HA17741 Datasheet, PDF (4/18 Pages) Hitachi Semiconductor – General-Purpose Operational Amplifier (Frequency Compensated)

HA17741/PS
IC Operational Amplifier Application Examples
Multivibrator
A multivibrator is a square wave generator that uses an RC circuit charge/discharge operation to generate
the waveform. Multivibrators are widely used as the square wave source in such applications as power
supplies and electronic switches.
Multivibrators are classified into three types, astable multivibrators, which have no stable states,
monostable multivibrators, which have one stable state, and bistable multivibrators, which have two stable
states.
1. Astable Multivibrator
R₃
Vin(−)
V_CC
−
Vout
Vin(+)
C₁
+
V_EE
R₁
R_L
R₂
Figure 1 Astable Multivibrator Operating Circuit
Vin(+) 0
Vin(−) 0
Vout 0
Vertical: 5 V/div
Horizontal: 2 ms/div
Circuit constants
R₁ = 8 kΩ, R₂ = 4 kΩ
R₃ = 100 kΩ, C₁ = 0.1 µF
R_L = ∞
V_CC = 15 V, V_EE = −15 V
Figure 2 HA17741 Astable Multivibrator Operating Waveform
4