Control Signals of 8085: The 8085 Microprocessor provides RD and WR signals to initiate read or write cycle. Because these Control Signals of 8085 are used both for reading/writing memory and for reading/writing an input device, it is necessary to generate separate read and write signals for memory and I/O devices. The 8085 provides IO/M […]

## Power on Reset Circuit of 8085

Power on Reset Circuit in 8051: On reset, the PC sets to 0000H which causes the 8085 to execute the first instruction from address 0000H. For proper reset operation reset signal must be held low for at least 3 clock cycles. The power-on Reset Circuit of 8085 can be used to ensure execution of first […]

## Latching Circuit

Latching Circuit: We know that AD0 to AD7 lines are multiplexed and the lower half of address (A0 – A7) is available only during T1 of the machine cycle. This lower half of address is also necessary during T2 and T3 of machine cycle to access specific location in memory or I/O port. This means […]

## Voltage and Current Divider Rule

Voltage and Current Divider Rule: Voltage and Current Divider Rule is explained by two conditions, namely Voltage Division in Series Circuit of Resistors Current Division in Parallel Circuit of Resistors Voltage Division in Series Circuit of Resistors: Consider a series circuit of two resistors R1 and R2 connected to source of V volts is shown […]

## Routh Criterion

Routh Criterion: Routh Criterion – The locations of the poles gives us an idea about stability of the active network. Consider the denominator polynomial To get a stable system, all the roots must have negative real parts. There should not be any positive or zero real parts. This condition is not sufficient. Let us consider […]

## Stability Criterion in Network Function

Stability Criterion in Network Function: Stability Criterion – Passive networks are said to be stable only when all the poles lie in the left half of the s-plane. Active networks (containing controlled sources) are not always stable. Consider transformed active network shown in Fig. 14.13. By applying Millman Theorem, we get From the above transformed […]

## Poles and Zeros of Time Domain Response

Poles and Zeros of Time Domain Response: For the given network function, a pole zero plot can be drawn which gives useful information regarding the critical frequencies. The Poles and Zeros of Time Domain Response can also be obtained from pole zero plot of a network function. Consider an array of poles shown in Fig. […]

## Conditions For Driving Point Function

Conditions For Driving Point Function: The restrictions on pole and zero locations in the Conditions For Driving Point Function with common factors in P(s) and Q(s) cancelled are listed below. 1. The coefficients in the polynomials P(s) and Q(s) of network function N(s) = P(s)/Q(s) must be real and positive. 2. Complex poles or imaginary […]

## Poles and Zeros of Transfer Function

Poles and Zeros of Transfer Function: Poles and Zeros of Transfer Function defines that, in general, the network function N(s) may be written as where a0,a1,…a2?and b0,b1,…bm?are the coefficients of the polynomials P(s) and Q(s); they are real and positive for a passive network. If the numerator and denominator of polynomial N(s) are factorized, the […]

## Transfer Function of Two Port Network

Transfer Function of Two Port Network: For a one-port network, the driving point impedance or impedance of the network is defined as The reciprocal of the impedance function is the driving point admittance function, and is denoted by Y(s). For the Transfer Function of Two Port Network without internal sources, the driving point impedance function […]