Page 283 – Electronics-Lab.com

High Side Switch with Input Overvoltage and Overcurrent Protection

The project here is a 48V protected, high side switch designed to switch a 5A output load from input voltages from 8V to 48V. The circuit helps the user to easily ON/OFF the high current and voltage load with over-voltage lockout and over-current protection. The wide input range and low shutdown current (1μA typical) make it suitable for automotive, industrial, medical instruments, and telecom applications. This board offers a low 50ns (typical) propagation delay, fast switching times (<10ns), and 100% duty cycle operation. The project is based on LTC7000 which is a fast high voltage protected high side N-channel MOSFET driver. An internal charge pump fully enhances an external N-channel MOSFET switch, allowing it to remain on indefinitely. Its powerful gate driver can drive large gate capacitance MOSFETs with very short transition times, ideal for both high-frequency switching and static switch applications.

The circuit operates over an 8V to 48V input supply range. When an external current sense resistor and internal comparator sense that the switch current has exceeded a pre-set level, a fault flag is asserted and the switch is turned off after a period of time set by an external timing capacitor C7. After a cooldown period, it goes back on. The circuit is also configured to act when an overvoltage condition occurs. When voltage rise more than setpoint of 48V it switches off the output and remains off until input is cycled. Resistors R7, R8 are provided to set the overvoltage lockout, R10 sets the overcurrent limit, U2 5V is a regulator, Pin 3 (IMP) of CN3-CN4 provided to enable the output. This pin needs a High-level TTL-5V signal to enable the output, connect this pin to 5V to enable the output. When a fault condition occurs, disconnect the IMP pin from 5V and connect it to GND, pull up this pin to recycle the output.

Note: The project can be set for higher voltage and current, refer to the datasheet to configure the board for higher voltage up to 135V and current up to 10A.

Features

Supply 8V to 48V DC
Load Current 5Amps
Over Voltage threshold 48V
Easy On/OFF the high voltage and High Current Load
Overvoltage Lockout
Over Current Protection
PCB Dimensions 61.28 x 43.66 mm

Schematic

Parts List

NO.	QNTY.	REF.	DESC.	MANUFACTURER	SUPPLIER	SUPPLIER PART NO
1	1	CN1	2 PIN SCREW TERMINAL 5.08MM PITCH	PHOENIX	DIGIKEY	277-1247-ND
2	1	CN2	2 PIN SCREW TERMINAL 5.08MM PITCH	PHOENIX	DIGIKEY	277-1247-ND
3	1	CN3-CN4	5 PIN HEADER 2.54MM PITCH	WURTH	DIGIKEY	732-5318-ND
4	4	C1,C3,C8,C9	0.47uF/63V SMD SIZE 1206	MURATA/YAGEO	DIGIKEY	399-C1206C474KMREC7210CT-ND
5	1	C2	100uF/63V ELECTROLYTIC	NICHICON	DIGIKEY	493-6185-1-ND
6	2	C4,C7	1KPF/50V SMD SIZE 0805	MURATA/YAGEO	DIGIKEY
7	1	C5	0.1uF/50V SMD SIZE 0805	MURATA/YAGEO	DIGIKEY
8	1	C6	1uF/50V SMD SIZE 1206	MURATA/YAGEO	DIGIKEY
9	3	D1,R9,R11	DNP
10	1	Q1	FDD86369	ON SEMI	DIGIKEY	FDD86369OSCT-ND
11	1	R1	10E 5% SMD SIZE 1206	MURATA/YAGEO	DIGIKEY
12	2	R2,R3	0E SMD SIZE 0805	MURATA/YAGEO	DIGIKEY
13	1	R4	100E 5% SMD SIZE 0805	MURATA/YAGEO	DIGIKEY
14	1	R5	0.005E 1% SMD SIZE 2512	ROHM	DIGIKEY	RHM.005AUCT-ND
15	1	R6	100K 1% SMD SIZE 0805	MURATA/YAGEO	DIGIKEY
16	1	R7	750K 1% SMD SIZE 0805	MURATA/YAGEO	DIGIKEY
17	1	R8	19.1K 1% SMD SIZE 0805	MURATA/YAGEO	DIGIKEY
18	1	R10	75K 1% SMD SIZE 0805	MURATA/YAGEO	DIGIKEY
19	1	R12	82E 1% SMD SIZE 0805	MURATA/YAGEO	DIGIKEY
20	1	R13	270E 1% SMD SIZE 0805	MURATA/YAGEO	DIGIKEY
21	1	U1	LTC7000	ANALOG DEVICE	DIGIKEY	LTC7000IMSE#PBF-ND
22	1	U2	LT783	TI	DIGIKEY	296-20778-1-ND
23	1	C10	10uF/10V SMD CAPACITOR SIZE 1206	SAMSUNG	DIGIKEY	1276-1137-1-ND

