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A Operational Amplifier Very Low Noise Quad OP470

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aVery Low Noise QuadOperational AmplifierOP470The OP470 offers excellent amplifier matching which is importantfor applications such as multiple gain blocks, low noise instrumentation amplifiers, quad buffers, and low noise active filters.FEATURESVery Low-Noise, 5 nV/ Hz @ 1 kHz MaxExcellent Input Offset Voltage, 0.4 mV MaxLow Offset Voltage Drift, 2 V/ C MaxVery High Gain, 1000 V/mV MinOutstanding CMR, 110 dB MinSlew Rate, 2 V/ s TypGain-Bandwidth Product, 6 MHz TypIndustry Standard Quad PinoutsAvailable in Die FormThe OP470 conforms to the industry standard 14-pin DIP pinout.It is pin compatible with the LM148/149, HA4741, HA5104,and RM4156 quad op amps and can be used to upgrade systemsusing these devices.For higher speed applications, the OP471, with a slew rate of8 V/ms, is recommended.GENERAL DESCRIPTIONThe OP470 is a high-performance monolithic quad operationalamplifier with exceptionally low voltage noise, 5 nV/X/ Hz at1 kHz Max, offering comparable performance to ADI’s industrystandard OP27.The OP470 features an input offset voltage below 0.4 mV,excellent for a quad op amp, and an offset drift under 2 mV/ C,guaranteed over the full military temperature range. Open loopgain of the OP470 is over 1,000,000 into a 10 kW load ensuringexcellent gain accuracy and linearity, even in high gain applications. Input bias current is under 25 nA, which reduces errorsdue to signal source resistance. The OP470’s CMR of over110 dB and PSRR of less than 1.8 mV/V significantly reduceerrors due to ground noise and power supply fluctuations.Power consumption of the quad OP470 is half that of fourOP27s, a significant advantage for power conscious applications. The OP470 is unity-gain stable with a gain bandwidthproduct of 6 MHz and a slew rate of 2 V/ms.PIN CONNECTIONS14–Lead Hermetic Dip(Y–Suffix)14–Lead Plastic Dip(P–Suffix)16–Lead SOIC Package(R–Suffix)OUT A 116 OUT D–IN A 215 –IN D IN A 314 IN DOUT A114OUT D–IN A213–IN DV 4 IN A312 IN D IN B 512 IN CV 411V––IN B 611 –IN C IN B510 IN COUT B 7–IN B69–IN CNC 8OUT B78OUT COP470OP47013 V–10 OUT C9NCNC NO CONNECTSIMPLIFIED SCHEMATICV BIAS–IN INV–REV. AInformation furnished by Analog Devices is believed to be accurate andreliable. However, no responsibility is assumed by Analog Devices for itsuse, nor for any infringements of patents or other rights of third parties thatmay result from its use. No license is granted by implication or otherwiseunder any patent or patent rights of Analog Devices.One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.Tel: 781/329-4700www.analog.comFax: 781/326-8703 Analog Devices, Inc., 2002

OP470–SPECIFICATIONSELECTRICAL CHARACTERISTICS (at V 15 V, T 25 C, unless otherwise noted.)SParameterSymbol ConditionsINPUT OFFSETVOLTAGEVOSINPUT OFFSETCURRENTIOSINPUT BIASCURRENTAOP470A/EOP470FOP470GMin Typ MaxMin Typ MaxMin Typ MaxUnit0.10.40.20.80.41.0mVVCM 0 V3106201230nAIBVCM 0 V62515502560nAINPUT NOISEVOLTAGEenp-p0.1 Hz to 10 Hz(Note 1)802008020080200nVp–pINPUT NOISEVoltage DensityenfO 10 HzfO 100 HzfO 1 kHz(Note 5.55.0nV HzINPUT NOISECurrent DensityinfO 10 HzfO 100 HzfO 1 kHz1.70.70.4LARGE-SIGNALVoltage GainAVOV 10 VRL 10 kWRL 2 kW1000 2300500 1200800 1700400 900800 1700400 900V/mVINPUT VOLTAGERANGEIVR(Note 3) 11 12 11 12 11 12VOUTPUT VOLTAGESWINGVORL 2 kW 12 13 12 13 12 13VCOMMON-MODEREJECTIONCMRVCM 11 V110125100 120100 120dBPOWER SUPPLYRejection RatioPSRRVS 4.5 V to 18 VSLEW RATESRSUPPLY CURRENT(All Amplifiers)ISYNo Load9GAIN BANDWIDTHPRODUCTGBWAV 106CHANNELSEPARATIONCSVO 20 Vp-pfO 10 Hz (Note 1)INPUTCAPACITANCECIN222pFRIN0.40.40.4MWINPUT RESISTANCECommon-ModeRINCM111111GWSETTLING TIMEtS5.56.05.56.05.56.0msINPUT RESISTANCEDifferential-Mode1.70.70.40.56 1.81.4125AV 1to 0.1%to 0.01 %21551.01.4111.7070.45.6296125 1551.01.411pA Hz5.6296125 155mV/VV/ms11mAMHzdBNOTES1Guaranteed but not 100% tested2Sample tested3Guaranteed by CMR test–2–REV. A

