link to page 10 link to page 10 OP497APPLICATIONS INFORMATION Extremely low bias current makes the OP497 attractive for use in sample-and-hold amplifiers, peak detectors, and log amplifiers that must operate over a wide temperature range. Balancing 10090 input resistances is not necessary with the OP497. High source resistance, even when unbalanced, only minimally degrades the offset voltage and TCVOS. The input pins of the OP497 are protected against large differential voltage by back-to-back diodes and current-limiting resistors. 10 Common-mode voltages at the inputs are not restricted and 0% 3 may vary over the full range of the supply voltages used. 20mV5µs -03 09 03 0 The OP497 requires very little operating headroom about the Figure 31. Small Signal Transient Response (CLOAD = 1000 pF, AVCL = +1) supply rails and is specified for operation with supplies as low as ±2 V. Typically, the common-mode range extends to within 1 V of either rail. When using a 10 kΩ load, the output typically swings to within 1 V of the rails. 100AC PERFORMANCE90 The ac characteristics of the OP497 are highly stable over its full operating temperature range. Figure 30 shows the unity-gain small signal response. Extremely tolerant of capacitive loading on the output, the OP497 displays excellent response even with 10 1000 pF loads (see Figure 31). 0% 4 2V50µs 03 9- 30 00 100 Figure 32. Large Signal Transient Response (AVCL = +1) 90100% 32 20mV5µs 0 9- 30 00 Figure 30. Small Signal Transient Response (CLOAD = 100 pF, AVCL = +1) V+VOUT2.5kΩ–IN2.5kΩ+IN 31 0 9- V– 30 00 Figure 33. Simplified Schematic Showing One Amplifier Rev. E | Page 10 of 16 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION PIN CONNECTIONS TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION TYPICAL PERFORMANCE CHARACTERISTICS APPLICATIONS INFORMATION AC PERFORMANCE GUARDING AND SHIELDING OPEN-LOOP GAIN LINEARITY APPLICATIONS CIRCUIT PRECISION ABSOLUTE VALUE AMPLIFIER PRECISION CURRENT PUMP PRECISION POSITIVE PEAK DETECTOR SIMPLE BRIDGE CONDITIONING AMPLIFIER NONLINEAR CIRCUITS OUTLINE DIMENSIONS ORDERING GUIDE