Low-loss e-STARTER demonstration board for compressor
Features
■ Suitable for refrigerator and freezer
compressor applications
■ Reduces PTC resistor power losses
Description
The e-STARTER demonstration board represents
an innovative solution patented by
STMicroelectronics to reduce the power losses
caused by positive temperature coefficient (PTC)
resistors in compressor starter circuits.
The solution features an ACST6 AC switch device
which is used to turn off the PTC current after
motor start-up. It should be noted that the
traditional PTC is still used in the electronic
starter circuit, as it increases the safety of the
circuit in cases of AC switch short-circuit or diode
mode failure (ref. EN60335-1).
STEVAL-IHT003V1
starter circuits based on the ACST6
Data Brief
STEVAL-IHT003V1
The design allows the starter standby losses to be
reduced from (typ) 2.5 W to 380 mW for 230 V
applications, or 2.5 W to 40 mW for 100 V
applications.
Because this board is not a “plug and play”
solution, prior to using the board with a
compressor the PTC behavior must be checked
(especially VPTC1 & VPTC2 levels), and different
R4 resistor value may be required.
July 2008 Rev 1 1/4
For further information contact your local STMicroelectronics sales office.
www.st.com
4
Schematic diagram STEVAL-IHT003V1
1 Schematic diagram
Figure 1. e-STARTER circuit schematic
C1
10 nF
BZX55C
A
1 MΩ
V
C2
V
AM00202
D1
1N4007
R3
R4
30 kΩ
510 kΩ
R5
Q1
PMBT2907A
D2
C1
10 kΩ
DZ1
C
Q2
R8
1N4148PMBT2222A
R7
C2
10 nF
(1)
C3
x nF
GND
220 Ω
1
3
0
R2
470 kΩ
R1
620 Ω
1
D7
+
4
1
3
DF06
2
R6
1
3
MMBF170
M1
T2
X0205N
3
–
22 nF
C4
47 Ω
A
I
ACST6
T1
AK
V
J16
START
J17
1. Capacitor C3 is not soldered on the board, but can be added in order to evaluate its impact on board
immunity.
2/4
PTC
J18
RUN