OP470(at VS 15 V, –55 C TA 125 C for OP470A, unless otherwise noted.)ELECTRICAL CHARACTERISTICSOP470AParameterSymbolINPUT OFFSET VOLTAGEConditionsMinTypMaxUnitVOS0.140.6mVAVERAGE INPUTOffset Voltage DriftTCVOS0.42mV/ CINPUT OFFSET CURRENTIOSVCM 0 V520nAINPUT BIAS CURRENTIBVCM 0 V1520nALARGE-SIGNALVoltage GainAVOVO 10 VRL 10 kWRL 2 kWINPUT VOLTAGE RANGE*IVROUTPUT VOLTAGE SWINGVOCOMMON-MODEREJECTION7504001600800V/mV 11 12VRL 2 kW 12 13VCMRVCM 11 V100120dBPOWER SUPPLYREJECTION RATIOPSRRVS 4.5 V to 18 VSUPPLY CURRENT(All Amplifiers)ISYNo Load—1.05.6mV/V9.211mANOTE*Guaranteed by CMR testELECTRICAL CHARACTERISTICS(at Vs 15 V, –25 C TA 85 C for OP470E/OP470EF, –40 C TA 85 C for OP470G,unless otherwise noted.)OP470EOP470FOP470GMin Typ MaxMin Typ MaxMin Typ MaxParameterSymbol ConditionsINPUT OFFSETVOLTAGEVOS0.12 0.50.24 1.00.5AVERAGE INPUTOffset Voltage DriftTCVOS0.420.642INPUT OFFSETCURRENTIOSVCM 0 V4207402050nAINPUT BIASCURRENTIBVCM 0 V115020704075nALARGE-SIGNALVoltage GainAVOVO 10 VRL 10 kWRL 2 kWINPUT VOLTAGERANGE*IVROUTPUT VOLTAGESWINGVOCOMMON-MODEREJECTIONPOWER SUPPLYRejection RatioSUPPLY CURRENT(All Amplifiers)mVmV/ C8004001800900600 1400300 700600 1500300 800V/mV 11 12 11 12 11 12VRL 2 kW 12 13 12 13 12 13VCMRVCM 11 V1001209090dBPSRRVS 4.5 V to 18 VISYNo Load—0.75.69.211NOTE*Guaranteed by CMR testREV. 1mA

OP470–SPECIFICATIONSWAFER TEST LIMITS (at V 15 V, 25 C, unless otherwise noted.)sOP470GBCParameterSymbolINPUT OFFSET VOLTAGEVOSINPUT OFFSET CURRENTIOSINPUT BIAS CURRENTConditionsLimitUnit0.8mV MAXVCM 0 V20nA MAXIBVCM 0 V50nA MINLARGE-SIGNALVoltage GainAVOVO 10 VRL 10 kWRL 2 kW800400V/mV MININPUT VOLTAGE RANGE*IVR 11V MINOUTPUT VOLTAGE SWINGVORL 2 kW 12V MINCOMMON-MODEREJECTIONCMRVCM 11 V100dBPOWER SUPPLYREJECTION RATIOPSRRVS 4.5 V to 18 V5.6mV/V MAXSUPPLY CURRENT(All Amplifiers)ISYNo Load11mA MAXNOTE*Guaranteed by CMR testElectrical tests are performed at wafer probe to the limits shown. Due to variations in assembly methods and normal yield loss, yield after packaging is not guaranteed for standard product dice. Consult factory to negotiate specifications based on dice lot qualification through sample lot assembly and testing.–4–REV. A

