| 摘要 |
<p>PURPOSE:To attain the design with optional duty cycle by feeding back an output of a comparator or an amplifier to an inverting input of the comparator via a complementary circuit comprising an npn transistor(TR) and a pnp TR so as to obtain a stable temperature characteristic. CONSTITUTION:The circuit is so constituted that an output of a comparator Co or an amplifier is received and fed back to noninverting and inverting inputs of the comparator Co respectively via 2 pairs of output circuits of symetrical complementary form comprising npn TRs Q1, Q2 and pnp TRs Q3, Q4. Thus, the base-emitter voltage of the npn TRs Q1, Q2 and pnp TRs Q3, Q4 is identical. Thus, the temperature characteristic is compensated to stabilize the temperature fluctuation and the duty cycle is optionally designed by independent charge resistors R2a, R2b.</p> |
