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Electronics lessons

193 lessons, each a working circuit on the simulator's bench with the theory, live measurements against the expected values and things to try.

Open the lab

DC circuits (8)
Network analysis (8)
Transients (4)
AC circuits and filters (11)
Power, transformers and three-phase (19)
Op-amps and analog ICs (18)
Oscillators (10)
Fundamentals (6)
Batteries and solar (6)
Diodes and rectifiers (9)
Transistors and thyristors (18)
Digital logic (19)
Embedded (ESP32) (23)
Systems and capstones (2)
USB and power interfaces (8)
Measurement and instruments (2)
Fabrication (3)
Embedded (Arduino) (5)
Solar PV physics (14)

DC circuits

Series resistors

One loop means one current. The same current flows through every resistor, so the resistances add and the supply…

Parallel resistors

Every branch sees the full supply voltage. Each branch draws its own current, and the branch currents add up to the…

Series-parallel network

Reduce the network step by step: combine the parallel pair first, then add the series parts. Work back out to find…

Voltage divider

Two resistors in series tap off a fraction of the supply. Vout = Vs · R2 / (R1 + R2), but only while nothing heavy…

Current divider

Current entering two parallel branches splits in inverse proportion to their resistance: the smaller resistor takes…

Wheatstone bridge

Two dividers side by side. When R1/R3 = R2/Rx the midpoints sit at the same voltage and the meter between them reads…

Light sensor (LDR divider)

A photoresistor’s resistance falls as light increases, from megohms in the dark to about a kilohm in daylight. Put it…

Continuity and short-finding

With the power off, the ohms range finds opens and shorts. This board is a chain of five resistors; one of them reads…

Network analysis

Kirchhoff’s voltage law

Go around any closed loop adding rises and subtracting drops, and you always get back to zero. Here two opposing…

Kirchhoff’s current law

Charge does not pile up at a node: the current flowing into a junction equals the current flowing out.

Mesh analysis

Give each window of the circuit its own loop current, write KVL for each loop, and solve the simultaneous equations. A…

Nodal analysis

Pick a ground, name the unknown node voltages, and write KCL at each node in terms of conductances. Two nodes give two…

Thévenin equivalent

Seen from its two output terminals, any linear network acts like one voltage source V_th in series with one resistor…

Norton equivalent

The same network can also be replaced by a current source I_N in parallel with R_N. I_N is the short-circuit current…

Superposition

In a linear circuit with several sources, the response is the sum of the responses to each source acting alone, with…

Maximum power transfer

A source with internal resistance R_s delivers the most power to a load when R_L = R_s. At that point only half the…

Transients

Capacitor charging

Through a resistor, a capacitor charges along an exponential curve. After one time constant τ = RC it reaches 63 % of…

Capacitor discharging

A charged capacitor emptying through a resistor decays exponentially toward zero. It loses 63 % of its voltage every…

RL transient

An inductor resists changes in current. Switched on, the current rises exponentially with τ = L/R. Switched off, the…

Resonant tank (LC)

Charge a capacitor, then hand it to an inductor. Energy sloshes back and forth between the electric and magnetic…

AC circuits and filters

RC low-pass filter

The capacitor’s reactance falls as frequency rises, shorting high frequencies to ground. Below f_c the signal passes…

RC high-pass filter

Swap R and C and the filter turns around: the series capacitor blocks DC and low frequencies, and passes high…

RLC series circuit

X_L rises with frequency while X_C falls. Where they are equal they cancel: the impedance drops to just R, the current…

RLC parallel circuit

With L and C in parallel, their branch currents are 180° apart. At resonance they cancel in the line, so the tank…

Single-phase AC circuit

A resistor and an inductor on 220 V mains. The voltages across them do not add arithmetically because they are 90°…

Peak, peak-to-peak and RMS

An AC voltage swings between +V_pk and −V_pk. Its RMS value is the DC voltage that would heat a resistor equally: for…

Reactance of L and C

On AC, inductors and capacitors limit current through reactance. X_L = 2πfL grows with frequency, so a coil passes low…

Capacitors in series and parallel

Capacitors combine the opposite way to resistors. In parallel their plate areas add, so C = C1 + C2. In series it is…

Twin-T notch filter

Two T-shaped networks in parallel: one low-pass (R–2C–R), one high-pass (C–R/2–C). At one frequency their outputs are…