OP470ABSOLUTE MAXIMUM RATINGS 1Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 VDifferential Input Voltage2 . . . . . . . . . . . . . . . . . . . . . . 1.0 VDifferential Input Current2 . . . . . . . . . . . . . . . . . . . . 25 mAInput Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . Supply VoltageOutput Short-Circuit Duration . . . . . . . . . . . . . . . ContinuousStorage Temperature RangeP, Y Package . . . . . . . . . . . . . . . . . . . . . . –65 C to 150 CLead Temperature Range (Soldering 60 sec) . . . . . . . . . 300 CJunction Temperature (Tj) . . . . . . . . . . . . . –65 C to 150 COperating Temperature RangeOP470A . . . . . . . . . . . . . . . . . . . . . . . . . –55 C to 125 COP470E, OP470F . . . . . . . . . . . . . . . . . . . –25 C to 85 COP470G . . . . . . . . . . . . . . . . . . . . . . . . . . –40 C to 85 C jcUnit14-Lead Hermetic DIP(Y) 9410 C/W14-Lead Plastic DiP(P)7633 C/W16-Lead SOL (S)8823 C/WNOTES1Absolute Maximum Ratings apply to both DICE and packaged parts, unlessotherwise noted.2The OP470’s inputs are protected by back-to-back diodes. Current limitingresistors are not used in order to achieve low noise performance. If differentialvoltage exceeds 1.0 V, the input current should be limited to 25 mA.3 jA is specified for worst case mounting conditions, i.e., jA is specified for devicein socket for TO, CerDIP, PDIP, packages; jA is specified for device soldered toprinted circuit board for SO packages.ORDERING GUIDE IN BPackage OptionsTA 25 CVOS MAX( OP470AY*OP470EYOP470FY* jA3Package TypeV IN A–IN B–IN AOUT BOUT AOUT COUT D–IN D*Not for new design; obsolete April 2002.For military processed devices, please refer to the standardMicrocircuit Drawing (SMD) available atwww.dscc.dla.mil/programs/milspec/default.aspSMD Part NumberADI OP470AYMDAOP470ARCMDAOP470ATCMDA–IN C IN CV– IN DDIE SIZE 0.163 0.106 INCH, 17,278 SQ. mm(4.14 2.69 mm, 11.14 SQ. mm)Figure 1. Dice Characteristics*Not for new designs; obsolete April 2002.CAUTIONESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readilyaccumulate on the human body and test equipment and can discharge without detection. Althoughthe OP470 features proprietary ESD protection circuitry, permanent damage may occur on devicessubjected to high-energy electrostatic discharges. Therefore, proper ESD precautions arerecommended to avoid performance degradation or loss of functionality.REV. A–5–WARNING!ESD SENSITIVE DEVICE

5543I/F CORNER 5Hz4AT 1kHz32110100FREQUENCY – Hz1k 10TA 25 CVS 15V100%246TIME – Secs 20 15TPC 2. Voltage Noise Density vs.Supply Voltage810TPC 3. 0.1 Hz to 10 Hz Noise140TA 25 CVS 15V10INPUT OFFSET VOLTAGE – VVS 15V1.0I/F CORNER 200Hz0.11090SUPPLY VOLTAGE – VTPC 1. Voltage Noise Density vs.Frequency10.01000 501001kFREQUENCY – HzTPC 4. Current Noise Density vs.Frequency120100806040200–75 –5010kCHANGE IN OFFSET VOLTAGE – V1CURRENT NOISE – pA/ HzAT 10Hz–25 02550 75TEMPERATURE – C100TPC 5. Input Offset Voltage vs.Temperature20INPUT OFFSET CURRENT – nA915105876543210123TIME – Mins45TPC 6. Warm-Up Offset Voltage Drift10VS 15VVCM 0VTA 25 CVS 15V901259VS 15VVCM 0VTA 25 CVS 15V8INPUT BIAS CURRENT – nA21s5mV1INPUT BIAS CURRENT – nATA 25 CTA 25 CVS 15VNOISE VOLTAGE – 100nV/DIV109876VOLTAGE NOISE – nV/ HzVOLTAGE NOISE – nV/ HzOP470 –Typical Performance Characteristics765432876510–75 –50–25 02550 75TEMPERATURE – CTPC 7. Input Bias Current vs.Temperature1001250–75 –50–25 025 5075TEMPERSTURE – C100 125TPC 8. Input Offset Current MON-MODE VOLTAGE – V12.5TPC 9. Input Bias Current vs.Common-Mode VoltageREV. 0

