Micrel Inc., is a leading manufacturer of IC solutions for the worldwide high-performance analog and high-speed mixed signal, LAN and timing and communications solutions markets. The Company's products include high performance analog, power, advanced mixed-signal and radio frequency semiconductors; high speed communication, clock management, and LAN solutions including Ethernet switch and physical layer transceiver integrated circuits. These products address a wide range of rapidly growing end markets including cellular handsets, portable and enterprise computing, enterprise and home networking, wide area and metropolitan area networks and industrial equipment.
Micrel MIC5512/14/24 low-dropout (LDO) regulator features a low minimum operating voltage and low heat dissipation making it ideal for battery-operated applications including DSCs, GPS, PMPs, and PDAs. MIC5512/14 is an advanced general-purpose LDO ideal for powering portable devices. MIC5512/14 includes an auto-discharge feature on the output that is activated when the enable pin is low. MIC5514 features an internal pull down resistor on the enable pin that will disable the output when the enable pin is left floating. MIC5512/14 can also be put into a zero-off-mode current state, drawing virtually no current when disabled. The Micrel MIC5524 LOD regulator is designed to optimize performance in a small package. It is capable of sourcing 500mA of output current while only drawing 38µA of operating current. The MIC5524 includes an auto-discharge feature on the output that is activated when the enable pin is low and it has an internal pull down resistor on the enable pin that will disable the output when the enable pin is left floating, making it ideal for applications where the control signal is floating during processor boot up. The MIC5524 offers 2% accuracy, extremely low dropout voltage (260mV @ 500mA), and can regulate output voltages down to 1.0V. Equipped with a TTL logic compatible enable pin, the MIC5524 can be put into a zero-off-mode current state, drawing no current when disabled.
Micrel MIC2790/1/3 Power Management IC is ideal for monitoring core voltages that require rapid response in the event of a fault condition. The voltage supervisor IC features a manual reset input, enable input (MIC2793 only), capacitor-programmable reset timeout delay, and both an active-low and active-high reset output. The MIC2790/1/3 monitors system voltages that are in the range of 0.4V to 5.5V with a typical sense accuracy of 0.5% at +25°C and ±1.0% across -40°C to +125°C. The IC asserts a reset output when the sense voltage drops below the threshold or when the manual reset is pulled to a logic low. The active-low reset stays low for the duration of the reset timeout delay once the sense voltage returns to normal and the manual reset transitions to a logic high state. The reset timeout delay period is programmable from 1ms to 10s with an external capacitor. The Micrel MIC2790/1/3 operates from a low supply voltage of 1.5V to 5.5V, and is rated to operate over the temperature range of -40°C to +125°C.
Micrel's MIC3287 PWM White LED Drivers are a 1.2MHz pulse-width modulated (PWM) step-up switching regulator that is optimized for constant current white LED driving applications. With a maximum output voltage of 24V and a switch current of over 350mA, the MIC3287 drives a string of up to four white LEDs in series, ensuring uniform brightness and eliminating several ballast resistors. The MIC3287 implements a constant frequency 1.2MHz PWM current-mode control scheme. The high frequency PWM operation saves board space by reducing external component sizes. The added benefit of the constant frequency PWM control scheme as opposed to variable frequency control schemes is much lower noise and input ripple injected back to the battery source. To optimize efficiency, the feedback voltage is set to only 250mV. The MIC3287 is also available with a maximum 24V over voltage protection.
Micrel's MIC2287 PWM White LED Drivers are a 1.2MHz pulse width modulated (PWM), boost-switching regulator that is optimized for constant-current, white LED driver applications. With a maximum output voltage of 34V and a switch current of over 500mA, the MIC2287 easily drives a string of up to eight white LEDs in series, ensuring uniform brightness and eliminating several ballast resistors. The MIC2287 implements a constant frequency, 1.2MHz PWM control scheme. The high frequency PWM operation saves board space by reducing external component sizes. The added benefit of the constant frequency PWM scheme as opposed to variable frequency topologies is much lower noise and input ripple injected back to the battery source. To optimize efficiency, the feedback voltage is set to only 95mV. This reduces the power dissipation in the current set resistor and allows the lowest total output voltage, hence minimal current draw from the battery.
Micrel's KSZ84xx IEEE1588v2 Ethernet Switches & Controllers show Micrel's commitment to supporting industrial networking that is further enhanced with EtherSynch™ technology, based on IEEE1588v2 Time synchronization. EtherSynch™ technology enables an advanced, low-cost, hardware based architecture that offloads both synchronization and communications processing from the host CPU. The EtherSynch™ family of 1588v2 Ethernet switches and controllers offer highly integrated, power efficient solutions for major industrial ethernet standards such as Ethernet/IP, Profinet, ModBus/TCP and Powerlink. Development timescales are shortened with the availability of both hardware and pre-qualified PTP software stack.
