Owner manual

CS1615/16
DS961F1 3
2. PIN DESCRIPTION
Figure 2. CS1615/16 Pin Assignments
16 -lead SOIC and TSSOP
16 Zero-current DetectFBAUX
15
No ConnectNC
14
IC Supply VoltageVDD
13 GD Gate Drive
10 eOTP External Overtemperature Pr otection
11 FBSENSE Fl yback Current Sense
12 GND Gr ound
9 LED Load Curr entCTRL2
No Connect NC
1
2
IACRectifier Voltage Sense
3
Voltage Clamp Current Source CLAMP
4 SGNDSource Gr ound
5 Source Switch SOURCE
6 NCNo Connect
7 No Connect NC
8 CTRL1Dimmer Hold Current
Pin Name Pin # I/O
Description
NC 1INNo Connect — Leave pin unconnected.
IAC 2IN
Rectifier Voltage Sense — A current proportional to the rectified line voltage is fed
into this pin. The current is measured with an A/D converter.
CLAMP 3OUT
Voltage Clamp Current Source — Connect to a voltage clamp circuit on the
source-switched dimmer-compatibility circuit.
SGND 4PWRSource Ground — Common reference current return for the SOURCE pin.
SOURCE 5IN
Source Switch — Connected to the source of the source-switched external high-volt-
age FET.
NC 6INNo Connect — Connect this pin to VDD using a 47k pull-up resistor.
NC 7INNo Connect — Connect this pin to VDD using a 47kpull-up resistor.
CTRL1 8IN
Dimmer Hold Current — Connect a resistor to this pin to set the minimum input cur-
rent being pulled by the flyback/buck-boost stage.
CTRL2 9INLED Load Current — Connect a resistor to this pin to set the LED current.
eOTP 10 IN
External Overtemperature Protection — Connect an external NTC thermistor to this
pin, allowing the internal A/D converter to sample the change to NTC resistance.
FBSENSE 11 IN
Feedback Current Sense — The current flowing in the power FET is sensed across a
resistor. The resulting voltage is applied to this pin and digitized for use by the compu-
tational logic to determine the FET's duty cycle.
GND 12 PWR
Ground — Common reference. Current return for both the input signal portion of the
IC and the gate driver.
GD 13 OUT Gate Drive — Gate drive for the power FET.
VDD 14 PWR
IC Supply Voltage — Connect a storage capacitor to this pin to serve as a reservoir
for operating current for the device, including the gate drive current to the power tran-
sistor.
NC 15 - No Connect — Leave pin unconnected.
FBAUX 16 IN
Zero-current Detect — Connect to the flyback/buck-boost inductor auxiliary winding
for demagnetization current zero-crossing detection.