IC category

LTC4380 Overvoltage Protection

Thomas Scherer @ elektormagazine.com writes:

When it comes to protecting sensitive circuitry from potentially damaging over-voltage spikes and supply surges we usually resort to networks of coils, capacitors, resistors and suppression diodes to iron out the transients. The LTC4380 low quiescent current surge stopper IC from Linear Technology goes about it in a different way; it looks out for over-voltage nasties and switches a fast N-channel external series-connected MOSFET to limit the surge. The chip is just 3 mm square and draws very little quiescent current.

LTC4380 Overvoltage Protection – [Link]

Inside the 74181 ALU chip: die photos and reverse engineering

A detailed die photos and reverse engineering of the 74181 ALU chip by Ken Shirriff:

What’s inside a TTL chip? To find out, I opened up a 74181 ALU chip, took high-resolution die photos, and reverse-engineered the chip.1 Inside I found several types of gates, implemented with interesting circuitry and unusual transistors. The 74181 was a popular chip in the 1970s used to perform calculations in the arithmetic-logic unit (ALU) of minicomputers. It is a moderately complex chip containing about 67 gates and 170 transistors3, implemented using fast and popular TTL (transistor-transistor logic) circuitry.

Inside the 74181 ALU chip: die photos and reverse engineering – [Link]

Software Defined Radio IC Decap

Software Defined Radio teardown: R820/RTL2832U Decap

Recently there has been much interest in two integrated circuit which were originally designed to receive FM radio and DVB-T TV (as used in Europe).
Some enterprising people quickly realised that since they were based on software-defined techniques they could be quickly re purposed for all sorts of clever things.

Software Defined Radio IC Decap – [Link]

New PWM controller IC By Microchip Charges Batteries of Any Chemistry

Battery technologies of all chemistry are experiencing revolutionary changes nowadays. Nanotechnology is leading this revolution by yielding new battery technologies including but not limited to Tiny Supercapacitors and Li-ion batteries that never explode at any condition. But, it’s bothersome to make different chargers for different types of batteries. So, Microchip solved this problem by introducing a new hybrid PWM controller, MCP19124/5, that charges batteries of any chemistry.

MCP19124 PWM Controller - 24 Pin QFN Package
MCP19124 PWM Controller – 24 Pin QFN Package

The power of this charging device lies in the combination of an 8-bit PIC microcontroller and an analog PWM controller in one package. This mixed signal low-side PWM controller features individual analog PWM control loops for both current regulation and voltage regulation. It can be configured with separate feedback networks and reference voltages. Any voltage, current, temperature, or duration can be used to trigger a transition to a different charging profile.

Various types of batteries require different charging profile. So, the only way to charge all kinds of batteries with a single device is to simulate all the charging profiles. A user can set his/her desired profile with the help of two independent current and voltage control loops, along with variable reference voltage. Now let’s get to know more details about this versatile PWM controller IC.

MCP19124/5 : 

The MCP19124/5 is a mid-voltage (4.5-42V) analog-based PWM controller with an integrated 8-bit PIC Microcontroller. There are two devices, the MCP19124 and MCP19125, where the last one has four I/O pins more than the first one. MPC19124 and MPC19125 are packaged in 24-lead QFN package and 28-lead QFN package respectively. It has following features:

  • Smooth, dynamic transitions from constant-current to constant-voltage operation
  • Dynamically adjustable output current and output voltage over a wide operating range
  • Wide operating voltage range: 4.5-42V
  • Analog peak-current mode Pulse-Width Modulation (PWM) control
  • Available fixed frequency (31 kHz to 2 MHz)
  • I2C communication interface
  • 9 GPIO for MCP 19124 and 12 GPIO for MCP19125
  • Integrated high voltage linear regulator, with external output
  • Integrated temperatures sense diode
  • Integrated 10 bit A/D converter
  • Minimal external components needed
  • Custom algorithm support
  • Topologies supported include Boost, SEPIC, Flyback, and Cuk

In fact, the above list is just a brief overview. The controller is so complicated that user must read all 236 pages of the datasheet to gain sufficient knowledge.

Now, the question is, how can we use this IC to design an efficient battery charger?

To find the answer, one must read the datasheet thoroughly. At the same time, in-depth knowledge about the target battery is also required. However, Microchip provided a few schematics (as references) in the datasheet based on different applications. The circuit on battery charger is given below:

Battery Charger Circuit Using MCP19124 ICBattery Charger Circuit Using MCP19124 IC
Battery Charger Circuit Using MCP19124 IC

This ultimate powerful dual-loop PWM controller is going to be a game changer and part of the battery technology revolution. It possesses lots of possibilities. To learn more about this fantastic hybrid controller, study the datasheet carefully.

Buck regulators accept up to 40-V input

by Susan Nordyk @ edn.com:

A wide input range of 4.5 V to 40 V enables the TS3004x series of DC/DC synchronous buck regulators from Semtech to work in a wide range of applications, including industrial, telecommunication, and consumer. The current-mode TS30041 and TS30042 furnish 1 mA and 2 mA of continuous output current, respectively, and include integrated power switches and robust fault protection in a small 3×3-mm, 16-lead QFN package.