Micrel's MIC4604 Half Bridge MOSFET Drivers are 85V half bridge MOSFET driver that features fast 39ns propagation delay times and 20ns driver rise/fall times for a 1nF capacitive load. The low-side and high-side gate drivers are independently controlled. The MIC4604 has TTL input thresholds. It includes a high-voltage internal diode that helps charge the high-side gate drive bootstrap capacitor. A robust, high-speed, and low-power level shifter provides clean level transitions to the high-side output. The robust operation of the MIC4604 ensures that the outputs are not affected by supply glitches, HS ringing below ground, or HS slewing with high-speed voltage transitions. Undervoltage protection is provided on both the low-side and high-side drivers.
Micrel's MIC2316x Duty Cycle Buck Regulators are a high-efficiency, 4MHz, 2A synchronous buck regulator with HyperLight® Load (HLL) mode and maximum 100% duty cycle. HLL provides very-high efficiency at light loads and ultra-fast transient response which makes the MIC2316x perfectly suited for supplying processor core voltage. An additional benefit of this proprietary architecture is very low output ripple voltage throughout the entire load range with the use of small output capacitors. The MIC2316x is designed for use with a very small 0.47µH inductor and a 10µF output capacitor that enables a total solution size, less than 1mm height. The MIC2316x has a very low quiescent current of 33µA and achieves as high as 85% efficiency at 1mA. At higher loads, the MIC2316x provides a constant switching frequency around 4MHz while achieving peak efficiencies up to 93%.
Micrel's MAQ5283 Automotive Linear Regulators are high-performance linear regulators that offer a very-wide input operating voltage range, up to 120V DC, and supplies an output current of up to 150mA. The MAQ5283 is ideal for high input voltage applications such as automotive, industrial, and telecom because it offers ±3% initial accuracy, extremely high power supply rejection ratio (75dB at 10KhZ) and an ultra-low quiescent current of 8µA. The MAQ5283 is optimized for high-voltage line transients, making it ideal for harsh environment applications. The MAQ5283 is optimized for high-voltage line transients, making it ideal for harsh environment applications. The MAQ5283 is offered in both fixed output voltage (3.3V or 5.0V) and adjustable output voltage (1.23V to 5.5V) options.
Micrel MIC2405x Buck Regulator SuperSwitcher II™ offers a constant-frequency, synchronous buck regulator featuring a unique adaptive on-time control architecture. Micrel MIC2405x operates over an input supply range of 4.5V to 19V and provides a regulated output of up to 6A of output current. The output voltage is adjustable down to 0.8V with a guaranteed accuracy of ±1%, and the device operates at a switching frequency of 600kHz. Micrel’s Hyper Speed Control architecture allows for ultra-fast transient response while reducing the output capacitance and also makes (High VIN)/(Low VOUT) operation possible. This adaptive tON ripple control architecture combines the advantages of fixed-frequency operation and fast transient response in a single device. The MIC2405x offers a full suite of protection features to ensure protection of the IC during fault conditions. These include undervoltage lockout to ensure proper operation under power-sag conditions, internal soft-start to reduce inrush current, fold back current limit, “hiccup mode” short-circuit protection and thermal shutdown. An open-drain Power Good (PG) pin is provided.
Micrel's MIC826 Voltage Supervisors are a low-current, ultra-small, voltage supervisor with manual reset input, watchdog timer, and active-high and active-low push-pull outputs. The reset outputs are asserted and held when the supply voltage falls below the factory programmed threshold voltage, when the /MR pin is pulled low, or if the watchdog times out. Reset is asserted for the reset timeout delay after the supply voltage increases above the rising threshold voltage or when manual reset input is asserted high. The MIC826 consumes a quiescent current of only 3.8µA and is offered in a tiny, space-saving, 6-pin 1.6mm x 1.6mm Thin DFN package.
Micrel's KSZ9021 Gigabit Ethernet Transceivers are a completely integrated triple speed (10Base-T/100Base-TX/1000Base-T) Ethernet Physical Layer Transceiver for transmission and reception of data on standard CAT-5 unshielded twisted pair (UTP) cable. The KSZ9021GN provides the Gigabit Media Independent Interface/Media Independent Interface (GMII/MII) for connection to GMII/MII MACs in Gigabit Ethernet Processors and Switches for data transfer at 1000Mbps or 10/100Mbps speed. The KSZ9021RN provides the Reduced Gigabit Media Independent Interface (RGMII) for direct connection to RGMII MACs in Gigabit Ethernet Processors and Switches for data transfer at 10/100/1000Mbps speed. The KSZ9021 reduces board cost and simplifies board layout by using on-chip termination resistors for the four differential pairs and by integrating a LDO controller to drive a low cost MOSFET to supply the 1.2V core. The KSZ9021 provides diagnostic features to facilitate system bring-up and debugging in production testing and in product deployment. Parametric NAND tree support enables fault detection between KSZ9021 I/Os and board. Micrel LinkMD® TDR-based cable diagnostics permit identification of faulty copper cabling. Remote and local loopback functions provide verification of analog and digital data paths.
Micrel MAQ5281 and MAQ5282 High Performance Linear Regulators offer a very wide input operating voltage range of up to 120V DC and supply an output current of up to 25mA or 50mA, respectively. These Micrel devices are ideal for high input voltage applications, such as automotive, industrial, and telecom. MAQ5281/2 offer ±3% initial accuracy, extremely high power supply rejection ratio (>90dB for MAQ5281 and 80dB for MAQ5282), and an ultra-low quiescent current of 6μA. MAQ5281/2 are optimized for high-voltage line transients, making them ideal for harsh environment applications.
