The AD7537 contains two 12-bit current output DACs on one monolithic chip. A separate reference input is provided for each DAC. The dual DAC saves valuable board space， and the monolithic construction ensures excellent thermal tracking. Both DACs are guaranteed 12-bit monotonic over the full temperature range. The AD7537 has a 2-byte （8 LSBs， 4 MSBs） loading structure. It is designed for right-justified data format. The control signals for register loading are A0， A1， CS， WR and UPD. Data is loaded to the input registers when CS and WR are low. To transfer this data to the DAC registers， UPD must be taken low with WR. Added features on the AD7537 include an asynchronous CLR line which is very useful in calibration routines. When this is taken low， all registers are cleared. The double buffering of the data inputs allows simultaneous update of both DACs. Also， each DAC has a separate AGND line. This increases the device versatility; for instance one DAC may be operated with AGND biased while the other is connected in the standard configuration. The AD7537 is manufactured using the Linear Compatible CMOS （LC2 MOS） process. It is speed compatible with most microprocessors and accepts TTL， 74HC and 5 V CMOS logic level inputs.