kallisto SY021-PCB top viewkallisto SY021-PCB bottom view


The Kallisto SY021-PCB is a compact sensor module which can be used for application integration as standalone module or assembled on a mezzanine using the Bottom LGA pads. The platform module is delivered with a Zephyr based firmware which makes the system functions accessable over BLE. With the mobile Toolbox App or Python library the moudule can be used instantly to configure sensors and stream sensor data. There are gateway solutions available with partners. Additional functionality is integrated by request and can be purchased from Sensry. Please refer to for additional information.

The module is equipped with 20 sensors and 4 actuators to support a variaty of applications. Additionally, there is an extension header to add additional sensors or periphery to board.


  • LGA Module 55mm x 22mm
  • Multiprotocol Bluetooth® Low Energy
  • Antenna-on-Module
  • Bottom LGA pads for external NFC antenna
  • Bottom LGA pads for Qi charge receiver antenna
  • Low power ARM microcontroller
  • Battery management & LiPo charger
  • USB-C for charging
  • On-board 128 MByte Flash memory for sensor data logging
  • 20 sensor values
  • 4 high current low-side driver


  • Industrial IoT & Retrofitting
  • Smart Wearable
  • Smart Building & Home Automation
  • Track & Trace
  • Beacons

Integrated Sensors

In its standard configuration, the Kallisto® sensor platform is equipped with a set of rigidly attached sensor components which facilitate the simultaneous detection of 20 different measurands at sampling rates which can be individually configured even after shipment. Optionally, additional sensor components can be connected to the SY021-PCB by making use of its multiple I/O interfaces. The integration in the firmware can be purchased from Sensry GmbH. This flexibility enables a customization according to customer requirements and application needs.

MeasurandValue RangeSampling Rate / Hz
Acceleration±4 g ... ±16 g for x-, y-, z-axis12.5 ... 800
Angular velocity (Gyrsocope)±125 °/s ... ±2000 %/s for x-, y-, z-axis25 ... 800
Magnetic Flux±50 gauss for x-, y-, z-axis10 ... 150
High frequency vibration±8 g ...64 g for x-, y-, z-axis0.781 ... 25600 Hz
Temperature-40 ... +85 °C0.1 ... 1
Relative Humidity0 ... 100 %rH0.1 ... 1
Ambient Pressure300 ... 1100 hPa0.1 ... 1
b-VOC (breath-VOC)0.5 ... 1000 ppm0.017 ... 1
eCO2 (equivalient CO2)400 ppm ... infinity0.017 ... 1
IAQ (Index Air Quality)0 ... 1000.017 ... 1
Light-to-digital1.2 ... 10 mW/cm² (for 300 ... 1000 nm wavelength)0.1 ... 8
Noise level (audio amplitude)-135 dbFS ... +3 dBFS (Decibels relative to full scale)0.1 ... 1

Technical Data

Mechanical Parameters

Board TypeLGA with top-side assembly
Size (L x B x H)54 mm x 22 mm x 5 mm
Mounting holes3 x M2
Battery connectorMOLEX 78171-0003
Extension connectorMOLEX 504050-1091
Antennaon-board chip antenna
Power (+ Optional Data)USB-C
Switch ButtonReset
LEDsCharging + BLE connection
kallisto SY021-PCB mechanical view

LGA Pinout

The LGA Pinout is for made for mezzanine assembly and future extensions. The following image shows the top view, the LGA pads are on the bottom side of the PCB.

