Zest_Battery_LiPo
Overview
The Zest_Battery_LiPo is an electronics development board for 6TRON opensource platform. It is a complete Lithium Polymer battery management unit.
The board includes a standalone charger from Maxim Integrated. The circuit is set for an 800mA.h battery. The charge current and the input current limit can be adjusted through onboard resistors. The IC presents an integrated PowerPath that permits the powering of the system while charging the battery. 2 independent power inputs can be used simultaneously: an external power source (the jack on the Zest_Core for example) and a micro USB-B header present on the charger board. In the latest case, the current is limited to 500mA. 3 LED indicators inform of the status of the charger: Power Source Connected, In-Charge and Charging Error.
The second circuit is a gas gauge from Maxim Integrated. The circuit only requires minimal programming information to start operation (battery capacity and min battery voltage). Then through a build-in algorithm, the gauge progressively learns the performances of the battery. Different alerts can be programmed such as a battery-low indicator. This alert signal is fed onto the extension header to trigger the controller and initiate a readout of the gauge registers.
The gauge is continuously powered while the battery is connected, but the battery can be disconnected from the charger through the switch SW1.
The Gauge includes specific interface circuitry for 2 NTC. One is mounted on the board. If the battery protection circuit includes an NTC, the second input can be used. For this purpose, 2 types of batteries can be used:
- For batteries with build-in NTC, a 3-pin Molex header is populated
- For simple batteries without NTC, a 2-pin JST header can be substituted to the 3-pin header
In the case of an external power management unit would be present, the output supply from the charger circuit could be connected to the external board through SMT header J.
Specifications
| Category | Zest_Battery |
|---|---|
| MAX8903 | 2A ,1 Cell DCDC battery charger for USB and power adapter |
| MAX17201 | Stand-alone model gauge M5 fuel gauge |
| Connectivity | 80-pin 6TRON header Molex 530480310 3-pin header for the battery A micro USB type B for a second source of energy 2-pin SMD header BM02B-ACHSS-GAN-ETF for direct access to the charger PowerPath output |
| Board size | 80 x 39 mm |
| Power Sources | 4.5 to 12V, 1.5A from the Jack on the Zest_Core 5V - 500mA from the integrated micro USB B header 4.5 to 12V, 1.5A from the 80-pin Interface Header |
Block Diagram
The graphics below gives an overview of the board features and connections.
80-pin 6TRON connector
| Description | 6TRON function | Pin number | Pin number | 6TRON function | Description |
|---|---|---|---|---|---|
| - | VJACK | 1 | 2 | VJACK | - |
| - | VJACK | 3 | 4 | VJACK | - |
| - | VHV | 5 | 6 | VHV | - |
| - | VHV | 7 | 8 | VHV | - |
| - | DIO8 | 9 | 10 | VIN_EN | - |
| - | DIO7 | 11 | 12 | DIO9 | - |
| - | DIO6 | 13 | 14 | DIO10 | - |
| - | MD | 15 | 16 | DIO11 | - |
| - | DIO5 | 17 | 18 | DIO12 | - |
| Ground | GND | 19 | 20 | GND | Ground |
| Ground | GND | 21 | 22 | GND | Ground |
| 6TRON Stack Power Supply | VIN | 23 | 24 | VIN | 6TRON Stack Power Supply |
| 6TRON Stack Power Supply | VIN | 25 | 26 | VIN | 6TRON Stack Power Supply |
| - | VB_EN | 27 | 28 | DIO13 | - |
| - | VB_OUT | 29 | 30 | DIO14 | - |
| - | DAC1 | 31 | 32 | DIO15 | - |
| - | ADC4 | 33 | 34 | DIO16 | - |
| - | ADC3 | 35 | 36 | DIO17 | - |
| - | ADC2 | 37 | 38 | DIO18 | - |
| - | ADC1 | 39 | 40 | GND | - |
| - | EXT_NRST | 41 | 42 | GND | - |
| - | DIO4 | 43 | 44 | VREF | - |
| - | DIO3 | 45 | 46 | DIO19 | - |
| - | DIO2 | 47 | 48 | DIO20 | - |
| - | DIO1 | 49 | 50 | DIO21 | - |
| - | WKUP | 51 | 52 | DIO22 | - |
| - | ICAPT | 53 | 54 | DIO23 | - |
| - | PWM3 | 55 | 56 | DIO24 | - |
| - | PWM2 | 57 | 58 | DIO25 | - |
| - | PWM1 | 59 | 60 | DIO26 | - |
| - | SPI1_SS | 61 | 62 | DIO27 | - |
| - | SPI1_SCK | 63 | 64 | DIO28 | - |
| - | SPI1_MISO | 65 | 66 | DIO29 | - |
| - | SPI1_MOSI | 67 | 68 | DIO30 | - |
| - | UART1_TX | 69 | 70 | DIO31 | - |
| - | UART1_RX | 71 | 72 | DIO32 | - |
| I2C1_SDA | I2C1_SDA | 73 | 74 | DIO33 | - |
| 2C1_SCL | I2C1_SCL | 75 | 76 | DIO34 | - |
| - | CAN1_TX | 77 | 78 | DIO35 | - |
| - | CAN1_RX | 79 | 80 | DIO36 | - |
Software Support
Zest_Battery_LiPo provide a demo example developed using MBed Os. The board can run on Zest Core development boards.
Ressources
Application notes
-
Powering 6TRON board
-
exemple soft