Buck regulators accept up to 40-V input – [Link]

LT8390 – 60V Synchronous 4-Switch Buck-Boost Controller with Spread Spectrum

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The LT8390, is a synchronous buck-boost DC/DC controller that can regulate output voltage, and input or output current from input voltages above, below and equal to the output voltage. Its 4V to 60V input voltage range and 0V to 60V output voltage range are ideal for voltage regulator, battery and supercap charger applications in automotive, industrial, telecom and even battery-powered systems. The LT8390’s 4-switch buck-boost controller, combined with 4 external N-channel MOSFETs, can deliver from 10W to over 400W of power with efficiencies up to 98%. Its buck-boost capability is ideal for applications such as automotive, where the input voltage can vary dramatically during stop/start, cold crank and load dump conditions. Transitions between buck, buck-boost and boost operating modes are seamless, offering a well regulated output even with wide variations of supply voltage. The LT8390 is offered in either a 28-lead 4mm x 5mm QFN or thermally enhanced TSSOP to provide a very compact solution footprint. [source]

LT8390 – 60V Synchronous 4-Switch Buck-Boost Controller with Spread Spectrum – [Link]

Semtech TS30041 – Buck regulators accept up to 40-V input

ts3004x-bd

A wide input range of 4.5 V to 40 V enables the TS3004x series of DC/DC synchronous buck regulators from Semtech to work in a wide range of applications, including industrial, telecommunication, and consumer. The current-mode TS30041 and TS30042 furnish 1 mA and 2 mA of continuous output current, respectively, and include integrated power switches and robust fault protection in a small 3×3-mm, 16-lead QFN package. by @ edn.com

Semtech TS3004x – Buck regulators accept up to 40-V input – [Link]

MAX11311 By MAXIM Integrated

MAX11311 – The Powerful Configurable Mixed Signal I/O

The MAX11311 is industry’s first configurable high-voltage mixed-signal I/O that allows user-defined ADC, DAC, or GPIO functionality.

Programming MAX11311 is very easy. A nice GUI tool helps to generate the right register values. If you want to make a universal signal processing board with a good number of I/O, it often gets very difficult to select a correct microcontroller. Finally, when you select one, it either has less I/O than you need or has fair enough number of I/O but burns your pocket. But if you know about MAX11311, then you’ve got a perfect solution.

Description:

The MAX11311 integrates a PIXI™, a 12-bit analog-to-digital converter (ADC), and a 12-bit digital-to-analog converter (DAC) in a single integrated circuit. This device offers 12 high voltage, bipolar ports. Each of the ports is configurable as an ADC analog input, a DAC analog output, a general-purpose input output (GPIO), or an analog switch terminal. One internal and two external temperature sensors track junction and environmental temperature. This feature prevents thermal runaway. Adjacent pairs of ports are configurable as a logic-level translator for open-drain devices or an analog switch.

MAX11311 MIcrocontroller Block Diagram
MAX11311 Mixed Signal I/O Block Diagram

Features:

  • Up to 12 12-Bit ADC Inputs
    • Single-Ended, Differential, or Pseudo-Differential Range Options: 0 to 2.5V, ±5V, 0 to +10V, -10V to 0V
    • Programmable sample averaging per ADC port
    • Unique voltage reference for each ADC PIXI port
  • Up to 12 12-Bit DAC Outputs
    • Range options: ±5V, 0 to +10V, -10V to 0V
    • 25mA current drive capability with over-current protection
  • Up to 12 General-Purpose Digital I/Os (GPIO)
    • 0 to +5V GPI input range
    • 0 to +2.5V GPI programmable threshold range
    • 0 to +10V GPO programmable output range
    • Logic-Level Shifting Between any two pins
  • 60Ω analog switch between adjacent PIXI Ports
  • Internal/External temperature sensors with ±1°C Accuracy

Applications:

You can use this chip as an expansion module to MCUs in various applications. Let’s see the list:

  • Base station RF power device bias controllers
  • Control for optical components
  • Industrial control and automation
  • Power supply monitoring
  • System supervision and control
  • Universal signal processing

Conclusion:

The MAX11311 adapts perfectly to specific application requirements and allows for easy reconfiguration as the system needs further change. It also reduces BOM (Bill of Materials) cost with fewer external components in a small footprint.

To know more about this awesome chip, refer to the datasheet.

LTC3786 – Efficient boost controller takes the heat

linear-ltc3786

Linear Technology has launched a higher-temperature 150°C version of its LTC3786 step-up DC/DC controller that boasts 98% efficiency. This H-grade device replaces the boost diode with an N-channel MOSFET for higher efficiency and reduced power loss. by Susan Nordyk @ edn.com:

The controller produces a 24-V, 5-A output from a 12-V input with up to 98% efficiency, useful for automotive, industrial, and medical applications. It operates from an input voltage ranging from 4.5 V to 38 V during startup, maintains operations down to 2.5 V after startup, and regulates an output voltage as high as 60 V. Its low quiescent current of 55 µA helps extend the run time of battery-powered applications in standby mode.

LTC3786 – Efficient boost controller takes the heat – [Link]

LT8630 – 100V, 600 mA synchronous buck DC/DC betters 93% efficiency

161121edne-linear8630
LT8630 is a 600 mA, 100V input capable synchronous step-down switching regulator using synchronous rectification to deliver efficiency as high as 93% while Burst Mode operation keeps quiescent current under 7 µA in no-load standby conditions. by By Graham Prophet @ edn-europe.com:

The device’s 3V to 100V input voltage range suits it for 48V automotive systems, dual battery transportation, industrial and 36V to 72V telecom applications. Its internal high efficiency switches can deliver up to 600 mA of continuous output current to voltages as low as 0.8V.

LT8630 – 100V, 600 mA synchronous buck DC/DC betters 93% efficiency – [Link]