TLE8366

Module Oscillator

Data sheet

13

Rev. 1.0, 2009-05-18

7

Module Oscillator

7.1

Description

The oscillator supplies the device with a constant frequency. The power switch will be switched on and off with a

constant frequency. The duty-cycle is derived from this frequency and some safety functions are synchronized to

this frequency.

The internal sawtooth signal used for the PWM generation has an amplitude proportional to the input supply

voltage (feedforward).

The turn-on frequency can optionally be set externally via the ’SYNC’ pin. In this case the synchronization of the

PWM-on signal refers to the falling edge of the ’SYNC’-pin input signal. In case the synchronization to an external

clock signal is not needed the ’SYNC’ pin should be connected to GND.

Leaving pin SYNC open or short-circuiting it to GND leads to normal operation with the internal switching

frequency.

7.2

Electrical Characteristics Module Oscillator

Electrical Characteristics: Buck Regulator

V

Pos.

Parameter

Symbol

Limit Values

Unit

Conditions

Min.

Typ.

Max.

7.2.1

Oscillator frequency

f

osc

330

370

420

kHz

V

7.2.2

Synchronization capture range

f

sync

200

530

kHz

7.2.3

SYNC signal high level valid

V

SYNC,hi

2.9

V

1)

1) Synchronization of PWM-on signal to falling edge.

7.2.4

SYNC signal low level valid

V

SYNC,lo

0.8

V

1)

7.2.5

SYNC input internal pull-down

R

SYNC

0.60

1.0

1.4

M

Ω

V