LM236-LM336

Application information

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Application information

The LM236, LM336 voltage references are easier to use than zener diodes. Their low

impedance and wide current range facilitate biasing in any circuits. Besides, the breakdown

voltage or the temperature coefficient can be adjusted so as to optimize the performance of

the circuit.

Figure 9 represents a LM336 with a 10k

Ω potentiometer to adjust the reverse breakdown

voltage which can be adjusted without altering the temperature coefficient of the circuit. The

adjustment range is generally sufficient to adjust the initial tolerance of the circuit and the

inaccuracy of the amplifier circuit.

To obtain a lower temperature coefficient two diodes can be connected in series as

indicated in Figure 10.

When the circuit is adjusted to 2.49V the temperature 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).

Figure 9.

LM336 with pot for adjustment of

breakdown voltage

Figure 10.

Temperature coefficient adjustment