Circuit Diagram Profile: TAS2557 Test Circuit TAS2557 device is an advanced D audio amplifier and a fully functional chip system (SOC). The device has ultra-low noise audio DAC and a D power amplifier having a speaker voltage and current sensing feedback. Slices Low Delayed DSP Supports Texas Instruments (TI) Smartamp speaker protection algorithm, which can maximize the volume of the speaker while maintaining the speaker is in a safe state.
TAS2557 Test Circuit
TAS2557 device is an advanced D-type audio amplifier and a set of functionally complete system (SOC). The device has ultra-low noise audio DAC and a D power amplifier having a speaker voltage and current sensing feedback. Slices Low Delayed DSP Supports Texas Instruments (TI) Smartamp speaker protection algorithm, which can maximize the volume of the speaker while maintaining the speaker is in a safe state.
Multivariate oscillator circuit working principle multi-harmonic oscillator circuit is one Rectangular wave generating circuit. Such a circuit does not need to add a trigger signal, and a rectangular pulse can be generated continuously and periodically. This pulse is composed of fundamental waves and multiple harmonics, and is therefore referred to as multivalent oscillator circuits.
1. Road map
2. Two-active coupling branches of the dual steady-state trigger circuit are changed to a capacitive coupling branch. Then there is no steady state, and become an unstable circuit
3. Power on: Due to the minute difference of circuit parameters, the positive feedback makes a pipe to saturate another cutoff. A temporary state appears. Set BG1 saturation, BG2 is closed.
Positive feedback: BG1 saturation instant, VC1 is mutated from + EC to close to zero, forcing BG2’s base potential VB2 to fall near -EC, so BG2 reliable.
1. The first temporary state:
2. Flip: When VB2 is discharged with C1 When it is raised to +0.5V, the BG2 carrier is turned on, and the BG1 is closed, BG2 is saturated by positive feedback.
3. Second temporary steady state:
4. Constantly looping, forming self-excitation oscillation
5. Oscillation period: t = t1 + t2 = 0.7 (RB2 * C1 + RB1 * C2) = 1.4 RB * C
6. Oscillation frequency: f = 1 / t = 0.7 / Rb * C
7. Improvement of waveform: can be used with single organisms, using correction diode circuit
555 Multivarian oscillator circuit and principle
Working principle: The circuit is not steady state, only two temporary stabilizers, nor does it need to add trigger signals, and use the power supply Vcc to pass R1 And R2 is charged to the capacitor C, so that the UC gradually increases, when the UO is raised to a low level, the discharge terminal D is turned on, at this time, the capacitor C is discharged by resistors R2 and D, so that the UC is lowered. When the VCC / 3 is lowered, the UO hips goes to a high level, the D-terminal is closed, and the power supply Vcc is charged to the capacitor C via R1 and R2. Such cycles, oscillations, capacitors C charge and discharge between VCC / 3 and 2VCC / 3, and output a continuous rectangular pulse, and its waveform is shown in Figure (b).
555 Timer’s internal structure
Timer composed of multi-harmonic oscillators
multi-resonant oscillator composed of 555 timer Figure 3 shows that RA, RB, and C are external reference time components, and the high level trigger end (6 pin) and low level trigger end (2 foot) are connected to RB and C, will The discharge end (7 pin) is connected to the connection of RA, RB. Due to the instantaneous power of the power supply, the capacitor C is not charged, and the voltage at both ends of the capacitor is low, less than (1/3) Vcc, so the high level trigger end and the low level trigger terminal are low, and the output is high. Flat, discharge pipe V1 is closed. At this time, the power supply is charged by the capacitor C, which has risen according to the index law. When the voltage is rising (2/3) VCC, the output is low, the discharge pipe V1 is turned on, and the from (1/3) VCC rises to (2/3) VCC Since the discharge tube V1 is turned on, the capacitor C passes the resistor Rb and the discharge tube discharge, the circuit enters the second temporary state, and the length of the maintenance time is related to the discharge time of the capacitor, with C ofDischarge, decrease, when the output is high, the output is high, the discharge pipe V1 is closed, and the VCC is again charged, and the circuit is turned over to the first temporary state.
555 Multivarity Multivaride Oscillator changes the cycle and duty cycle
, as shown, the value of C1 can be changed. Adjusting RP can change the duty cycle, or replace R1 or R2 to a variable resistor for adjusting the cycle.
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