PCA2000_2001

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Product data sheet

Rev. 08 — 23 August 2010

13 of 30

NXP Semiconductors

PCA2000; PCA2001

32 kHz watch circuit with programmable adaptive motor pulse

7.8 Checking memory content

The stored data of the OTP array can be checked bit wise by measuring the supply

current. The array word is selected by the instruction state and the bit is addressed by the

shift register.

If the addressed OTP cell contains a logic 1, a 30 k

Ω resistor is connected between V

DD

Figure 8 shows the supply voltage modulation for reading word B, with the corresponding

supply current variation for word B = 110101 (sequence: first MSB and last LSB).

(1)

Fig 8.

Supply voltage modulation and corresponding supply current variation for

reading word B

(1)

mgw357

ΔI

DD

V

DD

30 k

Ω

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