LM236 - LM336,B

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APPLICATION HINTS

The LM236, LM336 voltage references are easier

to use than zener diodes. Their low impedance

and wide current range facilitate biasing in any cir-

cuits. Besides, the breakdown voltage or the tem-

perature coefficient can be adjusted so as to opti-

mize the performance of the circuit.

Figure 1 represents a LM336 with a 10k

Ω potenti-

ometer to adjust the reverse breakdown voltage

which can be adjusted without altering the temper-

ature coefficient of the circuit. The adjustment

range is generally sufficient to adjust the initial tol-

erance of the circuit and the inaccuracy of the am-

plifier circuit.

To obtain a lower temperature coefficient two di-

odes can be connected in series as indicated in

Figure 2.

When the circuit is adjusted to 2.49V the tempera-

ture coefficient is minimized.

For a correct temperature coefficient, the diodes

should be at the same ambient temperature as the

LM336. The value of R1 is not critical (2-20k

Ω).