Electronic Components Datasheet Search |
|
OPA333AMDBVREP Datasheet(PDF) 9 Page - Texas Instruments |
|
|
OPA333AMDBVREP Datasheet(HTML) 9 Page - Texas Instruments |
9 / 19 page Achieving Output Swing to the Op Amp Negative Rail V OUT R P = 20kΩ Op Amp V − = Gnd OPA333A V IN V+ = +5V −5V Additional Negative Supply General Layout Guidelines OPA333A-EP ,, OPA2333A-EP www.ti.com ............................................................................................................................................................ SGLS383B – APRIL 2007 – REVISED JUNE 2008 Some applications require output voltage swings from 0 V to a positive full-scale voltage (such as 2.5 V) with excellent accuracy. With most single-supply op amps, problems arise when the output signal approaches 0 V, near the lower output swing limit of a single-supply op amp. A good single-supply op amp may swing close to single-supply ground, but will not reach ground. The output of the OPA333A and OPA2333A can be made to swing to ground, or slightly below, on a single-supply power source. To do so requires the use of another resistor and an additional, more negative, power supply than the op amp negative supply. A pulldown resistor may be connected between the output and the additional negative supply to pull the output down below the value that the output would otherwise achieve (see Figure 2). Figure 2. VOUT Range to Ground The OPA333A and OPA2333A have an output stage that allows the output voltage to be pulled to its negative supply rail, or slightly below, using the technique previously described. This technique only works with some types of output stages. The OPA333A and OPA2333A have been characterized to perform with this technique; however, the recommended resistor value is approximately 20 k Ω. Note that this configuration will increase the current consumption by several hundreds of microamps. Accuracy is excellent down to 0 V and as low as –2 mV. Limiting and nonlinearity occurs below –2 mV, but excellent accuracy returns as the output is again driven above –2 mV. Lowering the resistance of the pulldown resistor allows the op amp to swing even further below the negative rail. Resistances as low as 10 k Ω can be used to achieve excellent accuracy down to –10 mV. Attention to good layout practices is always recommended. Keep traces short and, when possible, use a printed circuit board (PCB) ground plane with surface-mount components placed as close to the device pins as possible. Place a 0.1- µF capacitor closely across the supply pins. These guidelines should be applied throughout the analog circuit to improve performance and provide benefits, such as reducing the electromagnetic interference (EMI) susceptibility. Operational amplifiers vary in their susceptibility to radio frequency interference (RFI). RFI can generally be identified as a variation in offset voltage or dc signal levels with changes in the interfering RF signal. The OPA333A has been specifically designed to minimize susceptibility to RFI and demonstrates remarkably low sensitivity compared to previous-generation devices. Strong RF fields may still cause varying offset levels. Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback 9 Product Folder Link(s): OPA333A-EP OPA2333A-EP |
Similar Part No. - OPA333AMDBVREP |
|
Similar Description - OPA333AMDBVREP |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List 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 |