Microchip Technology

**Consider MIC3003 for New Designs** The MIC3001 enables the implementation of sophisticated, hot-pluggable fiber optic transceivers with intelligent laser control and an internally calibrated digital diagnostic monitoring interface per SFF-8472. It essentially integrates all non-data path functions of an SFP transceiver into a tiny (4mm x 4mm) QFN package. A highly-configurable automatic power control (APC) circuit controls laser bias. Bias and modulation are temperature compensated using dual DACs, an on-chip temperature sensor, and NVRAM look-up tables. A programmable internal feedback resistor provides unprecedented dynamic range for APC. Controlled laser turn-on facilitates hot plugging. An analog-to-digital converter converts the measured temperature, voltage, bias current, transmit power, and received power from analog to digital. An EEPOT provides front-end adjustment of RX power. Each parameter is compared against user-programmed warning and alarm thresholds. Analog comparators and DACs provide high-speed monitoring of received power and critical laser operating parameters. Data can be reported as either internally calibrated or externally calibrated. An interrupt output, power-on hour meter, and data-ready bits add user friendliness beyond SFF-8472. The interrupt output and data-ready bits reduce overhead in the host system. The power-on hour meter logs operating hours using an internal real-time clock and stores the result in NVRAM. Communication with the MIC3001 is via an industry standard 2-wire serial interface. Nonvolatile memory is provided for serial ID, configuration, and separate OEM and user scratchpad spaces. Two-level password protection guards against data corruption.

**FOM Controller with Internal Calibration** The MIC3003 enables the implementation of sophisticated, hot-pluggable fiber optic transceivers with intelligent laser control and an internally calibrated digital diagnostic monitoring interface per SFF-8472. It essentially integrates all non-data path functions of an SFP transceiver into a tiny (4mm x 4mm) QFN package. A highly-configurable automatic power control (APC) circuit controls laser bias. Bias and modulation are temperature compensated using dual DACs, an on-chip temperature sensor, and NVRAM look-up tables. A programmable internal feedback resistor provides unprecedented dynamic range for APC. Controlled laser turn-on facilitates hot plugging. An analog-to-digital converter converts the measured temperature, voltage, bias current, transmit power, and received power from analog to digital. An EEPOT provides front-end adjustment of RX power. Each parameter is compared against user-programmed warning and alarm thresholds. Analog comparators and DACs provide high-speed monitoring of received power and critical laser operating parameters. Data can be reported as either internally calibrated or externally calibrated. An interrupt output, power-on hour meter, and data-ready bits add user friendliness beyond SFF-8472. The interrupt output and data-ready bits reduce overhead in the host system. The power-on hour meter logs operating hours using an internal real-time clock and stores the result in NVRAM. In addition to the features listed above which are already implemented in the previous MIC300x controllers, the MIC3003 features an extended temperature range, options to mask alarms and warnings interrupt and TXFAULT, a reset signal source, and the ability to support up to four chips with the same address on the serial interface. It also supports eight-byte SMBus block writes. Communication with the MIC3003 is via an industry standard 2-wire SMBus serial interface. Nonvolatile memory is provided for serial ID, configuration, and separate OEM and user scratchpad spaces.

The MIC2172 and MIC3172 are complete 100kHz SMPS current-mode controllers with internal 65V 1.25A power switches. The MIC2172 features external frequency synchronization or frequency adjustment, while the MIC3172 features an enable/shutdown control input. Although primarily intended for voltage step-up applications, the floating switch architecture of the MIC2172/3172 makes it practical for step-down, inverting, and Cuk configurations as well as isolated topologies. Operating from 3V to 40V, the MIC2172/3172 draws only 7mA of quiescent current making it attractive for battery operated supplies. The MIC3172 is for applications that require on/off control of the regulator. The MIC3172 is externally shutdown by applying a TTL low signal to EN (enable). When disabled, the MIC3172 draws only leakage current (typically less than 1µA). EN must be high for normal operation. For applications not requiring control, EN must be tied to VIN or TTL high. The MIC2172 is for applications requiring two or more SMPS regulators that operate from the same input supply. The MIC2172 features a SYNC input which allows locking of its internal oscillator to an external reference. This makes it possible to avoid the audible beat frequencies that result from the unequal oscillator frequencies of independent SMPS regulators. A reference signal can be supplied by one MIC2172 designated as a master. To insure locking of the slave's oscillators, the reference oscillator frequency must be higher than the slave's. The master MIC2172's oscillator frequency is increased up to 135kHz by connecting a resistor from SYNC to ground (see applications information). The MIC2172/3172 is available in an 8-pin plastic DIP or SOIC for -40°C to +85°C operation.

