TSM1011 STMicroelectronics, TSM1011 Datasheet - Page 6

• Manufacturer Part Number: TSM1011
• Description: Constant Voltage and Constant Current Controller
• Manufacturer: STMicroelectronics

TSM1011
6
The voltage-control transconductance operational
amplifier can be fully compensated. Both its
output and negative input are directly accessible
for external compensation components.
An example of a suitable compensation network is
shown in
C
Fig. 4: Schematic of compensation network
7
Under start-up or short-circuit conditions the
TSM1011 is not provided with a high enough
supply voltage. This is due to the fact that the chip
has its power supply line in common with the
power supply line of the system.
Therefore, the current limitation can only be
ensured by the primary PWM module, which
should be chosen accordingly.
If the primary current limitation is not considered
to be precise enough for the application, then a
sufficient supply for the TSM1011 has to be
ensured under all conditions. This means that it is
6/9
cv1
COMPENSATION
START UP AND SHORT CIRCUIT CONDITIONS
=2.2nF and a resistor R
DS
Vcc
Figure 5
CS
+
. It consists of a capacitor
+
R4
10K
R5
1K
cv1
Rsense
1
5
3
Vsense
=22K in series.
Cv+
Cc+
IL
Rlimit
Cc-
Vref
Ric2
1K
Vcc
CV
CC
28V
TSM1011
Gnd
Ric1
22K
The current-control transconductance operational
amplifier can be fully compensated. Both of its
output and negative input are directly accessible
for external compensation components.
An example of a suitable compensation network is
shown in
C
necessary to add some circuitry to supply the chip
with a separate power line. This can be achieved
in numerous ways, including an additional winding
on the transformer.
Cv-
Out
ic1
=2.2nF and a resistor R
4
7
R3
100
Figure 5
Rvc1
22K
Cic1
2.2nF
. It consists of a capacitor
2.2nF
Cvc1
D
ic1
R2
R1
=22K
Compensation
+
IL
in series.
OUT+
OUT-