STCS1APHR STMicroelectronics, STCS1APHR Datasheet - Page 12

• Manufacturer Part Number: STCS1APHR
• Description: IC LED DRIVR PWM CONTROL PWRSO-8
• Manufacturer: STMicroelectronics
• Type: PWM Controlr

Specifications of STCS1APHR

• Constant Current: Yes
• Topology: PWM
• Number Of Outputs: 1
• Internal Driver: Yes
• Type - Primary: Automotive
• Type - Secondary: White LED
• Voltage - Supply: 4.5 V ~ 40 V
• Mounting Type: Surface Mount
• Package / Case: PowerSO-8
• Operating Temperature: -40°C ~ 125°C
• Current - Output / Channel: 1.5A
• Internal Switch(s): Yes
• High Level Output Current: 1500 mA
• Operating Supply Voltage: 4.5 V to 40 V
• Maximum Supply Current: 3 uA
• Maximum Operating Temperature: + 150 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• For Use With: 497-8264 - BOARD EVAL BASED ON STCS1497-5960 - BOARD DEMO FOR STCS1P
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Frequency: -
• Efficiency: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 497-6915-2; STCS1APHR

8
8.1
Figure 15. Reverse polarity condition
8.2
12/19
Application information
Reverse polarity protection
STCS1A must be protected from reverse connection of the supply voltage. Since the current
sunk from V
protect the chip. Care must be taken for the whole application circuit, especially for the
LEDs, in fact, in case a negative voltage is applied between V
voltage will be applied to the LED string that must have a total breakdown voltage higher
than the negative applied voltage in order to avoid any damage.
Thermal considerations
The STCS1A is able to control a LED current up to 1.5 A and able to sustain a voltage on
the drain pin up to 40 V. Those operating conditions are however limited by thermal
constraints, the thermal resistances shown in the
in particular R
circuit board under the pad. DFN8 and PowerSO-8 have an exposed die attach pad which
enhances the thermal conductivity enabling high power application.
The power dissipation in the device can be calculated as follow:
P
basing on this and on the thermal resistance and ambient temperature, the junction
temperature can be calculated as:
T
A typical application could be:
J
D
= R
– Input voltage: 12 V;
– 3 white LEDs with an typical V
= (V
thJA
DRAIN
x P
CC
- V
thJA
D
pin is in the range of 450 µA a small diode connected to V
V
V
V
V
+ T
IN
IN
IN
IN
FB
depends on the copper area and the number of layers of the printed
A
) x I
BAT46
BAT46
or similar
or similar
or similar
or similar
+
+
+
+
LED
+ (V
CC
x I
CC
F
=3.6 V;
PWM
PWM
PWM
PWM
EN
EN
EN
EN
V
V
V
V
)
CC
CC
CC
CC
DISC
DISC
DISC
DISC
SLOPE
SLOPE
SLOPE
SLOPE
Thermal data
GND
GND
GND
GND
DRAIN
DRAIN
DRAIN
DRAIN
FB
FB
FB
FB
IN
section are the typical ones,
and GND, a negative
CC
is able to