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Applications information – Rainbow Electronics ADC12662 User Manual

Page 14

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Applications Information

(Continued)

TL H 11876 – 20

FIGURE 8 Buffering the Input with an LM6361 High Speed Op Amp

Correct converter operation will be obtained for input volt-
ages greater than AGND b 50 mV and less than AV

CC

a

50 mV Avoid driving the signal source more than 300 mV
higher than AV

CC

or more than 300 mV below AGND If an

analog input pin is forced beyond these voltages the cur-
rent flowing through that pin should be limited to 25 mA or
less to avoid permanent damage to the IC The sum of all

the overdrive currents into all pins must be less than 50 mA
When the input signal is expected to extend more than
300 mV beyond the power supply limits for any reason (un-
known uncontrollable input voltage range power-on tran-
sients fault conditions etc ) some form of input protection
such as that shown in

Figure 9

should be used

TL H 11876 – 21

FIGURE 9 Input Protection

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