Connections

Gerber View

Photos

Video

LTC7000 Datasheet

3W Stereo Differential Input CLASS-D Audio Amplifier with UP/DOWN Volume

The circuit presented here is a 3W stereo audio amplifier with memory UP/DOWN volume control. The project is based on PAM8408 IC from Diode Incorp which is a filter-less class-D amplifier with high SNR and Differential input which helps eliminate noise. Two tactile switches are provided to control the UP/DOWN volume in 32-steps and it will hold the setting when the chip is in shutdown mode. The operating supply is 2.5V to 6V DC and this supply range helps to operate it with batteries like the use of 4 x Alkaline batteries. The small PCB size, 87% efficiency, low cost, minimum external components make this project ideal for portable applications. The PAM8408 also has built-in auto-recovery SCP (Short Circuit Protection) and thermal shutdown. The circuit works with differential audio signal input. It is advisable to use shielded wire for the audio input signals. Jumper J3 is open in normal operation, and if you close it puts the amplifier into shutdown mode and the audio volume will memorize when shutdown mode is recovered. Solder jumpers J1 and J2 are optional and of no use, it is advisable to keep these jumpers open. Connector CN1 is for power supply, CN2 is for audio signal input, CN3, and CN4 are for the speaker, Jumper J3 is for Shutdown, D1 is the power LED, Switch 1 increased volume, and Switch 2 decreases volume.

Volume changes are affected by toggling either the UP or DOWN tactile switches. After a period of 1 cycle pulses with either the UP or DOWN switch press, the volume will change to the next specified step, either UP or DOWN, and followed by a short delay. This delay decreases the longer the line is held low, eventually reaching a delay of zero. The delay allows the user to pull the UP or DOWN terminal low once for one volume change, or hold down to ramp several volume changes. The delay is optimally configured for push-button volume control. If either the UP or DOWN pin remains low after the first volume transition the volume will change again, but this time after 10 cycles. The followed transition occurs at 4 cycles for each volume transition. This is intended to provide the user with volume control that pauses briefly after initial application, and then slowly increases the rate of volume change as it is continuously applied. There are 32 discrete gain settings ranging from +24dB as maximum to -80dB as a minimum. Upon device power on, the amplifier’s gain is set to a default value of 12dB, and the gain will remain when Shutdown Jumper J3 is closed.

Features

Operating Power Supply 5V (2.5V to 6V Range)
2 x 3 W Power Output 4 Ohms Speaker @ 10% THD
Fully Differential Audio Signal Input for low noise operations
Onboard Shutdown Jumper J3
D1 Power LED
Ferrite Bead on outputs for Low EMI
32-Step Memory Up/Down Volume Control from -80dB to 24dB
Low THD+N
Superior Low Noise: 60uV
Minimize Pop/Clip Noise
Auto Recovery Short Circuit Protection
Thermal Shutdown
PCB Dimensions 49.53 x 32.54 mm