Crystal radio

Two AM stations reach the antenna together. The coil and tuning capacitor resonate at one frequency, building up that…

Transfer functions and poles

A series R–L–C driving its capacitor is a second-order low-pass: H(s) = 1 ÷ (LCs² + RCs + 1). Its two poles sit where…

Power, transformers and three-phase

Basic transformer

Two windings on one iron core. The voltage scales with the turns ratio and the current scales inversely, so the power…

Three-phase star (Y)

Three loads share a common star point tied to neutral. Each sees the phase voltage, the line voltage between phases is…

Three-phase delta (Δ)

In a delta each load sits directly between two lines, so it sees the full line voltage. Each line current is the…

12 V → 5 V regulators

Three ways to make 5 V from 12 V, each driving the same 10 Ω load. A linear 7805 burns the difference as heat, so its…

LM317 adjustable regulator

The LM317 keeps exactly 1.25 V between OUT and ADJ. R1 across that gap passes a fixed current, which also flows…

Heat inside a sealed box

Every watt dissipated inside a sealed enclosure has to leave through its walls, so the air inside warms up and every…

Linear supply: transformer, bridge, capacitor, regulator

The four blocks of every mains supply before switch-mode: a transformer steps 220 V down and isolates it, a bridge…

Series-pass regulator (transistor + Zener)

A Zener diode makes a steady reference, but it cannot supply much current. An emitter follower copies that reference…

Split supply: ± rails for op-amps

Two secondary windings in series with their junction as ground (a centre tap) feed one bridge: its + output is…

Buck converter from parts

A MOSFET chops 12 V on and off fifty thousand times a second; the inductor and capacitor average the chopped wave. The…

Boost converter from parts

Close the switch and the inductor stores energy from 5 V; open it and the inductor’s collapsing field adds its voltage…

SEPIC: output above and below the input

A Li-ion cell runs from 4.2 V full to 3.0 V empty, but the circuit wants 3.3 V the whole time. A SEPIC converter can…

LDO vs buck: choosing a 3.3 V rail

Two ways to make 3.3 V for a 100 mA load from 12 V. The AMS1117 linear regulator burns the difference as heat: its…

Charge-pump inverter: a negative rail

No inductor at all: a 555 square wave charges C1 through D1 while its output is high, then, when the output drops…

Reverse-polarity protection with a P-MOSFET

Connect a battery backwards and the electronics die. A diode in series protects but wastes about 0.9 V. A P-MOSFET…

Inrush limiting with an NTC

An empty 4700 µF capacitor looks like a short circuit at switch-on: the first current spike can blow fuses and weld…

Opto-isolated mains switching (zero-cross SSR)

A 5 V signal switches a 220 V lamp with no electrical connection between them. The MOC3063’s LED fires a…

Fault-finding a linear supply

Symptom: the 5 V supply hums and its output dips under load. Work from the output back to the mains: check the output…

Fault-finding a switch-mode output

Symptom: the 5 V buck converter is putting out nearly 11 V. A regulator that goes high has lost its feedback. Measure…

Op-amps and analog ICs

Inverting amplifier

Negative feedback holds the op-amp’s two inputs at the same voltage. With IN+ on ground, IN− becomes a virtual ground…

Non-inverting amplifier

Feed the signal into IN+ and feed back a fraction of the output to IN−. The op-amp drives the output until that…

Voltage follower (buffer)

A divider makes a voltage, but loading it pulls that voltage down. An op-amp wired as a follower (OUT tied to IN−)…

Summing amplifier

Several inputs, each through its own resistor, meet at the virtual ground. Their currents add in R_f, so the output is…

Difference amplifier

Feed one signal to each input through matched resistors and the op-amp amplifies only their difference: V_out = (R_f /…

Integrator

Put a capacitor in the feedback path. The input current V_in/R charges it at a steady rate, so the output ramps: V_out…

Schmitt trigger

Positive feedback from the output to IN+ makes two thresholds: the output flips low when the input rises past the…

Sallen–Key low-pass filter

Two RC stages and an op-amp follower make a second-order filter: flat in the passband, then falling 40 dB per decade…

555 monostable (one-shot timer)

A short low pulse on TRIG sets the output high and lets C charge through R. When it reaches ⅔ V_CC the 555 resets and…