OP470100CMR – dB90807060504030TA 25 C8TOTAL SUPPLY CURRENT – mATOTAL SUPPLY CURRENT – mA1101010TA 25 CVS 15VTA 125 CTA –55 C64201001k10kFREQUENCY – Hz100k21MOPEN-LOOP GAIN – dBPSR – dB–PSR6050 PSR403010100908070605040301001k10k 100k 1M 10M 100M–2551600180255075100 1254020010k100k1MFREQUENCY – Hz10MTPC 15. Closed-Loop Gain vs.Frequency880VS 15VTA 25 CRL 10k OPEN-LOOP GAIN – V/mV140060–201k5000100120PHASE MARGIN 58 10TPC 14. Open-Loop Gain vs. FrequencyGAINGAIN – dB3FREQUENCY – HzPHASE SHIFT – DegreesTA 25 CVS 15V15104TA 25 CVS 15V18025205TPC 12. Total Supply Current vs.Supply Voltage1101001k 10k 100k 1M 10M 100MFREQUENCY – HzTPC 13. PSR vs. FrequencyPHASE6TEMPERSTURE – C201002010017801401301201101007082–75 –50 20TPC 11. Total Supply Current vs.Supply VoltageTA 25 C9080 15VS 15VSUPPLY VOLTAGE – VTPC 10. CMR vs. Frequency140130120 10 50CLOSED-LOOP GAIN – dB1014000PHASE MARGIN – Degrees109300020001000GBW7060506 42200–5–101220234 5 6 7 8 9 10FREQUENCY – MHzTPC 16. Open-Loop Gain, PhaseShift vs. FrequencyREV. 000 5 10 15 20SUPPLY VOLTAGE – V 25TPC 17. Open-Loop Gain vs. SupplyVoltage–7–40–75 –50 –2500 25 50 75 100 125 150TEMPERATURE – CTPC 18. Gain-Bandwidth Product,Phase Margin vs. TemperatureGAIN-BANDWIDTH PRODUCT – MHz130120

OP47020TA 25 CVS 15VTHD QUENCY – Hz010010MTPC 19. Maximum Output Swing vs.Frequency1kLOAD RESISTANCE – 010kTPC 20. Maximum Output Voltagevs. Load Resistance3602.5–SR2.0 SRAV 10060CHANNEL SEPARATION – dB1203.01.5150140130120110100908070AV 101001k10k 100k1MFREQUENCY – Hz1000TA 25 CVS 15VVO 20V p-p TO 10kHz1603.5180200400600800CAPACITIVE LOAD – pF170VS 15V2400TPC 21. Small-Signal Overshoot vs.Capacitive Load4.0TA 25 CVS 15VSLEW RATE – V/ s300TA 25 CVS 15VVIN 100mVAV 180POSITIVESWING14401kOUTPUT IMPEDANCE – 100TA 25 CVS 15VOVERSHOOT – %2418MAXIMUM OUTPUT – VPEAK-TO-PEAK AMPLITUDE – V286010M100M1.00255075–75 –50 –25TEMPERATURE – C100 125TPC 23. Slew Rate vs. TemperatureTPC 22. Output Impedance vs.Frequency50101001k10k100kFREQUENCY – Hz1M10MTPC 24. Channel Separation vs.Frequency1DISTORTION – %TA 25 CVS 15VVO 10V p-pRL 2k TA 25 CVS 15VAV 110090TA 25 CVS 15VAV 1100900.10.01AV –101001kFREQUENCY – Hz100%20µs5VAV 10.00110100%50mV0.2µs10kTPC 25. Total Harmonic Distortionvs. FrequencyTPC 26. Large-Signal TransientResponse–8–TPC 27. Small-Signal TransientResponseREV. 0

