数据搜索系统,热门电子元器件搜索 |
|
AD660AN 数据表(PDF) 7 Page - Analog Devices |
|
AD660AN 数据表(HTML) 7 Page - Analog Devices |
7 / 12 page AD660 REV. A –7– BIPOLAR CONFIGURATION The circuit shown in Figure 4a will provide a bipolar output voltage from –10.000000 V to +9.999694 V with positive full scale occurring with all bits ON. As in the unipolar mode, resis- tors R1 and R2 may be eliminated altogether to provide AD660 bipolar operation without any external components. Eliminat- ing these resistors will increase the gain error by 0.50% of FSR in the bipolar mode. 16-BIT LATCH 16-BIT DAC CONTROL LOGIC +10V REF 16-BIT LATCH 20 24 22 21 5 11 12 16 15 14 13 17 18 19 23 AD660 10k 10.05k 10k HBE LBE CS SIN/ DB0 MSB/LSB/ DB1 DB7 S OUT SPAN/ BIP OFF V OUT REF OUT REF IN LDAC CLR SER DGND –V EE +V CC +V LL 1 2 3 4 OUTPUT R2 50 AGND UNI/BIP CLR/ Ω Ω R1 50 Figure 4a. ±10 V Bipolar Voltage Output Gain offset and bipolar zero errors can be adjusted to zero us- ing the circuit shown in Figure 4b as follows: STEP I . . . OFFSET ADJUST Turn OFF all bits. Adjust trimmer R2 to give 10.000000 volts output. STEP II . . . GAIN ADJUST Turn all bits ON and adjust R1 to give a reading of +9.999694 volts. STEP III . . . BIPOLAR ZERO ADJUST (Optional) In applications where an accurate zero output is required, set the MSB ON, all other bits OFF, and readjust R2 for zero volts output. 16-BIT LATCH 16-BIT DAC CONTROL LOGIC +10V REF 16-BIT LATCH 20 24 22 21 5 11 12 16 15 14 13 17 18 19 23 AD660 10k 10.05k 10k HBE LBE CS SIN/ DB0 MSB/LSB/ DB1 DB7 S OUT SPAN/ BIP OFF V OUT REF OUT REF IN LDAC CLR SER DGND –V EE +V CC +V LL 1 2 3 4 OUTPUT R2 100 Ω AGND R1 100 Ω UNI/BIP CLR/ Figure 4b. ±10 V Bipolar Voltage Output with Gain and Offset Adjustment It should be noted that using external resistors will introduce a small temperature drift component beyond that inherent in the AD660. The internal resistors are trimmed to ratio-match and temperature-track other resistors on chip, even though their ab- solute tolerances are ±20% and absolute temperature coeffi- cients are approximately –50 ppm/ °C . In the case that external resistors are used, the temperature coefficient mismatch be- tween internal and external resistors, multiplied by the sensitiv- ity of the circuit to variations in the external resistor value, will be the resultant additional temperature drift. INTERNAL/EXTERNAL REFERENCE USE The AD660 has an internal low noise buried Zener diode refer- ence which is trimmed for absolute accuracy and temperature coefficient. This reference is buffered and optimized for use in a high speed DAC and will give long-term stability equal or supe- rior to the best discrete Zener diode references. The perfor- mance of the AD660 is specified with the internal reference driving the DAC and with the DAC alone (for use with a preci- sion external reference ). The internal reference has sufficient buffering to drive external circuitry in addition to the reference currents required for the DAC (typically 1 mA to REF IN and 1 mA to BIPOLAR OFFSET). A minimum of 2 mA is available for driving external loads. The AD660 reference output should be buffered with an external op amp if it is required to supply more than 4 mA total current. The reference is tested and guaranteed to ±0.2% max error. It is also possible to use external references other than 10 volts with slightly degraded linearity specifications. The recom- mended range of reference voltages is +5 V to +10.24 V, which allows 5 V, 8.192 V and 10.24 V ranges to be used. For ex- ample, by using the AD586 5 V reference, outputs of 0 V to +5 V unipolar or ±5 V bipolar can be realized. Using the AD586 voltage reference makes it possible to operate the AD660 with ±12 V supplies with 10% tolerances. |
类似零件编号 - AD660AN |
|
类似说明 - AD660AN |
|
|
链接网址 |
隐私政策 |
ALLDATASHEETCN.COM |
ALLDATASHEET是否为您带来帮助? [ DONATE ] |
关于 Alldatasheet | 广告服务 | 联系我们 | 隐私政策 | 链接交换 | 制造商名单 All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |