Cirrus Logic CRD1611A-8W - Manual (Page 14)

CRD1611A-8W
14 DS1014RD3
7. INDUCTOR CONSTRUCTION
The CRD1611A-8W includes a critical conduction mode (CRM) boost converter that provides power factor correc-
tion and dimmer compatibility with a constant output current, quasi-resonant flyback stage. The following sections
describe the boost and flyback inductors installed on the CRD1611A-8W.
7.1 Boost Inductor
The CS1611A uses an adaptive dimmer compatibility algorithm to control the boost inductor stage, which guaran-
tees dimmer compatibility operation plus enables flicker-free operation with leading-edge, trailing-edge, and digital
dimmers (dimmers with an integrated power supply). The boost auxiliary winding is used for zero-current detection
(ZCD) and supplies power to the CS1611A.
7.1.1 Electrical Specifications
Characteristics conditions:
• Operating temperature range: -25 °C to +120 °C (including coil heat)
Notes: 1. Measured across pins 1 and 2
2. Measured across pins 5 and 4
Parameter Condition Symbol Min Typ Max Unit
Boost Inductor
Primary Inductance (Note 1) f
resonant
=10kHz, 0.3V at 20°C L
P
6.12 6.8 7.48 mH
Primary DC Resistance (Note 1) t
DCR
=20°C 12 15 18 
Auxiliary DC Resistance (Note 2) t
DCR
=20°C 0.84 1.05 1.26 
2
1
5
4
400T
#37AWG
(0.12mm)
22T
#37 AWG
(0.12 mm)
Primary
Auxillary
Figure 10. Boost Inductor Schematic