Common-emitter amplifier

The classic one-transistor amplifier. R1–R2 bias the base, R_E sets the emitter current and stabilises it, and a small…

Comparator with a light sensor

A comparator is an op-amp built for decisions: its output switches fully one way or the other depending on which input…

Instrumentation amplifier

Sensors like strain gauges give a few millivolts of difference riding on a few volts of common-mode voltage. An…

Baxandall tone control

Bass and treble pots sit inside the feedback network of an inverting amplifier. At low frequencies the bass capacitors…

LM386 speaker amplifier

The LM386 is a whole power amplifier in eight pins: input on pin 3, speaker on pin 5 through a big capacitor, and a…

Precision rectifier (superdiode)

A diode alone cannot rectify a 0.3 V signal: it needs 0.6 V just to conduct. Put it inside an op-amp’s feedback loop…

High-side current sensing

Measure the current into a 12 V load without breaking its ground: a 0.1 Ω shunt in the supply lead, and a difference…

Class-D amplifier from parts

Compare the audio with a fast triangle wave and you get pulses whose width follows the audio (PWM). Two MOSFETs switch…

Negative feedback and stability

An op-amp has a huge, unreliable open-loop gain A. Feed back a fraction β of the output and the closed-loop gain…

Oscillators

Op-amp relaxation oscillator

A Schmitt trigger whose own output charges a capacitor on IN− through R. When the capacitor reaches a threshold the…

555 astable (LED flasher)

C charges through R1 + R2 up to ⅔ V_CC, then the 555 shorts DIS to ground and C discharges through R2 alone down to ⅓…

Astable multivibrator (two transistors)

Two transistors take turns: when one switches on, its collector drops and the capacitor kicks the other one off until…

RC phase-shift oscillator

Three RC sections each delay the signal; at one frequency they add up to 180°. An inverting amplifier adds the other…

Wien-bridge oscillator with lamp stabiliser

A series RC and a parallel RC pass exactly one third of the signal, in phase, at f = 1/(2πRC). A non-inverting…

Colpitts and Hartley LC oscillators

An LC tank rings at its resonant frequency. A transistor tops up the energy lost each cycle: in the Colpitts the…

Crystal oscillator (Pierce)

Replace the coil of an LC oscillator with a quartz crystal: it behaves like an extremely sharp tuned circuit, so the…

UJT relaxation oscillator

A capacitor charges through a resistor until the emitter of the unijunction transistor reaches its peak-point voltage…

Neon-lamp relaxation oscillator

The capacitor charges through a large resistor. At about 90 V the neon gas ionises, the lamp flashes and drains the…

Oscillator criteria (Barkhausen)

A loop oscillates at the frequency where its total phase shift is 360° and keeps oscillating only if its loop gain…

Fundamentals

Ohm’s law

Voltage pushes, resistance resists, and current is the result: I = V / R. Double the voltage across a resistor and the…

Power and power ratings

Power is how fast energy is used: P = V · I, which also equals I² · R and V² / R. A resistor turns all of it into…

Using a multimeter

A voltmeter goes across a part (in parallel) and an ammeter goes in the loop (in series). Neither is perfect: the…

Fuses and fault current

A fuse is a deliberately weak link. At normal current it just warms slightly. During a fault the current jumps, the…

Reading colour codes and markings

Every part carries its value: colour bands on resistors, a three-digit code on ceramic capacitors (two digits and a…

Capacitor ESR check

An electrolytic capacitor fails slowly: its electrolyte dries, its capacitance falls and its internal series…

Batteries and solar

Battery internal resistance

A real battery is an ideal voltage E in series with a small internal resistance r. With no load you read E. Under…

Cells in series and parallel (LiFePO4)

Cells in series add their voltages (and their internal resistances). Cells in parallel keep the same voltage but share…

Li-ion CC/CV charger from an LM317

Li-ion cells must be charged at a limited current (CC) until they reach 4.2 V, then held at that voltage (CV) while…

Cell protection: DW01 + 8205A

Every Li-ion pack has a tiny board that disconnects the cell when it is in danger: over-charged, over-discharged…

MPPT: perturb and observe

A solar panel gives its most power at one point on its I–V curve. The ESP32 measures the panel’s voltage and current…

Ideal-diode OR-ing: USB plus battery

Two supplies feed one load and must never feed each other. Schottky diodes would waste 0.3 V. Here each supply goes…