OP470The total noise is referred to the input and at the output wouldbe amplified by the circuit gain. Figure 4 shows the relationshipbetween total noise at 1 kHz and source resistance. For RS 1 kWthe total noise is dominated by the voltage noise of the OP470.As RS rises above 1 kW, total noise increases and is dominatedby resistor noise rather than by voltage or current noise of theOP470. When RS exceeds 20 kW, current noise of the OP470becomes the major contributor to total noise.5k 500 1/4OP470V1 20V p-p50k 50 1/4OP470Figure 5 also shows the relationship between total noise andsource resistance, but at 10 Hz. Total noise increases morequickly than shown in Figure 4 because current noise is inverselyproportional to the square root of frequency. In Figure 5, currentnoise of the OP470 dominates the total noise when RS 5 kW.V2CHANNEL SEPARATION 20 LOGV1V2/1000Figure 2. Channel Separation Test CircuitFrom Figures 4 and 5 it can be seen that to reduce total noise,source resistance must be kept to a minimum. In applicationswith a high source resistance, the OP400, with lower currentnoise than the OP470, will provide lower total noise. 18V2 1V3100641A5 1V11B79–1VTOTAL NOISE – nV/ TORNOISE ONLYFigure 3. Burn-In Circuit1100The OP470 is a very low-noise quad op amp, exhibiting a typical voltage noise of only 3.2 nV Hz @ 1 kHz. The exceptionallylow-noise characteristics of the OP470 are in part achieved byoperating the input transistors at high collector currents sincethe voltage noise is inversely proportional to the square root ofthe collector current. Current noise, however, is directly proportional to the square root of the collector current. As a result, theoutstanding voltage noise performance of the OP470 is gainedat the expense of current noise performance, which is typical forlow noise amplifiers.OP11OP40010OP471OP470RESISTORNOISE ONLYTOTAL NOISE AND SOURCE RESISTANCEThe total noise of an op amp can be calculated by:En (E n ) (i n R S ) (E t )211002where:1k10kRS – SOURCE RESISTANCE – 100kFigure 5. Total Noise vs. Source Resistance (IncludingResistor Noise) at 10 HzEn total input referred noiseen up amp voltage noisein op amp current noiseet source resistance thermal noiseRS source resistanceREV. A100k100To obtain the best noise performance in a circuit, it is vital tounderstand the relationship between voltage noise (en), currentnoise (in), and resistor noise (et).21k10kRS – SOURCE RESISTANCE – Figure 4. Total Noise vs. Source Resistance (IncludingResistor Noise) at 1 kHzTOTAL NOISE – nV/ HzAPPLICATIONS INFORMATIONVoltage and Current Noise–9–