Schematic

Parts List

NO.	QNTY.	REF.	DESC	MANUFACTURER	SUPPLIER	SUPPLIER PART NO
1	1	CN1	4 PIN MALE HEADER 2.54MM PITCH	WURTH	DIGIKEY	732-5317-ND
2	1	CN2	6 PIN MALE HEADER 2.54MM PITCH	WURTH	DIGIKEY	732-5319-ND
3	2	CN3,J3	2 PIN MALE HEADER 2.54MM PITCH	WURTH	DIGIKEY	732-5315-ND
4	1	CN4	4 PIN MALE HEADER 2.54MM PITCH	WURTH	DIGIKEY	732-5317-ND
5	2	C1,C3	4.7uF/16V SMD SIZE1206	MURATA/YAGEO	DIGIKEY
6	1	C2	470uF/16V or 25V	UNICORN	DIGIKEY	565-2224-1-ND
7	4	C4,C5,C6,C7	1uF/16V SMD SIZE 1206	MURATA/YAGEO	DIGIKEY
8	1	D1	LED SMD SIZE 0805	OSRAM	DIGIKEY	475-1278-1-ND
9	1	J3	JUMPER-SHUNT	SULLINS	DIGIKEY	S9001-ND
10	1	R1	1K 5% SMD SIZE 0805	MURATA/YAGEO	DIGIKEY
11	4	R2,R3,R4,R5	0E SMD SIZE 1206	MURATA/YAGEO	DIGIKEY
12	1	R6	0E SMD SIZE 0805	MURATA/YAGEO	DIGIKEY
13	1	SW1	4 PIN TACTILE SWITCH	C&K	DIGIKEY	CKN9085TR-ND
14	1	SW2	4 PIN TACTILE SWITCH	C&K	DIGIKEY	CKN9085TR-ND
15	1	U1	PAM8408	DIODE INCORP	DIGIKEY	PAM8408DRDICT-ND

Connections

Gerber View

Photos

Video

PAM8408 Datasheet

Audio-Balanced Line Driver – Unbalanced Audio to Balanced Audio Converter

Posted on 2 April, 2021 by mixos

This audio-balanced line driver project enables to drive hundreds of feet in length of cables without becoming unstable The project is based on the THAT1646 chip, which is a new generation monolithic differential line driver that offers improved performance over conventional cross-coupled designs. Based on high performance, fully differential op-amp exhibits low noise and distortion, high slew rate, and wide output swing. Output is very stable when driving difficult loads, and output is short-circuit protected. The operating power supply is +/-15V DC, XLR, and RCA connector provided for output and input. D1, D2 are the Power LEDs, C7 decoupling capacitor, Ferrite Bead L1, L2, capacitor C6, C8, C9 take cares of RFI noise, Capacitors C5, and C10 acouple the common-mode feedback loop. This changes the loop operation from serving the common-mode output current at audio frequencies to serving the common-mode output voltage to 0 at DC. This results in much lower common-mode output offset voltage. D1 +VCC Power LED, D2 -VEE Power LED, CNX-J1 single-ended unbalanced audio input, CN3 Male XLR balanced audio output, CN1 power input, CN2 or J1-CNX audio input.

Audio-Balanced Line Driver – Unbalanced Audio to Balanced Audio Converter – [Link]

+/-10V (Dual 10V) to Single-Supply Signal Converter for ADC

Posted on 2 April, 2021 by mixos

This board will make your work easy if you want to interface +/- 10V (Dual 10V) device or sensor to single-supply signal ADC. This tiny project has been made for industrial and process control applications and provides an easy interface between +/-10V (Dual 10V) sensor or device to single-supply ADC. Connect +/-10V sensor/device to pin 3 of connector CN1, and circuit outputs 0.5V to 4.5V at pin 3 of connector CN2. The operating supply of the circuit is 5V and it draws few milliamps of current. The project is also provided with optional precision Ref voltage for accurate output.

+/-10V (Dual 10V) to Single-Supply Signal Converter for ADC – [Link]

1.2V to 50V @ 3A – Adjustable Power Supply with 55Vdc Input

Posted on 2 April, 20215 April, 2021 by mixos

The project presented here is a wide input voltage range non-isolated DC-DC Converter, that provides a regulated, adjustable output voltage. The operating input supply is 55V DC and output regulated from 1.2V to 50V DC. The project built using LM2576HVT-ADJ IC. Screw terminals provided for easy input and output connections, onboard power LED at the input, bridge rectifier for AC/DC Input, an onboard potentiometer to adjust the output voltage, etc. This is a low-profile board with a thermal area on PCB that acts as a heatsink. An additional LC filter using C5 and L2 that reduces the output ripple by a factor of 10 or more is included in this circuit. The device has a current limiting feature to prevent the switching current from exceeding a safe value during an accidental overload on output.

