DocID18279 Rev 5

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ST1CC40

Functional description

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The error amplifier output is compared with the inductor current sense information to

perform PWM control.

5.5

Inhibit

The inhibit block disables most of the circuitry when the INH input signal is low. The current

drawn from the input voltage is 6 µA typical in inhibit mode.

5.6

Thermal shutdown

The shutdown block generates a signal that disables the power stage if the temperature of

the chip goes higher than a fixed internal threshold (150 ± 10 °C typical). The sensing

element of the chip is close to the PDMOS area, ensuring fast and accurate temperature

detection. A 15 °C typical hysteresis prevents the device from turning ON and OFF

continuously during the protection operation.

Table 5. Uncompensated error amplifier characteristics

Description

Value

Transconductance

250 µS

Low frequency gain

96 dB

195 pF

70 K

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