Varta 63094, Technical Handbook

Page: 29 / 45

Batt
ery cell
COINPOWER | 29
6.3 Protection Circuit Module (PCM)
The Protection Circuit Module (PCM) is a device to
protect a battery against the risk of abnormal events
such as over-discharging or short circuits. This is
mandatory for all Lithium cells.
A PCM is not only used to protect the cells and
applications from excessive discharge and recharge
current, but also to maintain the nominal operating
conditions for the cell and battery pack.
A CoinPower battery must be operated with a PCM
which provides the following protection functions:
• Over-charge protection
• Over-discharge protection
• Over-current protection
• Short circuit protection
• Optional additional functions: Over-temperature
protection, ESD protection, Code identification,
Power management, Fuel gauge
Safety Tests
Recommended PCM for CoinPower Series:
• SG Micro (SGM41100V)
• Ricoh (R5613L)
Other suitable PCM:
• Seiko (S8211CAY, S8200A)
• Mitsumi (MM3077 LY, MM2511 K56)
• Texas Instruments (BQ 29700, BQ 29707)
• Diodes (AP9211)
The schematic for using a PCM for the CoinPower is quite simple, just
a few external components are necessary to build a fully functional
safety circuit. Below is an example for the SEIKO 8211 CAY:
Voltage range for PCM and Charger
Example for the SEIKO 8211
FIG. 23
COINPOWER | SAFETY