Please follow below guidance for the inductors design of TPS923655 / TPS923654 / TPS923653 / TPS923652:
Boost Configuration:
In a boost regulator, the inductor DC current can be calculated as:
(1)
(2)
Iout is the current go through the LED load.
The inductor ripple current is calculated as:
(3)
(4)
From (1) - (4), we can get:
K is a coefficient that represents the amount of inductor ripple current relative to the inductor DC current.
Fsw is the switching frequency.
Vout:
(1) If you are using the device in Boost connection, Vout refers to the sum of the forward voltage across LED load.
(2) If you are using the device in Buck-Boost connection, Vout refers to the sum of the forward voltage across LED load plus your maximum input voltage.
For example, in TPS923655 datasheet Section 8.2.1.2, Vin = 12V, Vout = 36V, Iout = 1A, Fsw = 500kHz, choose KIND = 0.6, the calculated inductance is (12*24*12) / (36*0.6*500000*1*36) = 8.9uH.
