STEVAL-ISA033V1 STMicroelectronics, STEVAL-ISA033V1 Datasheet - Page 13
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STEVAL-ISA033V1
Manufacturer Part Number
STEVAL-ISA033V1
Description
BOARD EVAL L5991/STP12NK80Z
Manufacturer
STMicroelectronics
Type
Supervisory Circuitsr
Specifications of STEVAL-ISA033V1
Main Purpose
AC/DC, Primary Side
Outputs And Type
3, Isolated
Power - Output
55W
Voltage - Output
13.8V, 3.8V, 25V
Current - Output
3A, 350mA, 200mA
Voltage - Input
88 ~ 300VAC
Regulator Topology
Flyback
Board Type
Fully Populated
Utilized Ic / Part
L5991, STP12NK80Z
Input Voltage
88 V to 300 V
Output Voltage
3.8 V to 25 V
Product
Power Management Modules
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Frequency - Switching
-
Lead Free Status / Rohs Status
Lead free / RoHS Compliant
For Use With/related Products
L5991, STP12NK80Z
Other names
497-8226
STEVAL-ISA033V1
STEVAL-ISA033V1
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
STEVAL-ISA033V1
Manufacturer:
STMicroelectronics
Quantity:
1
Figure 30. Disable (Latched).
connecting DC-LIM to VREF (half duty cycle op-
tion), Dx will be set approximately at:
Figure 31. Half duty cycle option.
Figure 32. Standby function internal schematic and operation.
DISABLE
SIGNAL
C
FB
DIS
5
2.5
D
x
+
-
14
2.5V
2 R
COMP
6
V15=GND
V5=V13=GND
V15=VREF
V5=V13=GND
+
-
R
T
2.5/4
T
260
STANDBY BLOCK
t c
t c
+
-
2R
R
13
11
ISEN
UVLO
LEVEL SHIFT
D
R
+
-
10V
Q
DISABLE
STANDBY
D97IN502
t
d
t
d
R
DRIVER
and the output switching frequency will be halved
with respect to the oscillator one because an in-
ternal T flip-flop (see block diagram) is activated.
Fig. 31 shows the operation.
The half duty cycle option speeds up the dis-
charge of the timing capacitor C
duty cycles as close to 50% as possible) so the
oscillator frequency - with the same timing compo-
nents will be slightly higher.
Pin 16. S-BY (Standby Function). The resistor R
along with R
oscillator in normal operation (f
as the STANDBY signal is high, the pin is inter-
nally connected to the reference voltage VREF by
a N-channel FET (see fig. 32), so the timing ca-
pacitor C
the STANDBY signal goes low the N-channel FET
is turned off and the pin becomes floating. R
D97IN498
16
4
2
OUT
VREF
ST-BY
RCT
R
B
T
is charged through R
V10
V10
V2
V2
A
R
C
A
, sets the operating frequency of the
T
STANDBY
HIGH
LOW
D
D
X
X
D97IN752B
=
=
2 ·t c + t d
t c + t d
t c
t c
2.5V
V
T1
osc
L5991 - L5991A
V
4V
T2
T
A
). In fact, as long
(in order to get
and R
V
COMP
B
. When
13/23
B
B
is
,