Cirrus Logic CDB1611-8W - Manual (Page 12)

CDB1611-8W
12 DS978DB4
6. INDUCTOR CONSTRUCTION
The CDB1611-8W includes a critical conduction mode (CRM) boost converter that provides power factor correction
and dimmer compatibility with a constant output current, quasi-resonant flyback stage. The following sections de-
scribe the boost and flyback inductors installed on the CDB1611-8W.
6.1 Boost Inductor
The CS1611 uses an adaptive dimmer compatibility algorithm to control the boost inductor stage, which guarantees
dimmer compatibility operation plus enables flicker-free operation with leading-edge, trailing-edge, and digital dim-
mers (dimmers with an integrated power supply). The boost auxiliary winding is used for zero-current detection
(ZCD) and supplies power to the CS1611.
Figure 7. Boost Inductor Schematic
6.1.1 Electrical Specifications
Characteristics conditions:
• Operating temperature range: -25 °C to +120 °C (including coil heat)
Notes: 7. Measured across pins 1 and 2.
8. Measured across pins 5 and 4.
Parameter Condition Symbol Min Typ Max Unit
Boost Inductor
Primary Inductance
(Note 7) f
resonant
=10kHz, 0.3V at 20°C L
P
6.12 6.8 7.48 mH
Primary DC Resistance (Note 7) t
DCR
=20°C 12 15 18 
Auxiliary DC Resistance (Note 8) 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