1.2V to 50V @ 3A – Adjustable Power Supply with 55Vdc Input – [Link]

Galvanic Isolated 8 Channel High-Side Switch (0.6A per channel)

This project provides 8 fully protected and isolated high-side power switches that are able to handle current up to 625 mA. An 8-bit parallel microcontroller compatible interface allows connecting the inputs directly to a microcontroller or standalone circuit system. The input interface also supports direct control mode and is designed to operate with 3.3/5V CMOS compatible levels. The signal transfer from input to output side is realized by the integrated Coreless Transformer Technology. The board is designed for industrial applications such as process control and PLC to drive inductive, resistive, and capacitive loads like Relay, solenoid, lamps, heaters, piezo.

The input can be driven by applying 3.3V/5V CMOS compatible signals to connector CN1. It can operate in microcontroller Mode by using Chip Select and Write Signals or in Direct Control Mode by closing the Jumper J1 and J2 and setting the Data Input from D0 to D7. The Output consists of 8 Channel High Side Switches with 0.6A Current rating. The Output is protected with a channel selected over-temperature switch (to off). The 8 high-side power switches are controlled by means of the integrated parallel interface. The interface is 8-bit μC compatible. Furthermore, a direct control mode can be selected that allows the direct control of the outputs OP0…OP7 by means of the inputs D0…D7 without any additional logic signal. The μC compatible interface allows a direct connection to the ports of a microcontroller without the need for other components. Each of the 8 high-side power switches is protected against short to +DC (VBB), overload, over-temperature, and against over-voltage by an active Zener clamp.

Features

+DC(VBB) Load Power Supply 11V to 45V (CN2)
Logic Supply input Side 3.3V to 5V (CN1)
LED D1 Power LED Logic Supply (Input Side)
LED D2 LED On When (overtemperature or Vbb (+DC) below ON-Limit is detected)
Load CN3 to CN7
Interface 3.3/5V CMOS operation compatible
Parallel interface
Direct control mode
High common-mode transient immunity
Short circuit protection
Maximum current internally limited
Overload protection
Overvoltage protection (including load dump)
Undervoltage shutdown with auto-restart and hysteresis
Switching inductive loads
Common output disable pin
Thermal shutdown with restart
Thermal independence of separate channels
Common diagnostic output
ESD protection
Loss of -GNDBB (GNDbb) and loss of +DC(Vbb) protection
Reverse Output Voltage protection
Isolated return path for DIAG signal
+DC (Vbb) monitoring
PCB dimensions: 87.49 x 62.07 mm

Testing the Project

Direct mode: CLOSE the Jumper J1, and J2, open the Jumper J3, Connect the Load between OP to GDB, apply load power supply to CN2, apply logic supply to CN1, Output will be default high due to pullup Resister network on input, pull down the input pin D0 by connecting to GND or using micro-controller, the output will be OFF. LED D1 Power LED for logic supply, LED D2 turn ON When overtemperature or Vbb (+DC) below ON-Limit is detected.

Jumper J3 (DIS) DIS (Output disable) Jumper J3 Close = Disable Output, Open Enables the Output

The high-side outputs OUT0…OUT7 can be immediately switched off by means of the low active pin DIS that is an asynchronous signal. The input registers are also reset by the DIS signal. The Output remains switched off after a low-high transition of the DIS signal, till new information is written into the input register. Current Sink to GNDCC.

Micro-Controller Mode: μC Control Mode /CS – Chip select. The system microcontroller selects the ISO1H811G by means of the CS pin. Whenever the pin is in a logic low state, data can be transferred from the μC. /WR – Write. The system controller enables the writing procedure in the ISO1H811G by means of the signal WR. A logic low state signal at pin WR writes the input data into the input latches when the CS pin is in a logic low state. D0…D7. The parallel input data is transferred to the input latches with a high-to-low transition of the signal /WR (write) while the /CS is logic low. Then a low-to-high transition of /CS transfers the data of the input latches to the output buffer. The μC Control Mode can be operated by connecting a Processor Board to the corresponding Signals of Connector CN1. Refer to datasheet of the chip to operate in micr0-controller mode.