Diodes and rectifiers

Diode forward and reverse bias

A diode is a one-way valve. Forward biased (anode positive) it conducts once about 0.6–0.7 V is across it, and that…

LED and its series resistor

An LED is a diode that emits light. Its voltage is nearly fixed (about 2 V for red, 3 V for blue or white), so it must…

Half-wave rectifier

One diode lets only the positive half-cycles through, turning AC into pulsing DC. A reservoir capacitor charges on…

Bridge rectifier and filter

Four diodes steer both half-cycles the same way through the load, so nothing is wasted and the ripple runs at twice…

Zener shunt regulator

A Zener diode is built to break down in reverse at a precise voltage. With a series resistor it holds the output…

Voltage doubler and Cockcroft–Walton multiplier

C1 and D1 clamp the AC so it swings from 0 to twice its peak; D2 and C2 then catch that peak. Stack more of these…

Diode clipper and clamper

Clipper: two diodes back to back across the output cut off anything beyond ±0.65 V. Clamper: a capacitor and one diode…

Peak and envelope detector

An AM signal is a fast carrier whose amplitude follows the audio. A diode passes the positive peaks and an RC holds…

Testing diodes and transistors with a meter

The meter’s diode range pushes about 1 mA through the part and shows the voltage across it. A good silicon junction…

Transistors and thyristors

BJT current gain (β)

In a bipolar transistor a small base current controls a collector current β times larger: I_C = β · I_B. Here a…

Transistor as a switch

Give the base far more current than I_C / β needs and the transistor saturates: fully on, with only about 0.1 V across…

Emitter follower (buffer)

Take the output from the emitter and it follows the base, about 0.65 V lower: gain ≈ 1. The base draws only I_E / (β +…

MOSFET low-side switch

A MOSFET is controlled by gate voltage, not current. Above its threshold (about 1.8 V for the logic-level IRLZ44N) the…

Inductive load and the flyback diode

A relay coil is an inductor, and an inductor’s current cannot stop instantly. When the MOSFET switches off, the coil…

Darlington pair

Feed one transistor’s emitter current into a second transistor’s base and the gains multiply: β_total ≈ β1·β2, tens of…

H-bridge motor driver

Four transistors around a motor form an “H”. Turning on one diagonal pair drives current through the motor one way…

Push-pull output stage

An NPN emitter follower can only push current out and a PNP one can only pull it in. Put one of each back to back and…

Class A, B and AB output stages

Two emitter followers, an NPN for the positive half and a PNP for the negative half, push and pull the speaker. With…

Long-tailed pair (differential amplifier)

Two matched transistors share one tail current. A difference between the bases steers the current from one side to the…

Current mirror

Q1 is wired as a diode: its collector current sets a V_BE. Q2 shares that V_BE, so, being identical and at the same…

Cascode amplifier

A common-emitter stage has a hidden capacitor from collector to base (C_μ, drawn here as a real 100 pF). Its gain…

SCR crowbar over-voltage protection

If the 5 V rail ever climbs past about 5.6 V, the Zener conducts, the SCR fires and short-circuits the rail like a…

TRIAC light dimmer with DIAC

Each half-cycle, the capacitor charges through the pot. When it reaches the DIAC’s 32 V the DIAC fires a pulse into…

Thermal flasher and relay latch (start/stop)

Left: a car indicator. Lamp current heats a bimetal strip in the flasher; it bends, opens the circuit, cools and…

Light-activated switch with relay

An LDR and a pot form a divider whose middle rises as it gets dark. A Darlington pair turns that into enough current…

LED constant-current driver

LEDs want a set current, not a set voltage. Two transistors make a current sink: Q1 carries the LED current through…

BJT small-signal model (hybrid-π)

For small signals a biased transistor is a resistor r_π between base and emitter and a current source g_m·v_be into…

Digital logic

AND gate

The output is 1 only when every input is 1. Think of two switches in series.

OR gate

The output is 1 when any input is 1. Two switches in parallel.

NOT gate

An inverter: the output is the opposite of the input.

NAND gate

AND followed by NOT: the output is 0 only when both inputs are 1. NAND is a universal gate: every other gate, and so…

NOR gate

OR followed by NOT: the output is 1 only when both inputs are 0. NOR is also universal; the Apollo guidance computer…

XOR gate

Exclusive OR: 1 when the inputs differ. It is the heart of a binary adder and of parity checks.

