ST STCC08 User Manual
Features
■ 3.3 V and 5 V power supply compatible
■ ACS, ACST, TRIAC compatible
■ Gate driver output: 28 mA max sink current
■ Adjustable gate drive current
■ Sense the AC switch voltage in both AC line
polarities
■ Diode mode failure detection for solid state AC
switches
■ Short circuit failure detection for AC switches,
relays, electromechanical switches
■ Open AC switch detection for AC switches,
relays, electromechanical switches
■ SO-8 SMD package
STCC08
AC switch failure mode detector
SO-8
Applications
■ Home appliances
■ ACS, ACST, TRIAC drive
■ AC switch failure modes detection
■ Zero voltage synchronization
Benefits
■ Enable appliances to meet IEC 60335-1 and
IEC 60730-1 standards
■ Enable appliances to meet IEC 61000-4-4
standard
■ Eliminates high DC current in inductive load, by
detecting the diode mode failure
■ Improve system safety monitoring open switch
failure with critical loads such as door locks
■ Enable MCU to sense all AC switch failure
modes and protect the appliance
■ Less MCU pin allocated to AC failure detection
multiple STCC08 designed with resistor
dividers uses one I/O
■ Easy to drive with MCU directly connected or
through an opto coupler
■ Highly compact with integrated solution in SMD
version
Description
The STCC08 is an AC switch failure mode
detector and an AC power switch driver. It drives
the AC switch and informs the MCU of switch
failure. The MCU takes the appropriate actions to
put the system in a secure state.
Diode-mode, short circuit detection and open
switch in both AC line polarities are detected.
The STCC08 helps home appliances to meet the
IEC 60335-1 safety standard.
The STCC08 can be easily interfaced to an MCU
with its CMOS input AC switch driver and CMOS
compatible output for the failure mode detector.
March 2008 Rev 1 1/13
www.st.com
13
Characteristics STCC08
1 Characteristics
Figure 1. Circuit block diagram
G
V
CC
AC
POWER SWITCH
SIGNAL SHAPING
Table 1. Circuit pin descriptions
GATE DRIVER
+
-
AVF DRIVER
Symbol Type Description
IN SIGNAL Logic AC switch drive
AVF SIGNAL Alternating voltage feedback: AC switch status output
AC SIGNAL AC switch status sense input
V
CC
POWER Positive power supply
G SIGNAL AC switch gate driver output
IN
R
AVF
GND
IG
R
IG
SIGNAL AC switch gate current setting
GND POWER Power supply reference
Figure 2. Pin layout (top view)
IN
IN
AVF
AVF
N/C
N/C
AC
AC
2/13
GND
GND
R
R
IG
IG
G
G
V
V
CC
CC
STCC08 Characteristics
Table 2. Pin allocations
Pin # Name Description
1 IN Logic AC switch drive
2 AVF Alternating voltage feedback: AC switch status output
3 N/C Not connected
4 AC AC switch status sense input
5V
CC
6 G AC switch gate driver output
Positive power supply
7R
IG
AC switch gate current setting
8 GND Power supply reference
Table 3. Absolute ratings (T
= 25 °C unless otherwise stated, respect to GND)
amb
Symbol Pin Parameter name and conditions Value Unit
V
V
V
I
I
CC
IN
I
G
AC
AVF
AVF
V
CC
IN Switch activation voltage -0.3V to VCC +0.3 V
G Sunk driver current 30 mA
AC Input sense current peak 2.2 mA
AVF Alternative feedback voltage -0.3 to V
AVF Maximum feedback current 5 mA
Power supply voltage 0 to 6 V
+0.3 V
CC
Junction temperature range -20 to 125 °C
T
J
Table 4. Recommended operating conditions
All
Storage junction temperature range -40 to 150 °C
Symbol Pin Parameter name and conditions Value Unit
V
CC
I
G
R
IG
V
CC
G Max. sunk driver gate current 28 mA
RIG Gate current setting resistor 30 Ω
Power supply voltage respect to GND 2.97 to 5.5 V
Detector resistance for AC line = 120 V 100 kΩ
R
AC
AC
Detector resistance for AC line = 230 V 300 kΩ
R
SHUNT
T
AMB
T
J
HV biasing resistance for AC line = 120 V 100 kΩ
HV biasing resistance for AC line = 230 V 300 kΩ
All Operating ambient temperature range -20 to 85 °C
All Operating junction temperature range -20 to 125 °C
3/13
Characteristics STCC08
Table 5. Electrical characteristics
Symbol Pin Name Conditions Min Typ Max Unit
Switch drive (respect to GND, Tj=25 °C unless otherwise specified, RIG=30 Ω)
I
QUIESCENTVCC
V
ON
V
OFF
Quiescent current IN = GND 2 mA
On-state switch
IN
activation voltage
Off-state switch
IN
release voltage
0.7*V
CC
0.3*V
CC
V
V
I
IN
I
G
I
AC
V
OH
IN Input drive current Vin > V
G Gate drive current Vin > V
on
on
20 28 mA
AC Detection threshold 82 236 µA
Status output (respect to GND, T
Minimum output
AVF
voltage
=25 °C unless otherwise specified)
j
= 50 µA 0.7*V
I
AVF
I
AVF
= 50 µA
CC
(CMOS Compatible)
V
OL
AVF Maximum drop voltage
I
AVF
= 5 mA
(Opto-transistor
50 µA
0.3*V
CC
1V
compatible)
Table 6. Thermal resistance
Symbol Parameter name and conditions Value Unit
R
TH (j-a)
Table 7. System related electromagnetic compatibility ratings
SMD Thermal resistance Junction to Ambient 140 °C/W
Symbol Node Pin Parameter name and conditions Value Unit
ESD protection, IEC 61000-4-2, per input, against air
V
CC
discharge
Neutral
V
ESD
Gate through ACS; ESD protection, IEC 61000-4-2, pin to
ground, against air discharge
±8 kVG
V
V
Line AC
V
ESD
Neutral V
Neutral
V
PPB
Line AC
1. System oriented test circuits - see Application note AN2716
Alternating current through R
IEC 61000-4-2, pin to ground, against air discharge
ESD protection, IEC 61000-4-2, pin to ground, for contact
CC
discharge
V
Total Peak Pulse Voltage Burst, IEC 61000-4-4
CC
Gate through ACS; Total Peak Pulse Voltage Burst, IEC
G
61000-4-4
(1)
(1)
Alternating current through RAC; Total Peak Pulse Voltage
Burst, IEC 61000-4-4
4/13
(1)
= 300 kΩ; ESD protection,
AC
±6 kV
(1)
±4 kV