Programming sequence

PM0064

6/13

Doc ID 16274 Rev 3

Figure 2.

Programming mode entry pulses on CS: all 4 pulses

Figure 3.

Programming mode clock on CX: double clock + time delay between

double clocks

3.2

Option read

1.

Programming mode entry (State_1): Follow steps to enter programming mode as in

Table 2.

2.

Option read (State_20) reads the options. See Table 3: Option read (State_20).

Option bit interpretation: 0 = option not programmed; 1 = option programmed.

Note:

Whenever the state of CS is changed, allow enough time for the transition to occur

depending on the CS capacitor connected to the circuit.

1

1

CS

Programming mode entry point

f = 650Hz (± 3%), t = 1 / ( 2 x f ) _ 770µs

8 µs

8 µs

16 µs

Table 3.

Option read (State_20)

Step

Action

Explanation

1.

CS = LOW

CS should be LOW to move through states 3, 7, 11, 15 into State_19.

2.

CX - 5 double clock

Clock IC until it is in State_19.

3.

CS = HIGH

CS = 1 required for transition from State_19 to State_20.

4.

CX - 1 double clock

Clock IC into State_20.

5.

CX - 1 double clock

The IC places option_0 value on OUT pin.

6.

Read option on OUT Option value is now available on OUT pin.