Analog Devices Inc./Maxim Integrated

The MAX3942 is designed to drive high-speed optical modulators at data rates up to 10.7Gbps. It functions as a modulation circuit, with an integrated control op amp externally programmed by a DC voltage.A high-bandwidth, fully differential signal path is internally implemented to minimize jitter accumulation. When a clock signal is available, the integrated data-retiming function can be selected to reject input-signal jitter.The MAX3942 receives differential CML signals (groundreferenced) with on-chip line terminations of 50Ω. Each of the differential outputs has an on-chip 50Ω resistor for back termination. The driver is able to deliver a modulation current of 40mAP-Pto 120mAP-P, with an edge speed of 23ps (typical 20% to 80%). This modulation current reflects a modulation voltage of 1.0VP-Pto 3.0VP-Psingle ended or 2.0VP-Pto 6.0VP-Pdifferential.The MAX3942 also includes an adjustable pulse-width control circuit to precompensate for asymmetrical modulator characteristics. It is available in a compact 4mm x 4mm, 24-pin thin QFN package and operates over the -40°C to +85°C temperature range.Applications10Gbps EthernetDWDM SystemsLong/Short-Reach Optical TransmittersMach Zehnder ModulatorsPackaged Direct-Modulated LasersSONET OC-192 and SDH STM-64 Transmission Systems

The MAX3949 is a 3.3V, multirate, low-power laser diode driver designed for Ethernet, Fibre Channel, and SONET transmission systems at data rates up to 11.3Gbps. This device is optimized to drive a differential transmitter optical subassembly (TOSA) with a 25Ω flex circuit. The unique design of the output stage enables use of unmatched TOSAs.The device receives differential AC-coupled signals with on-chip termination. It can deliver laser modulation currents of up to 85mA at an edge speed of 22ps (20% to 80%) into a 5Ω external differential load. The device is designed to have a high-bandwidth differential signal path with on-chip back termination resistors integrated into its outputs. An input equalization block can be activated to compensate for SFP+ host connector losses. The integrated bias circuit provides programmable laser bias currents up to 105mA. Both the laser bias current generator and the laser modulator can be disabled from a single pin.The use of a 3-wire digital interface reduces the pin count while permitting adjustment of input equalization, polarity, output deemphasis, and modulation and bias currents without the need for external components. The device is available in a 3mm x 3mm, 16-pin TQFN package, and is specified for the -40°C to +95°C extended temperature range.Applications10GBASE-LR SFP+ Optical Transceivers10GBASE-LRM SFP+ Optical TransceiversOC192-SR SFP+ SDH/SONET Transceivers

The MAX395 8-channel, serially controlled, single-pole/single-throw (SPST) analog switch offers eight separately controlled switches. The switches conduct equally well in either direction. On-resistance (100Ω max) is matched between switches to 5Ω max and is flat (10Ω max) over the specified signal range.These CMOS devices can operate continuously with dual power supplies ranging from ±2.7V to ±8V or a single supply between +2.7V and +16V. Each switch can handle rail-to-rail analog signals. The off leakage current is only 0.1nA at +25°C or 5nA at +85°C.Upon power-up, all switches are off, and the internal shift registers are reset to zero. The MAX395 is electrically equivalent to two MAX391 quad switches controlled by a serial interface, and is pin compatible with the MAX335.The serial interface is compatible with SPI™/QSPI™ and MICROWIRE™. Functioning as a shift register, it allows data (at DIN) to be clocked in synchronously with the rising edge of clock (SCLK). The shift register's output (DOUT) enables several MAX395s to be daisy chained.All digital inputs have 0.8V to 2.4V logic thresholds, ensuring both TTL- and CMOS-logic compatibility when using ±5V supplies or a single +5V supply.ApplicationsAudio-Signal RoutingAutomated Test Equipment (ATE)AvionicsIndustrial and Process Control SystemsNetworkingSerial Data-Acquisition Systems