The MIC3202 is a hysteretic, step-down, constant-current, High-Brightness LED (HB LED) driver. It provides an ideal solution for interior/exterior lighting, architectural and ambient lighting, LED bulbs, and other general illumination applications. The MIC3202 is well suited for lighting applications requiring a wide-input voltage range. The hysteretic control gives good supply rejection and fast response during load transients and PWM dimming. The high-side current sensing and on-chip current-sense amplifier delivers LED current with ±5% accuracy. An external high-side current-sense resistor is used to set the output current. The MIC3202 offers a dedicated PWM input (DIM) which enables a wide range of pulsed dimming. High-frequency switching operation of up to 1MHz allows the use of smaller external components, minimizing space and cost. The MIC3202 offers a frequency dither feature for low-EMI applications. The MIC3202 operates over a junction temperature from -40°C to +125°C and is available in an 8-pin e-Pad SOIC package. A dither disabled version MIC3202-1 is also available in the same package as the MIC3202.

The MIC3203 is a hysteretic, step-down, constant-current, High-Brightness LED (HB LED) driver. It provides an ideal solution for interior/exterior lighting, architectural and ambient lighting, LED bulbs, and other general illumination applications. The MIC3203 is well suited for lighting applications requiring a wide-input voltage range. The hysteretic control gives good supply rejection and fast response during load transients and PWM dimming. The high-side current sensing and on-chip current-sense amplifier delivers LED current with ±5% accuracy. An external high-side current-sense resistor is used to set the output current. The MIC3203 offers a dedicated PWM input (DIM) which enables a wide range of pulsed dimming. A high-frequency switching operation up to 1.5MHz allows the use of smaller external components minimizing space and cost. The MIC3203 offers frequency dither feature for EMI control. The MIC3203 operates over a junction temperature from -40°C to +125°C and is available in an 8-pin SOIC package. A dither disabled version MIC3203-1 is also available in the same package as the MIC3203.

The MIC3205 is a hysteretic, step-down, high-brightness LED (HB LED) driver with a patent pending frequency regulation scheme that maintains a constant operating frequency over input voltage range. It provides an ideal solution for interior/exterior lighting, architectural and ambient lighting, LED bulbs, and other general illumination applications. The MIC3205 is well suited for lighting applications requiring a wide input voltage range. The hysteretic control provides good supply rejection and fast response during load transients and PWM dimming. The high-side current sensing and on-chip current-sense amplifier deliver LED current with ±5% accuracy. An external high-side current-sense resistor is used to set the output current. The MIC3205 offers a dedicated PWM input (DIM) which enables a wide range of pulsed dimming. A high-frequency switching operation up to 1.5MHz allows the use of smaller external components minimizing space and cost. The MIC3205 operates over a junction temperature from –40°C to +125°C

The MIC3223 is a constant current boost LED driver capable of driving a series string of high power LEDs. The MIC3223 can be used in general lighting, bulb replacement, garden pathway lighting, and other solid state illumination application. The MIC3223 is a peak current mode control PWM boost regulator and the 4.5V and 20V operating input voltage range allows multiple applications from a 5V or a 12V bus. The MIC3223 implements a fixed internal 1MHz switching frequency to allow for a reduction in the design footprint size. Power consumption has been minimized through the implementation of a 200mV feedback voltage that provides an accuracy of ±5%. The MIC3223 can be dimmed through the use of a PWM signal and features an enable pin for a low power shutdown state. The MIC3223 is a very robust LED driver and offers the following protection features: over voltage protection (OVP), thermal shutdown, switch current limiting and under voltage lockout (UVLO). The MIC3223 is offered in a low profile exposed pad 16-pin TSSOP package.

The MIC3230/1/2 are constant current boost switching controllers specifically designed to power one or more strings of high power LEDs. The MIC3230/1/2 have an input voltage range from 6V to 45V and are ideal for a variety of solid state lighting applications. The MIC3230/1/2 utilizes an external power device which offers a cost conscious solution for high power LED applications. The powerful drive circuitry can deliver up to 70W to the LED system. Power consumption has been minimized through the implementation of a 250mV feedback voltage reference providing an accuracy of ±3%. The MIC323x family is dimmable via a pulse width modulated (PWM) input signal and also features an enable pin for low power shutdown. Multiple MIC3230 ICs can be synchronized to a common operating frequency. The clocks of these synchronized devices can be used together in order to help reduce noise and errors in a system. An external resistor sets the adjustable switching frequency of the MIC3230/1. The switching frequency can be between 100kHz and 1MHz. Setting the switching frequency provides the mechanism by which a design can be optimized for efficiency (performance) and size of the external components (cost). The MIC323x family of LED drivers also offer the following protection features: Over voltage protection (OVP), thermal shutdown and under voltage lockout (UVLO). The MIC3231 offers a dither feature to assist in the reduction of EMI. This is particularly useful in sensitive EMI applications, and provides for a reduction or emissions by approximately 10dB. The MIC3232 is a 400kHz fixed frequency device offered in a small MSOP-10 package. The MIC3230/1 are offered in both the ePad TSSOP-16 package.