Texas Instruments AMC60704 Optical Controller
Texas Instruments AMC60704 Optical Controller is a highly integrated, low-power controller and analog monitor optimized for electro-absorption modulated laser (EML) applications. The AMC60704 includes four 12-bit current output digital-to-analog converters (IDACs) and four 12-bit voltage output DACs (VDACs) with programmable output ranges. The device also consists of a 12-bit, 1MSPS analog-to-digital converter (ADC) used for internal and external signal monitoring, supply and temperature alarm monitors, and a high-precision internal reference.
The AMC60704 VDACs support positive and negative output-range operation and are capable of sourcing and sinking up to 50mA, making them an excellent choice for biasing optical modulators. The AMC60704 IDACs support a full-scale output range of 200mA with very-low power dissipation. The IDACs eliminate the need for external components to bias laser diodes. In combination, the AMC60704 four VDACs and four IDACs enable accurate biasing of up to four EMLs.
The Texas Instruments AMC60704 includes four input pins multiplexed to the ADC and incorporates a low-latency window comparator. These features make this device an excellent choice for loss-of-signal (LOS) detection and received signal strength indicator (RSSI). The ADC can also measure the voltage at the IDAC pins and the current being sourced or sinked by the VDACs, thus enabling these outputs to be monitored. The AMC60704's low power, high integration, very small size, and wide operating temperature range make this device an excellent choice as an all-in-one control circuit for optical modules.
Features
- Four 12-bit current output DACs (IDACs)
- 200mA full-scale output range
- 300mV at 200mA low supply headroom
- Four 12-bit voltage output DACs (VDACs)
- Selectable full-scale output ranges (–5V, –2.5V, +2.5V and +5V)
- ±50mA high-current drive capability
- Multichannel, 12-bit, 1MSPS SAR ADC
- Four external inputs of 2.5V and 5V ranges
- Four IDAC voltage monitor channels
- Four VDAC current monitor channels
- Programmable sequencer
- Programmable out-of-range alarms
- Internal 2.5V reference
- Supply and temperature fault alarms
- SPI and I2C interfaces (1.7V to 3.6V operation)
- SPI: 4-wire interface
- I2C: Four target addresses
- –40°C to +125°C specified temperature range
Applications
- Optical module
- Intra-DC interconnect (metro)
Simplified Schematic