Micrel MIC5019 High-Side N-Channel MOSFET Driver is an ultra-small device with integrated charge pump that is designed to switch an N-Channel enhancement type MOSFET control signal in high-side or low–side applications. MIC5019 operates from a 2.7V to 9V supply and generates gate voltages of 9.2V from a 3V supply and 16V from a 9V supply. This Micrel device consumes a low 77µA of supply current and less than 1µA of supply current in shutdown mode. In high side configurations, the source voltage of the MOSFET approaches the supply voltage when switched on. The output of the MIC5019 drives the MOSFET gate voltage higher than the supply voltage to keep the MOSFET turned on.
Micrel MIC4414/15 Low-Side MOSFET Drivers are designed to switch an N-channel enhancement type MOSFET in low-side switch applications. MIC4414 is a non-inverting driver and MIC4415 is an inverting driver. Both feature short delays and high peak current to produce precise edges and rapid rise and fall times. MIC4414/15 are powered from a 4.5V to 18V supply and can sink and source peak currents up to 1.5A, switching a 1000pF capacitor in 12ns. The on-state gate drive output voltage is approximately equal to the supply voltage (no internal regulators or clamps). High supply voltages, such as 10V, are appropriate for use with standard N-channel MOSFETs. Low supply voltages, such as 5V, are appropriate for use with many logic-level N-channel MOSFETs. In a low-side configuration, the driver can control a MOSFET that switches any voltage up to the rating of the MOSFET.
Micrel MIC26x03 SuperSwitcher IIG™ Buck Regulators are constant-frequency, synchronous DC/DC buck regulators featuring adaptive on-time control architecture. MIC26603 / MIC26903 / MIC261203 buck regulators operate over a supply range of 4.5V to 28V. It has an internal linear regulator that provides a regulated 5V to power the internal control circuitry. These devices operate at a constant 600kHz switching frequency in continuous-conduction mode and can be used to provide up to 6A (MIC26603), 9A (MIC26903), or 12A (MIC261203) of output current. The output voltage is adjustable down to 0.8V. Micrel's HyperLight Load® architecture provides the same high-efficiency and ultra-fast transient response as the Hyper Speed Control™ architecture under medium to heavy loads, but also maintains high efficiency under light load conditions by transitioning to variable frequency, discontinuous mode operation. These devices offer a full suite of protection features to ensure protection of the IC during fault conditions.
Micrel MIC28510YJL 75V/4A Hyper Speed Control™ Synchronous DC/DC Buck Regulator is an adjustable frequency device featuring unique adaptive on–time control architecture. MIC28510 operates over an input supply range of 4.5V to 75V and provides a regulated output of up to 4A of output current. The output voltage is adjustable down to 0.8V with a guaranteed accuracy of ±1%. Micrel's Hyper Speed Control architecture allows for ultra–fast transient response while reducing the output capacitance and also makes (High VIN) / (Low VOUT) operation possible. This adaptive tON ripple control architecture combines the advantages of fixed–frequency operation and fast transient response in a single device. This Micrel device offers a full suite of protection features to ensure protection of the IC during fault conditions.
Micrel KSZ9031 Gigabit Ethernet Transceivers are completely integrated triple-speed (10Base-T/100Base-TX/1000Base-T) Ethernet physical layer transceivers for transmission and reception of data on standard CAT-5 unshielded twisted pair (UTP) cable. KSZ9031MNX offers the industry-standard GMII/MII (Gigabit Media Independent Interface/Media Independent Interface) for connection to GMII/MII MACs in Gigabit Ethernet processors and switches for data transfer at 1000Mbps or 10/100Mbps. KSZ9031RNX provides the Reduced Gigabit Media Independent Interface (RGMII) for direct connection to RGMII MACs in Gigabit Ethernet processors and switches for data transfer at 10/100/1000Mbps. Micrel KSZ9031 devices reduce board cost and simplifies board layout by using on-chip termination resistors for the four differential pairs and by integrating an LDO controller to drive a low-cost MOSFET to supply the 1.2V core. This device offers diagnostic features to facilitate system bring-up and debugging in production testing and in product deployment.
Micrel MIC943x0 Ripple Blocker™ ICs are designed to provide more efficient noise suppression for today's highly sensitive data and image capturing systems. MIC94300 integrates a low-R DS(ON) current-limit switch and a low-pass filter that passes DC and blocks the AC component of the input voltage. MIC94310 is a high-performance, low dropout regulator that offers better PSRR performance from DC to 5MHz than discrete solutions. Both ICs feature an active-high enable pin for power sequencing. MIC94300 and the MIC94310 devices deliver up to 200mA and both ICs offer full current and thermal fault condition protection. This Micrel IC family is ideal for some of the most demanding portable applications, including smart phones, medical imaging, tablets/notebooks/webcams, digital still and video cameras, and more.