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■NOTES ON USE (Continued)

6)

Even in the PWM control, the intermittent operation occurs and the ripple voltage becomes higher, when the minimum On

Time is faster than 85ns (typ.) as well as the dropout voltage is large and output current is small.

7)

The ripple voltage could be increased when switching from discontinuous conduction mode to continuous conduction mode

and at switching to 100% Duty cycle. Please evaluate IC well on customer’s PCB.

8)

The PWM/PFM auto series may cause superimposed ripple voltage by continuous pulses if used in high temperature and no

is lower than 7.5kΩ. Please refer to the

9)

If the voltage at the EN/SS Pin does not start from 0V but it is at the midpoint potential when the power is switched on, the

soft start function may not work properly and it may cause the larger inrush current and bigger ripple voltages.

10) Torex places an importance on improving our products and their reliability. We request that users incorporate fail-safe designs

and post-aging protection treatment when using Torex products in their systems.

11)

Instructions of pattern layouts

The operation may become unstable due to noise and/or phase lag from the output current when the wire impedance is

(2) Please mount each external component as close to the IC as possible.

Please place the external parts on the same side of the PCB as the IC, not on the reverse side of the PCB and elsewhere.

(3) Wire external components as close to the IC as possible and use thick, short connecting traces to reduce the circuit

Impedance.

(4) Make sure that the GND traces are as thick as possible, as variations in ground potential caused

by high ground currents at the time of switching may result in instability of the IC.

(5) Please note that internal driver transistors bring on heat because of the load current and ON resistance

of High side driver transistor, Low side driver transistor. Please make sure that the heat is dissipated properly,

especially at higher temperatures.

Lx

PG

FB

GN D

EN/SS

L

(a)TVS

(1)C

IN1

(c)Reverse-Touching

Prot ection Diode

(b)SBD

C

IN2