use J-Link debug interface.
Links to development tools that support Apollo4 Blue Plus (KBR):
▪SEGGER J-Link Software (7.70d or later): https://www.segger.com/downloads/jlink
▪ KEIL uVision 5 (MDK5.34 or later): https://www.keil.com/demo/eval/arm.htm
▪ Latest Keil Pack (Also used by Eclipse): http://www.keil.com/dd2/pack/#/third-party-download-dialog
▪ IAR Version (8.42.2 or later): https://www.iar.com/iar-embedded-workbench/tools-for-arm/arm-cortex-m-
edition/
▪ GCC 5.3.1: https://gcc.gnu.org
Regardless of IDE used, please install the Segger J-Link software. All of the above development
environments support J-Link, but you must have the latest J-Link software installed. Most alternate
development environments also are supported by J-Link.
Please refer to the AmbiqSuite Getting Started Guide (AMSDKGS) provided with any SDK release for
more details on setting up development IDEs to use J-Link.

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8. Power Supply Options and Measuring Current
The Apollo4 Blue Plus (KBR) EVB is intended to operate off of a 5 V supply, which is used to generate
downstream voltages.
There are two power supply options for the EVB SoC:
▪ Operate at 1.9 V by default as provided by the on-board power supply (referred to as nominal
“VDD_1.8V”). This can be adjusted to 1.8 V by shorting SB4 shown on the Power Supplies page of the
EVB schematic(1).
▪ Provide externally supplied power.
The EVB utilizes solder-bridges for connecting and disconnecting rails from power supplies, whether
generated on-board or off-board. Figure 8 shows the solder-bridge connection strategy between various
on-board power supplies and the SoC’s power rails.
Figure 8. Apollo4 Blue Plus (KBR) EVB Power Supplies Solder Bridge Connection
Figure 9 shows the USB load switch circuit producing the voltage supplied to VDDUSB33 and
VDDUSB0_9 through solder-bridges SB13 and SB11, respectively. These solder bridges are shorted by
default.
1. Refer to the EVB schematic and assembly drawing for purpose and location of all solder bridges on the
EVB.

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Figure 9. Apollo4 Blue Plus (KBR) EVB USB Load Switch Circuit
Similarly, Figure 10 shows the load switch circuit producing the voltage supplied to the MIPI DPHY VDD18
supply through solder-bridge SB9. This solder bridge is also shorted by default.
Figure 10. Apollo4 Blue Plus (KBR) EVB VDD18 Load Switch Circuit

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As shown in Figure 11 and Figure 12, headers J2 and J3 provide easy access to the various system and
chip-level power supplies present on the EVB. These can be used in conjunction with the above solder-
bridges to measure current, monitor voltage, or provide externally generated power to each specific rail.
Figure 11. Apollo4 Blue Plus (KBR) EVB Voltage Test Points on Header J2
Figure 12. Apollo4 Blue Plus (KBR) EVB Voltage Selection on Header J3
8.1 Measuring Current
If the user wants to use a separate power supply for the EVB, then SB3 shown in Figure 8 should be cut,
and either SB5 should be shorted or pins 3 and 4 of J3 should be jumped. The external power rail can be
applied to VDD_EXT on J3, pin 3. Consult the electrical specifications in the Apollo4 Blue Plus (KBR)
Datasheet for the acceptable operating range for VDD_MCU.
Note: The J-Link I/O voltage should be set to the new VDD_IO of the chip, and therefore SB84 (not shown
in Figure 8) should be opened and SB85 should be shorted (soldered).
Current consumption of the Apollo4 Blue Plus can be measured by connecting an ammeter between pins
1 and 2 of J3 after SB3 has been cut. For increased accuracy of this current measurement, especially
when measuring Deep Sleep current, SB76 also needs to be cut on revision 1 of the EVB - see Figure 4 for
location. This disconnects the RSTn line from the J-LINK controller to the MCU. J-LINK can still
communicate with and program the Apollo4 Plus, but cannot reset the device after reprogramming. To
prevent having to manually reset the device after reprogramming, SB76 can be re-shorted to allow J-LINK
to reset the device.

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Use of the EVB using the on-board SoC supply may be restored by disconnecting the external supply (if
connected) and either shorting SB3 once again or jumping between pins 1 and 2 of J3. The J-Link I/O
voltage also should be restored.
As another example, if it is desired to measure the BLE current provided by the VDD_1.8V source for the
Apollo4 Blue Plus (KBR) package, SB7 may be cut, and a current probe may be applied between
VDD_MCU on J2, Pin 1 and VDDB on J2, Pin 2. After measuring current, SB7 may be shorted or a jumper
may be placed across J2, pins 1 and 2.

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9. Non-Power Solder Bridges
9.1 Solder Bridges for Reducing Trace Length to Optimize Performance
The following peripherals support solder-bridge connections, which allow for optimized performance by
reducing overall trace length at the cost of losing connectivity to their respective GPIO headers. Note that
these connections can be reset by applying solder across the solder-bridge.
Additionally, the LED indicators can be disconnected from GPIO30, GPIO90 and GPIO91 by opening their
respective solder-bridges (SB37, SB38, and SB39). GPIO47, GPIO58, GPIO59 and GPIO60 are used for
UART communication with the on-board J-Link. Opening SB80-SB83 frees these pins for exclusive use
with the standard GPIO headers J10 and J12.
9.2 Solder Bridges for Audio Selectivity
As shown in Figure 13, a single audio jack, J18, provides stereo audio input routed to AUDADC (also
referred to as LPADC) inputs on the SoC. Alternatively, up to 4 single-ended or 2 differential pair audio
signals as shown in Figure 14 can be input on connector J17 which is routed on the EVB as differential
pair(s) to AUDADC inputs. The default (shorted) solder bridge configuration enables either of these input
options.
Peripheral GPIO Description
Display Controller, MSPI0 37, 64-73
Opening the following corresponding solder-bridges shown in
Figure 4 connects these GPIO exclusively to J8, with minimal trace
stubs: SB36, SB56, SB55, SB30 - SB35, SB53, SB54.
ETM 50-54, 55 (open by default)
Opening the following corresponding solder-bridges shown in
Figure 4 connect these GPIO exclusively to J13: SB42 - SB46, SB57.
SWO is default connection to J13 (shared with GP55, SWTRCTL)
Table 2: Peripherals Supporting Solder Bridge Connections

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Figure 13. Audio Jack J18 and AUDADC Audio Source Selections
Figure 14. Audio Header J17