VIPer22A-E, VIPer22ADIP-E, VIPer22AS-E
Operations
4
Operations
4.1
Rectangular U-I output characteristics
Figure 4.
Rectangular U-I output characteristics for battery charger
DCOUT
R1
T1
C1
C2
D3
D2
D1
T2
F1
C3
AC IN
D4
ISO1
U1
C4
VDD
DRAIN
FB
C5
CONTROL
C6
SOURCE
VIPerX2A
C7
R2
D5
U2
R3
R4
C9
Vcc
Vref
R5
R6
C8
R8
-
+
+
-
C10
GND
R7
R9
TSM101
R10
GND
A complete regulation scheme can achieve combined and accurate output characteristics.
Figure 4. 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.
Doc ID 12050 Rev 2
7/21
STMICROELECTRONICS [ ST ]
