CS1630 Datasheet, PDF (5/56 Pages) Cirrus Logic – 2-Channel TRIAC Dimmable LED Driver IC

CS1630/31
2. PIN DESCRIPTION
Boost Zero-current Detect BSTAUX 1
Rectifier Voltage Sense
IAC 2
16 BSTOUT Boost Output Voltage Sense
15 FBAUX
Second Stage Zero-current Detect
Voltage Clamp Current Source CLAMP 3
Source Ground
SGND 4
Source Switch SOURCE 5
I²C Data
SDA 6
I²C Clock
SCL 7
No Connection
NC 8
14 VDD
IC Supply Voltage
13 _GD
Gate Driver
12 _GND
Ground
11 _FBSENSE Second Stage Current Sense
10 eOTP
External Overtemperature Protection
9 SYNC
Second Stage Synchronization
16-lead SOIC
Figure 2. CS1630/31 Pin Assignments
Pin Name Pin #
I/O
BSTAUX
1
IN
IAC
2
CLAMP
3
SGND
4
SOURCE
5
SDA
6
SCL
7
NC
8
SYNC
9
eOTP
10
FBSENSE
11
GND
12
GD
13
VDD
14
FBAUX
15
BSTOUT
16
IN
OUT
PWR
IN
I/O
IN
-
OUT
IN
IN
PWR
OUT
PWR
IN
IN
Description
Boost Zero-current Detect — Boost Inductor demagnetization sensing input for
zero-current detection (ZCD) information. The pin is connected to the PFC boost
inductor auxiliary winding through an external resistor divider.
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.
Voltage Clamp Current Source — Connect to a voltage clamp circuit on the output
of the boost stage.
Source Ground — Common reference current return for the SOURCE pin.
Source Switch — Connected to the source of the boost stage external high-voltage
FET.
I²C™ Data — I²C data.
I²C™ Clock — I²C clock.
No Connection — Leave pin unconnected.
Second Stage Synchronization — A digital synchronization signal that indicates
which channel the controller is signaling for each gate switching period.
External Overtemperature Protection — Connect an external NTC thermistor to
this pin, allowing the internal A/D converter to sample the change to NTC resistance.
Second Stage Current Sense — The current flowing in the second stage FET is
sensed across a resistor. The resulting voltage is applied to this pin and digitized for
use by the second stage computational logic to determine the FET's duty cycle.
Ground — Common reference. Current return for both the input signal portion of the
IC and the gate driver.
Gate Driver — Gate drive for the second stage power FET.
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 transistor.
Second Stage Zero-current Detect — Second stage inductor sensing input. The
pin is connected to the second stage inductor’s auxiliary winding through an external
resistor divider.
Boost Output Voltage Sense — A current proportional to the boost output is fed
into this pin. The current is measured with an A/D converter.
DS954F2
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