# ATTINY841 BMS ## Description DIY BMS using ATTINY841-SSU this hardware has a higher balance current, fuse and TVS diode to help with voltage spikes. Most importantly, an external crystal to the micro controller (attiny841) which means the device is more reliable in low voltage situations ## Project Details - **Owner:** flux - **Created:** 9/28/2023 - **Last Updated:** 3/12/2025 - **Visibility:** Public - **Stars:** 2 - **Forks:** 17 - **Copies:** 1 ## Key Components ### D1 — [AZ432ANTR-E1](https://www.flux.ai/adrian95/az432antr-e1~0ck.md) - Part Type: Integrated Circuit - Manufacturer Name: Diodes Incorporated - Datasheet URL: https://www.diodes.com/assets/Datasheets/products_inactive_data/AZ432.pdf - Manufacturer Part Number: AZ432ANTR-E1 **Pins:** - P1 - P2 - P3 ### D2 — [SMBJ5.0A](https://www.flux.ai/adrian95/smbj50a~a9w.md) - Manufacturer Part Number: SMBJ5.0A - Datasheet URL: https://www.littelfuse.com/~/media/electronics/datasheets/tvs_diodes/littelfuse_tvs_diode_smbj_datasheet.pdf.pdf - Manufacturer Name: Littelfuse Inc. - Part Type: Diode **Pins:** - A - K ### EXTTEMP1 — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn~brb.md) - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) - Part Type: Connector - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - Manufacturer Name: JST Sales America Inc. **Pins:** - P1 [pin 1] - P2 [pin 2] ### F1 — [Fuse_1812_4532Metric](https://www.flux.ai/adrian95/fuse18124532metric~yh8.md) - Datasheet URL: https://datasheet.lcsc.com/lcsc/1912111437_Shenzhen-Jinkaisheng-Elec-JK-nSMD150SF_C369553.pdf - Current: 1.5A - Voltage: 8V - Manufacturer Name: Shenzhen Jinkaisheng Elec - Manufacturer Part Number: JK-nSMD150SF **Pins:** - P1 - P2 ### H1 — [MountingHole 7.4mm Pad 3.2mm drill](https://www.flux.ai/adrian95/mountinghole-74mm-pad-32mm-drill~7o1.md) - Manufacturer Part Number: MountingHole_Pad **Pins:** - 1 ### H2 — [MountingHole 7.4mm Pad 3.2mm drill](https://www.flux.ai/adrian95/mountinghole-74mm-pad-32mm-drill~7o1.md) - Manufacturer Part Number: MountingHole_Pad **Pins:** - 1 ### H3 — [Mounting Hole 3.2mm DIN965 Pad](https://www.flux.ai/adrian95/mounting-hole-32mm-din965-pad~aio.md) - Part Type: Connector **Pins:** - Pin_1 [pin 1] ### J2 — [Pin Socket 02x03 2.54mm Vertical](https://www.flux.ai/adrian95/pin-socket-02x03-254mm-vertical~gq.md) - Datasheet URL: https://datasheet.lcsc.com/lcsc/2202082130_Nextron-Nextronics-Engineering-Z-100063200100100_C190817.pdf - Manufacturer Name: Z-100063200100100 - Manufacturer Part Number: Nextron(Nextronics Engineering) - License: https://creativecommons.org/licenses/by/4.0/ - Part Type: Connector **Pins:** - Pin_1 [pin 1] - Pin_2 [pin 2] - Pin_3 [pin 3] - Pin_4 [pin 4] - Pin_5 [pin 5] - Pin_6 [pin 6] ### POWER — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn~brb.md) - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) - Part Type: Connector - Manufacturer Name: JST Sales America Inc. - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf **Pins:** - P1 [pin 1] - P2 [pin 2] ### Q1 — [AO3400A](https://www.flux.ai/adrian95/ao3400a~ug9.md) - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: AO3400A - Datasheet URL: https://media.digikey.com/pdf/Data%20Sheets/Alpha%20&%20Omega/AO3400A_ds.pdf - Manufacturer Name: Alpha & Omega Semiconductor Inc. - Part Type: Transistor **Pins:** - D [pin 3] - G [pin 1] - S [pin 2] ### REMOTE — [Pin Header 01x02 2.54mm Vertical](https://www.flux.ai/jharwinbarrozo/pin-header-01x02-254mm-vertical~4uy.md) - Part Type: Connector - Datasheet URL: https://datasheet.lcsc.com/lcsc/1811151527_JST-Sales-America-RE-H022TD-1190-LF-SN_C160332.pdf - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: RE-H022TD-1190(LF)(SN) - Manufacturer Name: JST Sales America **Pins:** - P1 [pin 1] - P2 [pin 2] ### RX — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn~brb.md) - Part Type: Connector - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) - Manufacturer Name: JST Sales America Inc. - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - P1 [pin 1] - P2 [pin 2] ### TX — [S2B-PH-K-S(LF)(SN)](https://www.flux.ai/adrian95/s2b-ph-k-slfsn~brb.md) - Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Name: JST Sales America Inc. - Part Type: Connector - Manufacturer Part Number: S2B-PH-K-S(LF)(SN) **Pins:** - P1 [pin 1] - P2 [pin 2] ### U1 — [ATTINY841-SSU](https://www.flux.ai/adrian95/attiny841-ssu~xgr.md) - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-8495-8-bit-AVR-Microcontrollers-ATtiny441-ATtiny841_Datasheet-Summary.pdf - Manufacturer Name: Microchip - Manufacturer Part Number: ATTINY841-SSU - Part Type: Microcontroller **Pins:** - ~RESET~/PB3 [pin 4] - AREF/PA0 [pin 13] - GND [pin 14] - PA1 [pin 12] - PA2 [pin 11] - PA3 [pin 10] - PA4 [pin 9] - PA5 [pin 8] - PA6 [pin 7] - PA7 [pin 6] - PB2 [pin 5] - VCC [pin 1] - XTAL1/PB0 [pin 2] - XTAL2/PB1 [pin 3] ### U2 — [EL3H7(B)(TA)-G](https://www.flux.ai/adrian95/el3h7bta-g~gxd.md) - Datasheet URL: https://everlightamericas.com/index.php?controller=attachment&id_attachment=2584 - Manufacturer Part Number: EL3H7(B)(TA)-G - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Name: Everlight Electronics Co Ltd - Part Type: Transistor **Pins:** - P1 [pin 1] - P2 [pin 2] - P3 [pin 3] - P4 [pin 4] ### Y1 — [Crystal SMD 5032 2PIN](https://www.flux.ai/adrian95/crystal-smd-5032-2pin~v9u.md) - Datasheet URL: https://datasheet.lcsc.com/lcsc/2008251032_Murata-Electronics-CSTNE8M00G55A000R0_C341523.pdf - Frequency: 8MHz - Manufacturer Part Number: CSTNE8M00G55A000R0 - Part Type: Oscillator - Manufacturer Name: Murata Electronics **Pins:** - P1 - P2 - P3 - P4 *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/flux/attiny841-bms~e1](https://www.flux.ai/flux/attiny841-bms~e1).* --- *Generated from [https://www.flux.ai/flux/attiny841-bms~e1](https://www.flux.ai/flux/attiny841-bms~e1)*