Cirrus Logic CRD1680-7W - Manual (Page 17)

CRD1680-7W
DS1017RD3 17
7. INDUCTOR CONSTRUCTION
The CS1680 integrates a continuous conduction mode (CCM) boost converter that provides transformer compati-
bility and dimmer compatibility with a constant output current buck stage. The following sections describe the boost
and buck inductors installed on the CRD1680-7W.
7.1 Boost Inductor
The CS1680 uses an adaptive digital algorithm to control the boost stage and dimmer compatibility operation mode,
which enables flicker-free operation down to 5% output current with leading-edge and trailing-edge dimmers. Boost
inductor L1 is selected to be a standard TAIYO YUDEN power inductor.
7.1.1 Electrical Specifications
Characteristics conditions:
• Operating temperature range: -25 °C to +125 °C (including coil heat)
Notes: 1. Measured across pins 1 and 2
7.2 Buck Inductor
The CS1680 buck stage is a constant current-regulated DC-DC converter capable of delivering the highest possible
efficiency with constant current output while minimizing line frequency ripple. Buck inductor L2 is selected to be a
standard TAIYO YUDEN power inductor.
7.2.1 Electrical Specifications
Characteristics conditions:
• Operating temperature range: -25 °C to +125 °C (including coil heat)
Notes: 1. Measured across pins 1 and 2
Parameter Condition Symbol Value Unit
TAIYO YUDEN Boost Inductor #NRS8040T150MJGJ
Inductance (Note 1) f
measured
=100kHz 15 (±20%) H
DC Resistance (Note 1) Maximum 0.065 
Saturation Current Rated Current 2900 mA
Parameter Condition Symbol Value Unit
TAIYO YUDEN Buck Inductor #NR6045T470M
Inductance (Note 1) f
measured
=100kHz 47 (±20%) H
DC Resistance (Note 1) t
DCR
=20°C 0.286 
Saturation Current Rated Current 1300 mA