DS1075

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Figure 9

POWER-ON RESET

When power is initially applied to the device supply pin, a power-on reset sequence is executed, similar

to that which occurs when the device is restored from a power-down condition. This sequence comprises

two stages, first a conventional POR to initialize all on-chip circuitry, followed by a stabilization period

to allow the oscillator to reach a stable frequency before enabling the outputs:

1. Initialize internal circuitry.

2. Enable internal oscillator and/or OSCIN buffer.

3. Set M and N to maximum values.

4. Wait approximately 256 cycles of MCLK for the oscillator to stabilize.

5. Load M and N programmed values from EEPROM.

6. Enable OUT0 (assuming EN0=0).

7. Enable OUT.

Figure 10

PROGRAMMING

Normally when power is applied to the supply voltage pin the device will enter its normal operating mode

following the power-on reset sequence. However the device can be made to enter a programming mode if

a pull-up resistor is connected between IN/OUT and the supply voltage pin, prior to power-up. The

Semiconductor products.