Schematic

Parts List

NO.	QNTY.	REF.	DESC	MANUFACTURER	SUPPLIER	SUPPLIER PART NO
1	1	CN1	16 PIN MALE HEADER 2.54MM PITCH	ADAM TECH	DIGIKEY	2057-PH1-16-UA-ND
2	6	CN2-CN7	2 PIN SCREW TERMINAL 5.08MM PITCH	PHOENIX	DIGIKEY	277-1247-ND
3	1	C1	470uF/50V ELECTROLYTIC	PANASONIC	DIGIKEY	P10400TB-ND
4	2	C2,C4	0.1uF/50V SMD SIZE 0805	MURATA/YAGEO
5	1	C3	1uF/50V SMD SIZE 1206 OR 1210	MURATA/YAGEO
6	1	C5	10uF/10V TANTALUM SIZE 1210 OR 1206	AVX CORPORATION	DIGIKEY	478-3451-1-ND
7	1	C6	10uF/50V SMD SIZE 1210	MURATA/YAGEO
8	2	D1,D2	LED SMD SIZE 0805	OSRAM	DIGIKEY	475-1278-1-ND
9	3	J1,J2,J3	JUMPER/SHUNT	SULLINS	DIGIKEY	S9001-ND
10	4	R1,R2,R3,R5	4.7K 5% SMD 0805	MURATA/YAGEO
11	1	R4	1K 5% SMD 0805	MURATA/YAGEO
12	1	U1	ISO1H811G	INFINION	DIGIKEY	ISO1H811GAUMA1CT-ND
13	1	RN1	4.7K RAPCK 9 PIN	BOURNS INC	DIGIKEY	4309R-101-472LF-ND

Connections

Truth Table

Gerber View

Photos

Video

ISO1H811G Datasheet

Knowles IA611 SmartMic Voice Wake Audio Processor

Posted on 1 April, 2021 by mixos

Knowles IA611 SmartMic Voice Wake Audio Processor features an “always-on” Processor providing a Voice Wake and Voice ID keyword detector, a two-second buffer, and Knowles’ proven high performance acoustic SiSonic™ MEMS microphone technology in a single, miniature, top-port package.

The Knowles IA611 SmartMic Voice Wake Audio Processor offers flexibility by supporting the most relevant audio and data interfaces. The IA611 provides integrated programmable DSP with 248kBytes of RAM available for customers and 3rd party algorithms, enabling unlimited creativity. The solution pushes the system performance to ultra-low-power with its custom core design and accelerates time to market with its highly integrated combination of hardware, software, and firmware.

Features

High-accuracy Voice Wake and Voice ID keyword recognition to wake-up any system from a trigger phrase
Minimum latency when burst out two-second audio buffer using SPI
Ultra-low-power “always on” acoustic activity
Detector (AAD) capable waking the embedded DSP
Interrupt signal to the host processor when a voice keyword trigger is detected
Integrated power tree from a single 1.8V supply
Extra flexibility with I²C/UART interfaces
248kB RAM, 160MFLOPS, 43MHz, 32-bit complex valued floating-point ALU, low-power open developer platform with SDK
High-performance acoustic SiSonic MEMS with ±1dB matched sensitivity, 65.5dB SNR and 132.5dB SPL AOP
Packaged in SPK 4.00 x 3.00 x 1.30mm

more information: https://solutions.knowles.com/hardware/application/3/IA610-Ear,IA611-Ear

New Humidity Sensors Based on MEMS Technology Offer Fast Response Time and High Accuracy/Sensitivity in a Small Footprint

Posted on 1 April, 2021 by mixos

Bourns has upgraded its line of humidity sensors with the new Model BPS240 series that meets advanced sensor needs with fast response time, high accuracy/sensitivity in a small footprint. Based on Microelectromechanical Systems (MEMS) technology, the new devices in the series offers upgraded features compared to BPS230 humidity sensors released previously by the company.

The Model BPS240 series humidity sensor is designed to meet advanced sensor needs for immediate updates on relative humidity levels in a broad range of industrial automation, energy, building, and home control, and low/medium-risk medical applications. The devices also help meet energy-efficient application requirements with their low voltage operation, reduced current consumption, and reliable embedded capacitive technology.

