Summary description

L6732

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Summary description

The controller is an integrated circuit realized in BCD5 (BiCMOS-DMOS, version 5)

fabrication that provides complete control logic and protection for high performance step-

down DC-DC and niPoL converters.

It is designed to drive N-channel MOSFETs in a synchronous rectified buck topology. The

output voltage of the converter can be precisely regulated down to 600 mV with a maximum

tolerance of ±0.8 % and it is also possible to use an external reference from 0 V to 2.5 V.

The input voltage can range from 1.8 V to 14 V, while the supply voltage can range from

4.5 V to 14 V. High peak current gate drivers provide for fast switching to the external power

section, and the output current can be in excess of 20 A. The PWM duty cycle can range

conversions with very low duty cycle at high switching frequency. The device provides

voltage-mode control that includes a selectable frequency oscillator (250 kHz or 500 kHz).

The error amplifier features a 10 MHz gain-bandwidth-product and 5 V/µs slew-rate that

permits to realize high converter bandwidth for fast transient response. The device monitors

the need for a current sensing resistor and guaranteeing an effective over-current-protection

in all the application conditions. When necessary, two different current limit protections can

be externally set through two external resistors.

During the soft-start phase a constant current protection is provided while after the soft-start

the device enters in hiccup mode in case of over-current. During the soft-start, the sink

mode capability is disabled in order to allow a proper start-up also in pre-biased output

voltage conditions. After the soft-start the device can sink current. Other features are

power good, master/slave synchronization (with 180° phase shift), over-voltage-protection,

feed-back disconnection and thermal shutdown. The HTSSOP16 package allows the

realization of really compact DC/DC converters.