VIPer22ADIP/ VIPer22AS - E

Operations

Rev1

7/20

4

Operations

4.1

Rectangular U-I Output Characteristics

Figure 3.

Rectangular U-I output characteristics for battery charger

A complete regulation scheme can achieve combined and accurate output characteristics.

Figure 3. presents a secondary feedback through an optocoupler driven by a TSM101. This

device offers two operational amplifiers and a voltage reference, thus allowing the regulation

of both output voltage and current. An integrated OR function performs the combination of

the two resulting error signals, leading to a dual voltage and current limitation, known as a

rectangular output characteristic. This type of power supply is especially useful for battery

chargers where the output is mainly used in current mode, in order to deliver a defined

charging rate. The accurate voltage regulation is also convenient for Li-ion batteries which

require both modes of operation.

4.2

design to achieve various behaviors. In Figure 3 on page 7 a forward configuration has been

chosen to supply the device with two benefits:

T1

D3

C5

C4

D4

C3

T2

F1

C1

C10

-

+

-

+

Vref

Vcc

GND

U2

TSM101

R6

R9

R10

R4

C9

R7

R5

R8

C8

R3

ISO1

D2

D5

R2

C7

R1

C2

D1

FB

VDD

DRAIN

SOURCE

CONTROL

U1

VIPerX2A

C6

AC IN

DCOUT

GND