Data sheet

10

Rev. 1.0.1, 2013-04-15

TLF51801ELV

Regulator

5.3

Operation Mode

The PWM pulses are voltage controlled. The error amplifier and the PWM comparator are creating the PWM

pulses using the oscillator saw-tooth signal and the feedback voltage. The pulse-width modulation is done so that

the feedback voltage is similar to the reference voltage (1.2 V). To achieve a stable output voltage even under very

low or very high duty cycle conditions a pulse skipping mode is implemented. When the minimum off time for the

up-side gate is reached (boundary between dark grey area and light grey area in Figure 6), the TLF51801ELV

operates in pulse skipping mode for high duty cycle. This operation mode is typically used with low supply voltages

for very low dropout operation. If the minimum on time for the up-side gate is reached (boundary between dark

grey area and light grey area in Figure 6) the TLF51801ELV operates in pulse skipping mode for low duty cycle.

Figure 6

Operation Mode