Faster response time of less than one second with digital (I²C) output and higher accuracy with a typical RH accuracy of 2% are the key features of the new devices released. Besides, the sensors deliver reliability in a small size (2.0 x 2.0 x 1.25 mm) footprint. The new Bourns Model BPS240 humidity sensor series is RoHS compliant and is available from the company website.

Features of BPS240 Series Humidity Sensors

Low voltage operation
Low current consumption
Fast response time
I2C communication protocol
Reliable capacitive technology
Relative humidity accuracy of ±2 %

more information: https://www.bourns.com/home

Ultra-portable Handheld Microwave Spectrum Analyzers Supporting 6 GHz – 20 GHz

Posted on 1 April, 2021 by mixos

SAF Tehnika has expanded its Spectrum Compact family of ultra-portable handheld microwave spectrum analyzers with the introduction of a model that supports 6 GHz – 20 GHz. Providing best-in-class price/performance, the new Spectrum Compact delivers high durability at an affordable price point, making it a perfect tool for field engineers and technicians responsible for link planning, installation, site acceptance, maintenance, and troubleshooting of wireless networks.

The 6-20 GHz spectrum analyzer has high sensitivity of -110 dBm at 30 kHz resolution bandwidth, long battery life of up to 4 hours, and instant-on functionality for quick start-up and operation. All this high-performance is designed in a rugged, ultra-compact form factor that measures only 135 x 83 x 34 (mm)/ 5.31 x 3.27 x 1.34 (inches) and weighs 0.57 kg/20.11 oz. It is ideal for mobile carriers, telecommunications professionals, Internet service providers (ISPs), and contractors responsible for regulatory and compliance, drone applications, and satellite operations.

Every aspect of the Spectrum Compact family has been designed to address the challenges of field applications. Similar to all Spectrum Compact models, the 6 GHz – 20 GHz handheld spectrum analyzer has a resistive touchscreen for operation with gloves, and high contrast and full display modes for easy readability in bright light environments. Durable thumbscrews for the waveguide adapter connections help the Spectrum Compact to withstand harsh environments. Spectrum traces can be saved in the integrated 8 GB of memory, for offline analysis, investigation, and reporting using the Spectrum Manager PC software.

The 6 GHz – 20 GHz instrument extends the frequency range for the Spectrum Compact family. Included in the series are the world’s only portable E-band (70-87 GHz) and V-band (56-71 GHz) handheld spectrum analyzers.

Spectrum Compact devices are well suited for mobile operators, carriers, and tower installation crews deploying 5G networks, Wireless Internet Service Providers (WISPs), local government institutions, public safety departments, and critical network infrastructure owners. Field engineers and technicians can use the ultra-portable handheld microwave spectrum analyzers to conduct site surveys, radio parameter verification, antenna alignment, interference detection, line-of-sight verification, signal strength mapping, and interference hunting.

more information: https://spectrumcompact.com

LTC2971 2-Channel ±60 V Power System Manager

Posted on 1 April, 2021 by mixos

Analog Devices’ DC2875A is a demonstration system for the LTC2971 power system manager that interfaces to various regulators.

ADI’s LTC2971, LTC2971-1, LTC2971-2, and LTC2971-3 are 2-channel high voltage power system managers used to sequence, trim (servo), margin, supervise, manage faults, provide telemetry, and log faults.

The DC2875A is a demonstration system for the LTC2971 power system manager that interfaces with various regulators. The board contains all the circuitry needed to demonstrate a power system that utilizes two 2-channel LTC2971 devices that manage four power supplies. The four power supplies include various switching regulators for demonstrating a variety of methods to sense voltage and current. The demo board provides a sophisticated 4-channel digitally programmable power supply system.

Features

Natively sense and monitor negative voltage supplies, eliminating external level shift circuitry which saves cost, simplifies design, and improves accuracy
Internal EEPROM with ECC provides essential black box fault logging, allowing for faster failure analysis and system debug
±0.25 % TUE differential ADC (sets trim, margin, and monitoring accuracy) improves the accuracy of 2 supplies, minimizing overdesign and cost, optimizing performance, and saving power

more information: https://www.analog.com/en/products/ltc2971.html