Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Coin cell that can deliver 10ma

Status
Not open for further replies.
J

Jester

Full Member level 6
Joined
Aug 18, 2012
Messages
377
Helped
7
Reputation
14
Reaction score
7
Trophy points
1,298
Location
.
Activity points
4,754
I'm looking for a coin cell that can provide at least 10ma while maintaining output voltage above 2.8V

If you look at the voltage vs. current profile for a typical coin cell (see CR2450), you will see even if they have a substantial ma/hr rating the continuous standard load specification is very low for example 200uA.

Any suggestions?
 

Most "coin" cells are designed for a low-current load. With 10 mA load, most coin cells will discharge rapidly.
Find a "rechargeable" coin cell,or use an AA or AAA alkaline cell (two), they can live longer with 10-mA load.
 

No room for AA or AAA
 

Why are you using a tiny weak little battery? The datasheet of the CR2450 Lithium coin cell from Energizer rates it with a 0.39mA load. It shows it brand new with an internal resistance of about 16 ohms when its load is 9mA so its 3V drops to 2.86V. They show a 9mA load for 2 seconds 12 times per day. Its internal resistance quickly rises to 120 ohms then with a 9mA load its 3V drops to only 1.92V.
 

Audioguru said:
Why are you using a tiny weak little battery? The datasheet of the CR2450 Lithium coin cell from Energizer rates it with a 0.39mA load. It shows it brand new with an internal resistance of about 16 ohms when its load is 9mA so its 3V drops to 2.86V. They show a 9mA load for 2 seconds 12 times per day. Its internal resistance quickly rises to 120 ohms then with a 9mA load its 3V drops to only 1.92V.
Click to expand...

Existing product that uses a CR2450 cell, the company now wants to squeeze additional circuitry (bluetooth module that will be used very intermittently) into the same footprint and enclosure. I can fit the components, however current requirements will be about 10ma for short bursts while the radio is active. No room for a larger battery.
 

Jester said:
Existing product that uses a CR2450 cell, the company now wants to squeeze additional circuitry (bluetooth module that will be used very intermittently) into the same footprint and enclosure. I can fit the components, however current requirements will be about 10ma for short bursts while the radio is active. No room for a larger battery.
Click to expand...

Add a capacitor?
 

Yes, the capacitor supplies the short bursts of 10mA and the battery slowly charges it.
Of course the battery life will be less than it was before this Bluetooth module was added.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top