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FSAB20PH60 Rev. A
FSAB20PH60 Smart Power Module for Partial Switching Converter
Note:
1. To avoid malfunction, the wiring of each input should be as short as possible. (less than 2-3cm)
2. V
FO
output is open collector type. This signal line should be pulled up to the positive side of the 5V power supply with approximately 4.7kΩ resistance. Please refer to Figure 9.
3. V
FO
output pulse width should be determined by connecting an external capacitor(C
FOD
) between C
FOD
(pin7) and COM(pin2). (Example : if C
FOD
= 33 nF, then t
FO
= 1.8ms
(typ.)) Please refer to the note 6 for calculation method.
4. Input signal is High-Active type. There is a 3.3k
Ω resistor inside the IC to pull down each input signal line to GND. When employing RC coupling circuits, set up such RC couple
that input signal agree with turn-off/turn-on threshold voltage.
5. To prevent errors of the protection function, the wiring around R
SC
, R
F
and C
SC
should be as short as possible.
6. In the over current protection circuit, please select the R
F
C
SC
time constant in the range 3~4 µs.
7. Each capacitors should be mounted as close to the pins as possible.
8. Relays are used at almost every systems of electrical equipments of home appliances. In these cases, there should be sufficient distance between the CPU and the relays.
9. Internal NTC thermistor can be used for monitoring the case temperature and protecting the device from the overheating operation. Please select an appropriate resistor R
TH
according to the application. For example, use R
TH
=4.7kΩ that will make the voltage across RTH to be 2.5V at 85°C of the case temperature.
10. This PSC module is not designed for the internal IGBT to be turned on when the current is flowing through the input reactor L
AC
. Otherwise, there will be large reverse recov-
ery current that makes considerably large turn-on switching loss of IGBT, which may destroy the internal IGBTs.
11. Please use an appropriate shunt resistor R
SH
to protect the intenal IGBT from the overcurrent operation. For example, if the IGBT current has to be protected below 25A, then
use 20m
Ω resistor of R
SH
. When selecting protecting current level, please consider the variation and tolerance of external components. Moreover, the shunt resistor path from
N
R
and N
S
to N
D
and ground that is connected to COM of the internal drive IC, should be thick and short in order to minimize the stray inductance that may generate improper
switching of the module.
Figure 11. Application Circuit
Inverter
+5V
V
ac
CSC
CFOD
VFO
IN(S)
IN(R)
COM
VCC
OUT(S)
OUT(R)
NTC
Thermistor
Q1 Q2
D1
D3
D2
D4
V
TH
R
TH
C
SC
C
FOD
V
FO
IN
(S)
IN
(R)
COM
VCC
P
R
S
R
N
D
N
R
N
S
PSC Module, FSAB20PH60
Microcontroller
or DSP
Gate S
Gate R
Fault
Temperature
Current
+5V
1nF
100Ω
1nF
C
FOD
R
TH
100µF
1µF
4.7kΩ
0.1µF
R
F
C
SC
R
SH
L
AC