NAND as a universal gate

Using only NAND gates you can make NOT, AND and OR, and therefore any logic circuit. Here one 74HC00 makes NOT A (a…

Half adder

Adding two bits gives a sum bit and a carry bit: 1 + 1 = 10 in binary. The sum is A XOR B, and the carry is A AND B…

Full adder

A full adder adds three bits: A, B and the carry from the column to the right. Two half adders and an OR gate do it…

2-to-1 multiplexer

A multiplexer is a digital selector switch. With S = 0 the output copies input A, with S = 1 it copies input B. Y =…

BCD decoder and 7-segment display

A 4-bit binary number goes into a 74HC4511, which works out which of the seven segments to light for that digit. The…

SR latch (memory from two gates)

Feed two NOR gates’ outputs back into each other and the circuit remembers. A pulse on S (set) makes Q = 1, a pulse on…

D flip-flop

A D flip-flop copies its D input to Q only at the instant the clock rises, and ignores D the rest of the time. Clocked…

JK flip-flop

The JK flip-flop fixes the SR latch’s forbidden state. On each falling clock edge: J sets, K resets, both 0 holds, and…

4-bit ripple counter

Four JK flip-flops in toggle mode (J = K = 1), each clocked by the previous one’s Q. Every stage toggles at half the…

Synchronous counter (74HC161)

In a synchronous counter every flip-flop shares one clock, and gates decide which bits toggle. All the bits change at…

Shift register (74HC164)

A shift register is a row of D flip-flops sharing one clock, each feeding the next. Every clock edge moves the stored…

Logic levels and families

A logic input decides 1 or 0 by comparing its voltage with two thresholds. Mixing supply voltages can land a signal in…

Hardware debounce and power-on reset

A push button’s contacts bounce for a few milliseconds, so a counter sees five presses instead of one. An RC slows the…

Embedded (ESP32)

Interrupts and debouncing

An interrupt runs a function the instant a pin changes, even while loop() is busy, so no press is ever missed. But a…

Deep sleep and battery life

A battery device spends most of its life asleep. Awake, the ESP32 chip draws about 45 mA; in deep sleep only its…

Settings that survive a reset (NVS)

RAM is wiped every time the chip resets or loses power. To keep a setting, a calibration or a counter, a program…

Watchdog timer

Field devices hang: a sensor stops answering, a network call never returns. A watchdog is a hardware timer the program…

SPI bus: MAX7219 display

SPI is the other main serial bus. The master drives a clock (SCK) and shifts data out on MOSI while each device has…

I²C sensor: accelerometer tilt

An accelerometer at rest measures gravity. How the 1 g splits across its x, y and z axes tells you how it is tilted…

I²C sensor: temperature, humidity, pressure

Environmental sensors like the BME280 sit on the I²C bus at a fixed address and return calibrated readings. A library…

PWM actuator: hobby servo

A hobby servo is position-controlled by pulse width, not duty cycle: every 20 ms it expects a pulse between 0.5 ms…

PWM actuator: DC motor through a MOSFET

A GPIO pin gives a few milliamps; a motor wants an amp. A logic-level MOSFET switches the motor’s own supply, and PWM…

Monitoring a supply rail with the ADC

The ESP32’s ADC reads from about 0.15 V to 3.1 V at its default setting, and is only straight up to about 2.45 V. So a…

Blink: your first sketch

Every microcontroller course starts here: setup() runs once, loop() runs forever. digitalWrite() switches a pin…

Analog in, PWM out

analogRead() turns a voltage into a number from 0 to 4095, but the ESP32’s ADC is not a straight line: at its default…

Light sensor with an ESP32

An LDR and a fixed resistor make a voltage divider whose output falls as it gets darker. The sketch reads it on GPIO34…

I²C scanner

I²C devices share two wires (SDA, SCL) and each answers to its own 7-bit address. A scanner tries every address and…

16×2 I²C LCD

Show text and numbers on a character LCD over I²C. Here a 12 V adapter feeds an HW-688 for 5 V, the ESP32 reads a pot…

Wi-Fi and HTTP to the cloud

Connect to the bench access point and POST a JSON message to a server every 10 seconds. This is the last step of every…

