AN4324

STC3115 selection guide

DocID024963 Rev 2.0

5/31

2

STC3115 selection guide

Two versions, in two different packages, of the STC3115 device currently exist. They are:

1.

STC3115AIJT / STC3115AIQT

2.

STC3115IJT / STC3115IQT

Either version can be selected to plug onto the application.

2.1

STC3115 version selection

The STC3115 can lend its functionalities to different battery types with different voltage

ranges. Depending on the battery voltage, either the STC3115AIJT / STC3115AIQT or the

STC3115IJT / STC3115IQT can be selected.

Table 1: STC3115 version selection

STC3115 version

Battery voltage (typ)

Battery voltage (max)

STC3115AIJT / STC3115AIQT

3.7 V

4.2 V

STC3115IJT / STC3115IQT

3.8 V

4.35 V

The STC3115 behavior is the same with the different versions but the device uses a

different initial internal open circuit voltage (OCV) curve to track the battery state of charge.

The table below describes the internal OCV curve of each STC3115 version.

Table 2: STC3115 internal OCV curve references

State of charge (%)

STC3115AIJT / STC3115AIQT

STC3115IJT / STC3115IQT

100

4.176

4.313

90

4.076

4.197

80

3.991

4.088

70

3.929

3.990

65

3.899

3.953

60

3.863

3.914

50

3.802

3.825

40

3.778

3.790

30

3.761

3.770

25

3.747

3.761

20

3.721

3.743

15

3.695

3.710

10

3.658

3.675

6

3.618

3.651

3

3.541

3.571

0

3.300

3.300