kallisto SY021-PCB pinout
1EXT UART RXSerial UART RX (same as extension connector)
2EXT UART TXSerial UART TX (same as extension connector)
3EXT GPIO 2GPIO 2 (same as extension connector)
4EXT GPIO 1GPIO 1 (same as extension connector)
5PDM DATAPDM DATA (same as extension connector)
6PDM CLKPDM CLK (same as extension connector)
7I2C SCLI2C Clock (same as extension connector)
8I2C SDAI2C Data (same as extension connector)
9+1V81.8V Regulated Power
11RESERVEDDo not connect!
12RESERVEDDo not connect!
13RESERVEDDo not connect!
14nRESSoC Reset
15SPI MOSISPI Master Out Slave In
17SPI MISOSPI Master In Slave Out
18AC 2Qi Charge Coil Connector 2
19AC 1Qi Charge Coil Connector 1
20+1V81.8V Regulated Power
21EXT 0External Low Side Driver 1
22EXT 1External Low Side Driver 2
23USB+USB Data +
24USB-USB Data -
25EXT 2External Low Side Driver 3
26EXT 3External Low Side Driver 4
27VSYSSystem voltage (VUSB or VBAT)
28+5V5V Board power
29SHPHLDShip Mode Deactivation
31SHPACTShip Mode Activation
32NFC 1NFC coil connector 1
33NFC 2NFC coil connector 2
35ADC 1ADC input 2
36ADC 0ADC input 1
37VBATBattery voltage (+)
38NTCBattery NTC 10kOhm

System Schematic

kallisto SY021-PCB Module Schematic

Electrial Parameters

The PCB module can be powered over USB-C, Qi Charger or LiPo-battery. The board system voltage to power the SoC and periphery is 1.8V.

kallisto SY021-PCB Board Power
Battery (LiPo)VBATV2.30-4.35
LGA Pad +5V+5VV4.15.06.7
LGA Pad +1V8+1V8V1.71.81.9
System voltageVSYSV2.8-5.2
Low-side driver voltage tolerance (4x LGA Pad)VEXTxV12
Low-side driver current tolerance (continious)IEXTxA2.1
LiPo charge currentIcmA100
Quiescent current (in ship mode)IqnA460

Board Power & Battery Charge

Rechargeable LiPo-batteries can be purchased separately from Sensry. The standard capacities are 150 mAh and 500 mAh, other capacities are available on request. There are several possibilities to power the board:

  • USB (w/ or w/o battery)
  • LGA pads (+5V, VBAT or 1.8V)
  • LiPo battery (on battery connector or LGA pad)

To recharge the battery, the board must be powered either with 5V (USB or 5V LGA pad) or via Qi Charge Coil and a standard Qi charge transmitter.

For wireless charging, a receiver coil must be assembled to the LGA pins AC1 and AC2. The recommendation is a TDK WR222230-26M8-G coil:

kallisto SY021-PCB Qi coilkallisto SY021-PCB Qi coil

Any standard Qi smartphone charger can be used to charge the module. The receiver coil must be place close (< 1 mm) to the Qi charger.

Battery Interface

The LiPo battery must include a 10kOhm NTC.

kallisto SY021-PCB battery connector

Extension Interface

The extension interface is equipped with the 10-pin Molex Pico-Lock-Connector 504050-1091 and allows to extend the sensor module with periphery. Molex provide several cable assemblies (MOLEX 15132100x) as a board-to-board connector. The Pinout is described in the following table.

2VSYSSystem voltage
3I2C SDAI²C data interface
4I2C SCLI²C clock interface
5PDM CLKAudio PDM clock interface
6PDM DATAAudio PDM data interface
7GPIO 1GPIO for future use
8GPIO 2GPIO for future use
9UART TXSerial UART transmit
10UART RXSerial UART receive

Using The Ship Mode

The ship mode allows to switch off / Shut-down the device completely while the battery is still connected. It isolates the battery and reduces the quiescent current. The ship mode is designed for transportation and long-term storage. Two LGA pads are available to trigger & control the mode externally.

The ship mode can be activated using the SHPACT LGA pin on the bottom side. While the battery is connected and the USB or Qi Power is disconnected (no battery charge), this pin must be tied to HIGH (> 1.1V) for minimum period of 200 ms. Alternatively, the SHPACT pin is connected to an internal Microcontroller pin, so the mode can be activated by firmware.

To deactivate t ship mode, there are two ways: Either connect the USB plug to apply 5V power source or tie SHPHLD LGA pin low (< 0.4 V) for a minimum period of 200 ms.

kallisto SY021-PCB ship mode