OP490. APPLICATIONS INFORMATION. –18V. BATTERY-POWERED APPLICATIONS. GND. +18V. +15V. V (. 1/4. G A. 1kΩ. OP37. L O. L L. 100Ω. 10kΩ. CE E. –15V. ID X. VIN
link to page 9 OP490APPLICATIONS INFORMATION–18VBATTERY-POWERED APPLICATIONS The OP490 can be operated on a minimum supply voltage of 1.6 V or with dual supplies of ±0.8 V drawing only 60 μA of 141312111098 supply current. In many battery-powered circuits, the OP490 can be continuously operated for hundreds of hours before DC requiring battery replacement, thereby reducing equipment downtime and operating costs. AB High performance portable equipment and instruments frequently use lithium cells because of their long shelf life, light 1234567 weight, and high energy density relative to older primary cells. Most lithium cells have a nominal output voltage of 3 V and are noted for a flat discharge characteristic. The low supply current 9 GND 01 8- requirement of the OP490, combined with the flat discharge 30 +18V 00 characteristic of the lithium cell, indicates that the OP490 can Figure 19. Burn-In Circuit be operated over the entire useful life of the cell. Figure 21 shows the typical discharge characteristic of a 1 Ah lithium cell +15V powering an OP490 with each amplifier, in turn, driving full +15V output swing into a 100 kΩ load. )4+V (1/4EOP490+G A1kΩAT–OP37V2L OA3V–L L100Ω10kΩCE E–15VID X2–15VOVIN+ 1/4HUR DI PV1OP490UL1B-S–20V p-p @ 10HzUM HI IT L 1 0 -02 0250500750100012501500V1 308 CHANNEL SEPARATION = 20 log+V2/1000HOURS 00 1/4 Figure 21. Lithium-Sulphur Dioxide Cell Discharge Characteristic with OP490C OP490 and 100 kΩ Loads –SINGLE-SUPPLY OUTPUT VOLTAGE RANGE In single-supply operation the input and output ranges of the OP490 include ground. This allows true zero-in, zero-out + 1/4 operation. The output stage provides an active pull-down to OP490 around 0.8 V above ground. Below this level, a load resistance of up D– 20 to 1 MΩ to ground is required to pull the output down to zero. 0 8- 30 00 In the region from ground to 0.8 V, the OP490 has voltage gain Figure 20. Channel Separation Test Circuit equal to the data sheet specification. Output current source capability is maintained over the entire voltage range including ground. Rev. E | Page 9 of 16 Document Outline FEATURES GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAMS TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS ELECTRICAL CHARACTERISTICS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION TYPICAL PERFORMANCE CHARACTERISTICS APPLICATIONS INFORMATION BATTERY-POWERED APPLICATIONS SINGLE-SUPPLY OUTPUT VOLTAGE RANGE INPUT VOLTAGE PROTECTION MICROPOWER VOLTAGE-CONTROLLED OSCILLATOR MICROPOWER SINGLE-SUPPLY QUAD VOLTAGE-OUTPUT 8-BIT DAC HIGH OUTPUT AMPLIFIER SINGLE-SUPPLY MICROPOWER QUAD PROGRAMMABLE GAIN AMPLIFIER OUTLINE DIMENSIONS ORDERING GUIDE