MDT75C277

OTP Encoder

6 of 6

2006/10/11 Ver. 1.5

This specification is subject to be changed without notice. Please visit our web site for the most updated

10. Application circuit ( Reference )

1

2

3

45

6

7

8

VDD

VSS

TXD

K3

K2

K1

K0

OSCR

Vdd

Vss

Transmitter

Circuit

SW0

SW1

SW2

SW3

+

4.7u

0.1u

1MΩ

R1

(a). If encoder circuit has one switch only to control ON/OFF power & key data together,

then circuit must add R1 resister 1MΩ .

(b). To increase the stability of RC oscillator can add 100 pF capacitor at Rosc in parallel .

(c). To increase the stability of K3 ~ K0 key data can increase pull low resister 100K connect

key and Vss ,

K3 ~ K0 internal pull low resister is 450K (Vdd=9V),

information.

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