The TLC271CDR from Texas Instruments is a single LinCMOS programmable low-power operational amplifier in an 8-pin SOIC package. It operates from a single supply of 3 V to 16 V and features a unique bias-select mode that allows the user to trade off power consumption vs. AC performance. Key specs include 1.7-MHz GBW and 3.6-V\/\u00b5s slew rate (high-bias mode), 10-mV max input offset voltage, 60-pA max input bias current, 25-nV\/\u221aHz noise, and 80-dB typical CMRR. Input common-mode range extends 300 mV below the negative rail. Output swings to within 30 mV of the negative rail. Power dissipation 725 mW. Operating temperature range is 0\u00b0C to +70\u00b0C (C-suffix). The ‘R’ suffix denotes tape-and-reel packaging.<\/p>","protected":false},"excerpt":{"rendered":"
The TLC271CDR from Texas Instruments is a single LinCMOS programmable low-power operational amplifier in an 8-pin SOIC package. It operates from a single supply of 3 V to 16 V and features a unique bias-select mode that allows the user to trade off power consumption vs. AC performance. Key specs include 1.7-MHz GBW and 3.6-V\/\u00b5s […]<\/p>\n","protected":false},"author":2,"featured_media":2881,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[19,13],"tags":[],"chip_brand":[138],"class_list":["post-2049","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-analog-linear-ics","category-integrated-circuits-ics","chip_brand-ti"],"acf":{"brief_explanation":"Single LinCMOS op-amp, 3-16V, 1.7MHz GBW, 3.6V\/\u00b5s SR, 60pA Ib, bias-select, SOIC-8, 0~70\u00b0C","date_code":"","package_case":"SOIC-8 (D) (4.9 x 3.9 x 1.58 mm, 1.27mm pitch)","in_stock":450,"datasheet":"https:\/\/www.ti.com\/lit\/ds\/symlink\/tlc271.pdf","price":"$0.62 (1K+ pcs)","product_introduction":"The TLC271CDR is a single operational amplifier from TI's LinCMOS family, built on a silicon-gate CMOS process that provides the input characteristics of CMOS (extremely high input impedance, picoampere bias currents) with better offset voltage stability than conventional metal-gate CMOS op-amps. The LinCMOS technology achieves offset voltage drift of only 0.1 \u00b5V\/month (including the first 30 days), far superior to the 10-100 \u00b5V\/month typical of metal-gate CMOS.\n\nThe key differentiator of the TLC271 is the bias-select mode, controlled by the BIAS pin (pin 8). Three modes are available: High-Bias (BIAS pin to VDD+) for maximum bandwidth (1.7 MHz) and slew rate (3.6 V\/\u00b5s); Low-Bias (BIAS pin to VDD-) for minimum power consumption (typical 10 \u00b5A supply current); and Medium-Bias (BIAS pin open or mid-voltage) for intermediate performance. This allows a single part to serve both high-performance and micropower applications.\n\nIn high-bias mode, the TLC271 offers 1.7-MHz GBW and 3.6-V\/\u00b5s slew rate \u2014 competitive with bipolar op-amps like the LM358 \u2014 while consuming only 675 \u00b5A per channel. In low-bias mode, supply current drops to approximately 10 \u00b5A, suitable for always-on battery-powered circuits, at the expense of reduced bandwidth (~5 kHz) and slew rate.\n\nThe input common-mode voltage range extends 300 mV below the negative rail, enabling the TLC271 to sense signals at or below ground in single-supply systems. The output swings to within 30 mV of the negative rail (under light load), and within 1.2 V of the positive rail. The 60-pA maximum input bias current (0\u00b0C to 70\u00b0C) is orders of magnitude lower than bipolar op-amps, making the TLC271 suitable for high-impedance sensor interfaces (pH probes, photodiodes, piezoelectric transducers).