The MAX3955 is an 11.3Gbps, highly-integrated, low-power transceiver with dual CDRs, and digital diagnostics monitoring (DDM) designed for next-generation SONET transmission systems. The receiver incorporates a limiting amplifier with loss-of-signal (LOS) circuit. The limiting amplifier features an independent 9.95Gbps to 11.32Gbps CDR. The transmitter incorporates Maxim’s proprietary DC-coupled laser driver interface, an independent 9.95Gbps to 11.32Gbps CDR, and closed-loop control of average laser power.The MAX3955 supports differential AC-coupled signaling with integrated 50Ω terminations at Rx input, Rx output, and Tx input. The Tx output is a DC-coupled 25Ω laser diode interface with dedicated pins for the laser anode (TOUTA) and the laser cathode (TOUTC).An integrated 12-bit analog-to-digital converter (ADC) is utilized to provide digital monitors of internal/external temperature, VCC, and received signal strength indication (RSSI). The MAX3955’s analog monitors and the use of a 2-wire or 3-wire slave interface enables configuration through either a digital-only microcontroller (µC) or through the DS1978 SFP+ controller (future product).The MAX3955 operates from single +3.3V supply and over a -40°C to +95°C temperature range and is available in a standard 5mm x 5mm, 32-pin TQFN-EP package.ApplicationsOC-192 XFP and SFP+ Optical Transceivers

The MAX3956 is an 11.3Gbps, highly-integrated, low-power transceiver with digital diagnostics monitoring (DDM) designed for next-generation Ethernet transmission systems. The receiver incorporates a limiting amplifier and loss-of-signal (LOS) circuit. The limiting amplifier features dual-path architecture optimizing the performance for signals up to 4.25Gbps and up to 11.3Gbps, respectively. The transmitter incorporates Maxim’s proprietary DC-coupled laser driver interface and closed-loop control of laser average power. This part is optimized to enable 0.8W maximum power dissipation target of SFP+ MSA based modules.The MAX3956 supports differential AC-coupled signaling with 50Ω termination at Rx input, Rx output, and Tx input. The Tx output is a DC-coupled 25Ω laser diode interface with dedicated pins for the laser anode (TOUTA) and the laser cathode (TOUTC).An integrated 12-bit analog-to-digital converter (ADC) is utilized to provide digital monitors of internal/external temperature, VCC, and received signal strength indication (RSSI). The MAX3956’s digital monitors and the use of a 2-wire or 3-wire slave interface enables configuration through a digital-only microcontroller (µC).The MAX3956 operates from a single +3.3V supply and over a -40°C to +95°C temperature range and is available in a standard 5mm x 5mm, 32-pin TQFN-EP package.Applications10GBASE-LR SFP+ Optical Transceivers

The MAX396/MAX397 low-voltage, CMOS analog multiplexers (muxes) offer low on-resistance (100Ω max), which is matched to within 6Ω between switches and remains flat over the specified signal range (10Ω max). They also offer low leakage over temperature (input off-leakage current less than 1nA at +85°C) and fast switching speeds (transition time less than 250ns). The MAX396 is a 16-channel device, and the MAX397 is a dual 8-channel device.The MAX396/MAX397 are fabricated with Maxim's low-voltage silicon-gate process. Design improvements yield extremely low charge injection (5pC max) and guarantee electrostatic-discharge (ESD) protection greater than 2000V per Method 3015.7.These muxes operate with a single +2.7V to +16V supply or with ±2.7V to ±8V dual supplies, while retaining CMOS-logic input compatibility and fast switching. The MAX396/MAX397 are pin compatible with the industry-standard MAX306/MAX307, DG406/DG407, and DG506A/DG507A.ApplicationsAudio-Signal RoutingAutomated Test Equipment (ATE)AvionicsBattery-Powered ApplicationsCommunication SystemsIndustrial Process ControlsLow-Voltage Data Acquisition SystemsSample-and-Hold Circuits