Shared Projects by rupin

Often Times, we need a clock signal on digital logic circuits, more often when students in a class are experimenting and learning.

This circuits used a 32.768 kHz crustal and a few frequency divider ICS to generate 12 different clocks of 0.5Hz, 1Hz, 2Hz, 4Hz, 8Hz, 32Hz, 64Hz, 128Hz, 256Hz, 512Hz, 1024Hz, 2048Hz. It plugs directly into a MB102 sized breadboard and borrows power from the headers on the top rail. (Bottom rail headers is for support only)

A 1n4148 diode provides reverse polarity protection. PCB is made with Through Hole Components to be beginner friendly. BOM

1. 1n4148 Diode x1

2. 16v 100uf Electrolytic Capacitor x 1

3. CD4060 x1

4. CD4013 x 1

5. 6.8Mohm resistors x 2

6. 1kohm x 1

7. 330kohm x 1

8. 32.768 kHz crystal x1

9. 33pF ceramic Capacitors x 2

10. 2x6 headers x 2

11. 1x12 headers x 1

12. IC socket 14 pin x1

13. IC socket 16pin x 1

14. 5mm LED ( Red Color) x1

15. 2x1 Header x2

PCB tested and confirmed to be working

Inspired by the TrigBoard by Kevin Darrah, The design uses an ESP8266-01 Module to create a notification/email when the two Pins of the INP header are connected together. This does not have any Low power or Battery integrations, because my use case has 5V DC power available, but not access to charge the device. I have used a capacitor and a BC547 to convert a High to Low transition to create a low pulse. Hence the input will stay engaged, but the notification is only sent once.

This is the V2 version which supports either a CR2032 Battery or a Li Ion Battery. The charger for the Li Ion Battery is onboard.

A blinky badge based on the circuit design from this Youtube video. https://www.youtube.com/watch?v=vA7GH97h4tY&feature=youtu.be

BOM ( CR2032 Version)

• 6x BC847 SOT23 Small Signal Transistor

• 6x 0805 47uF Capacitor

• 6x 0603 10k Resistors

• 6x 0603 220-1k Resistors

• 6x 0603 SMD LED of your choice

• 1x CR2032 SMD Holder

• 1x SMD Slide Switch

BOM ( Li Ion Version)

• 6x BC847 SOT23 Small Signal Transistor

• 6x 0805 47uF Capacitor

• 6x 0603 10k Resistors

• 6x 0603 220-1k Resistors

• 6x 0603 SMD LED of your choice

• 1x Li Ion Battery

• 1x Green 0805 LED to denote charge completion

• 1x 1k 0402 Resistor

• 1x 2k( see Footnote 1) Resistor 0402 for 200mAh Charging current bias.

• 1x Micro USB Connector

• 1x MCP73831 or LTC4054 SOT23 Li Ion battery charger

• 1x SMD Slide Switch

Optional

• 6x 3mm LED

Footnotes

• Please check Charger chip datasheet to match 1C(or less) charging current for your battery.

TPA4056 based Li Ion Battery Charger.

This used a standard USB A Male connector to be charged through a Battery Bank or Wall plug.

BOM

USB_A is USB Male Through Hole Connector

CProg, 0603 resistor 10k (for 130mA charging current) or 3k ( for 400mA charging current). Decide on value of resistor based on 1C charging speedof battery. If in doubt, use 10k.

R1 is 0603 10k pulldown resistor

R2, R3 are LED current limiting resistors, any value between 600-1k ohm should be fine.

CHG is 0805 LED of Red color

STBY is 0805 LED of Blue or Green Color

TPA4056 U1 SOP package charge controller

CAPACITOR-0805 C1 0805 for output filtering 100uF

Project currently does not have reverse polarity protection.

Public project on EASYEDA https://easyeda.com/account/project/setting/basic?project=706c597cf42f46719eed83a5ff0f38fe