\n\nThree offset voltage grades are available: TLC271 (10 mV), TLC271A (5 mV), and TLC271B (2 mV). The C-suffix denotes commercial temperature range (0\u00b0C to 70\u00b0C); I-suffix covers -40\u00b0C to 85\u00b0C; M-suffix covers -55\u00b0C to 125\u00b0C. The TLC271 is in the process of being discontinued (per TI product page), so new designs should consider the TLC27L1 or TLV271 as replacements.","working_principle":"**LinCMOS Input Stage:** The TLC271 uses a differential input pair of P-channel MOSFETs fabricated on TI's silicon-gate LinCMOS process. The MOSFET gates present virtually infinite DC input impedance (10^12 \u03a9 typical), resulting in picoampere-level input bias current. The silicon-gate process provides more stable threshold voltages than metal-gate CMOS, resulting in the 0.1-\u00b5V\/month offset voltage drift specification.\n\n**Bias-Select Operation:** The BIAS pin (pin 8) controls an internal current mirror that sets the tail current for the differential pair and the bias current for subsequent stages. In high-bias mode (BIAS = VDD+), the tail current is maximized, providing maximum gm (transconductance) and therefore maximum bandwidth and slew rate. In low-bias mode (BIAS = VDD-), the tail current is minimized, reducing gm and bandwidth but cutting supply current to ~10 \u00b5A. This is a unique feature not found in most op-amps.\n\n**CMOS Output Stage:** The output uses a CMOS push-pull (PMOS pull-up, NMOS pull-down) configuration. The NMOS pull-down provides strong sinking capability to the negative rail (within 30 mV), while the PMOS pull-up limits the positive output swing to VDD - 1.2 V. The output can drive loads as low as 600 \u03a9 (limited by output current capability of ~10 mA).\n\n**ESD and Latch-Up Protection:** Internal ESD protection diodes on all pins prevent damage up to 2000 V (HBM per MIL-STD-883C, Method 3015.2). The input\/output structures are designed to withstand -100-mA surge currents without latch-up, a critical concern in CMOS devices.","pin_description":"
| Pin<\/th> | Name<\/th> | Type<\/th> | Description<\/th><\/tr><\/thead> | ||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1<\/td> | NC<\/td> | -<\/td> | No internal connection; leave floating<\/td><\/tr> | ||||||||||||||||||||||||||||
| 2<\/td> | IN-<\/td> | I<\/td> | Inverting input; 60pA max bias current; common-mode range extends -0.3V below negative rail<\/td><\/tr> | ||||||||||||||||||||||||||||
| 3<\/td> | IN+<\/td> | I<\/td> | Non-inverting input; same characteristics as IN-; differential input voltage up to supply voltage<\/td><\/tr> | ||||||||||||||||||||||||||||
| 4<\/td> | VDD-<\/td> | G<\/td> | Negative supply \/ ground; connect to GND for single-supply operation; output swings to within 30mV of this pin<\/td><\/tr> | ||||||||||||||||||||||||||||
| 5<\/td> | NC<\/td> | -<\/td> | No internal connection; leave floating<\/td><\/tr> | ||||||||||||||||||||||||||||
| 6<\/td> | OUT<\/td> | O<\/td> | Amplifier output; swings VDD- +30mV to VDD+ -1.2V; drives up to 10mA; use feedback from OUT to IN- for closed-loop operation<\/td><\/tr> | ||||||||||||||||||||||||||||
| 7<\/td> | VDD+<\/td> | P<\/td> | Positive supply; 3V to 16V; bypass with 0.1\u00b5F ceramic to VDD-<\/td><\/tr> | ||||||||||||||||||||||||||||
| 8<\/td> | BIAS<\/td> | I<\/td> | Bias-select control; connect to VDD+ for high-bias mode (1.7MHz GBW, 675\u00b5A IQ); connect to VDD- for low-bias mode (~10\u00b5A IQ); leave open or mid-voltage for medium-bias mode<\/td><\/tr><\/tbody><\/table>","application_scenarios":"
|