Send an SMS with the A7670 LTE module

Cellular modules are driven by AT commands over a serial port. Press the button and the ESP32 tells the A7670 to send…

H-bridge: PWM speed, direction and braking

Four switches let current flow through the motor either way. The DRV8833 takes two logic inputs per motor: one high…

ULN2003 driver array for a stepper

An ESP32 pin can give about 20 mA at 3.3 V; a stepper phase wants 100 mA at 5 V. The ULN2003 has seven Darlington…

Bidirectional I²C level shifter (BSS138)

A 3.3 V ESP32 and a 5 V I²C device share a wire that either side may pull low. One BSS138 MOSFET per line does it…

Load-cell scale front end

Four strain gauges on a metal bar form a Wheatstone bridge whose output is a millivolt or two at full load. The HX711…

ADC front end: reference and anti-alias filter

Sampling at 1 kHz can only represent signals below 500 Hz; anything faster (here 3 kHz interference) folds down and…

Strapping pins: when the board will not boot

Five ESP32 pins are read once, as the chip leaves reset, to decide how it starts: GPIO0 (run your program, or wait for…

Systems and capstones

Sensor-to-cloud signal pipeline

A real device is a chain: a physical quantity becomes a sensor reading, travels a bus as bytes, becomes a number in…

Capstone: solar-powered GPS tracker

Everything together: a solar panel and charge controller keep a LiFePO4 battery up, a buck converter makes 5 V, the…

USB and power interfaces

USB cable voltage drop

A USB cable is two thin copper wires (VBUS and GND) plus contacts. At charging currents their resistance drops a…

USB-C attach detection (CC, Rp and Rd)

A USB-C charger keeps VBUS switched off until something that wants power is plugged in. It pulls its CC pin up through…

USB Power Delivery: asking for 20 V

After attach, a PD charger lists the voltages it can supply (Source_Capabilities) over the CC wire. The sink requests…

Charging a phone from 12 V with an HW-688

The HW-688 buck module turns 9–36 V into USB 5 V. Plug a cable into its USB-A port and the phone at the far end sees…

Detecting USB plug-in with an ESP32

A device knows a cable was plugged in by watching VBUS. Divide the 5 V down to a safe level for a 3.3 V GPIO and…

USB-C charging: the power path

Follow the energy from a USB-C charger into a TP4056 and a Li-ion cell. The TP4056 is a linear charger: the difference…

TVS, polyfuse and protection front end

A USB-powered sensor board protects itself with two parts. The TVS diode across the input does nothing at 5 V but…

Phone charging: volts, amps and watts

A phone shows the volts and amps it measures at its own USB port. A DC watt meter on the 12 V side shows what goes in…

Measurement and instruments

Using an oscilloscope

A multimeter gives you one number. An oscilloscope draws the voltage against time, so you see the shape of a signal…

Oscilloscope: comparing two signals

With two channels you can compare a signal before and after a circuit. Here a 1 kΩ / 100 nF low-pass filter is driven…

Fabrication

Perfboard: make every connection yourself

A breadboard joins each 5-hole strip for you. A perfboard joins nothing: every hole is its own island until you solder…

How a PCB works: the layer stack-up

A printed circuit board is a stack: copper etched into traces and pads, glued to fibreglass, coated with solder mask…

PCB layout: route the board and run it

Schematic → layout → simulate. The circuit on the left is the schematic: a 9 V battery, a 470 Ω resistor and a red…

Embedded (Arduino)

Arduino Uno: upload your first sketch

An Arduino is a computer on a chip with pins you can switch. It comes with Blink already loaded, so the L LED flashes…

Reading a button: floating inputs and INPUT_PULLUP

A pin set to INPUT with nothing driving it floats: it picks up hum from the room and reads random HIGHs and LOWs…

analogRead and PWM: a pot dims an LED

analogRead turns 0–5 V into a number from 0 to 1023 (10 bits). analogWrite cannot make a real voltage: it switches the…

Powering an Arduino: USB, VIN and the regulator

On USB the board runs from the computer’s 5 V (through a 500 mA fuse on the Uno). On VIN or the barrel jack, the…

Arduino Nano on a breadboard: a servo sweep

The Nano is an Uno shrunk to 45 × 18 mm, with the same ATmega328P. The Servo library makes 50 Hz pulses on any pin…