OP470Figure 6 shows peak-to-peak noise versus source resistance overthe 0.1 Hz to 10 Hz range. Once again, at low values of RS, thevoltage noise of the OP470 is the major contributor to peak-to-peaknoise with current noise the major contributor as RS increases.The crossover point between the OP470 and the OP400 forpeak-to-peak noise is at RS 17 kW.The OP471 is a higher speed version of the OP470, with a slewrate of 8 V/ms. Noise of the OP471 is only slightly higher thanthe OP470. Like the OP470, the OP471 is unity-gain stable.PEAK-TO-PEAK NOISE – nV/ Hz1000OP11OP400TABLE I.SourceDeviceImpedanceStrain gauge 500 WTypically used inlow frequency applications.Magnetictapehead 1500 WLow IB very important to reduceself-magnetization problemswhen direct coupling is used.OP470 IB can be neglected.Magneticphonographcartridges 1500 WSimilar need for low IB in directcoupled applications. OP470will not introduce any selfmagnetization problem.Linear variable 1500 WdifferentialtransformerOP471100OP470CommentsUsed in rugged servo-feedbackapplications. Bandwidth ofinterest is 400 Hz to 5 kHz.For further information regarding noise calculations, see “Minimization of Noisein Op Amp Applications,” Application Note AN-15.RESISTORNOISE ONLYNOISE MEASUREMENTS—PEAK-TO-PEAK VOLTAGE NOISE101001k10kRS – SOURCE RESISTANCE – 100kFigure 6. Peak-To-Peak Noise (0.1 Hz to 10 Hz) vs. SourceResistance (Includes Resistor Noise)For reference, typical source resistances of some signal sourcesare listed in Table I.The circuit of Figure 7 is a test setup for measuring peak-to-peakvoltage noise. To measure the 200 nV peak-to-peak noise specification of the OP470 in the 0.1 Hz to 10 Hz range, the followingprecautions must be observed:1. The device must be warmed up for at least five minutes. Asshown in the warm-up drift curve, the offset voltage typically changes 5 mV due to increasing chip temperature afterpower-up. In the 10-second measurement interval, thesetemperature-induced effects can exceed tens of nanovolts.2. For similar reasons, the device must be well-shielded fromair currents. Shielding also minimizes thermocouple effects.3. Sudden motion in the vicinity of the device can also “feedthrough”to increase the observed noise.R31.24k R15 R25 C12 FOP470DUTOP27ER5909 R4200 C40.22 FR6600k D11N4148D2OP15E1N4148R9306k R810k R1065.4k R1165.4k C30.22 FR144.99k OP15ER135.9k C20.032 FeOUTC51 FR1210k GAIN 50,000VS 5VFigure 7. Peak-To-Peak Voltage Noise Test Circuit (0.1 Hz to 10 Hz)–10–REV. A

OP4704. The test time to measure 0.1 Hz to 10 Hz noise should not exceed 10 seconds. As shown in the noise-tester frequency-responsecurve of Figure 8, the 0.1 Hz corner is defined by only one pole.The test time of 10 seconds acts as an additional pole to eliminate noise contribution from the frequency band below 0.1 Hz.The OP470 is a monolithic device with four identical amplifiers.The noise voltage density of each individual amplifier will match,giving:e OUT 101 Ê 4e n 2 ˆ 101 (2e n )Ë 5. A noise-voltage-density test is recommended when measuringnoise on a large number of units. A 10 Hz noise voltage-densitymeasurement will correlate well with a 0.1 Hz to 10 Hzpeak-to-peak noise reading, since both results are determinedby the white noise and the location of the 1/f corner frequency.NOISE MEASUREMENT—CURRENT NOISE DENSITYThe test circuit shown in Figure 10 can be used to measurecurrent noise density. The formula relating the voltage output tocurrent noise density is:6. Power should be supplied to the test circuit by well bypassedlow noise supplies, e.g. batteries. These will minimize outputnoise introduced via the amplifier supply pins.2in 100(Ê nOUT ˆÁ - 40nV/ HzË G )2RSwhere:GAIN – dB80G gain of 10000RS 100 kW source resistance60R31.24k R15 40R2100k OP470DUT20en OUT TOSPECTRUM ANALYZEROP27E00.01R58.06k 0.11FREQUENCY – Hz10100R4200 Figure 8. 0.1 Hz to 10 Hz Peak-to-Peak Voltage Noise TestCircuit Frequency ResponseGAIN 50,000VS 5VFigure 10. Current Noise Density Test CircuitNOISE MEASUREMENT—NOISE VOLTAGE DENSITYThe circuit of Figure 9 shows a quick and reliable method ofmeasuring the noise voltage density of quad op amps. Eachindividual amplifier is series-connected and is in unity-gain, savethe final amplifier which is in a noninverting gain of 101. Sincethe ac noise voltages of each amplifier are uncorrelated, theyadd in rms fashion to yield:e OUT 101 Ê e nA 2 e nB 2 e nC 2 e nD 2 ˆË R1100 1/4OP4701/4OP4701/4OP470R210k 1/4OP470eOUTTO SPECTRUM ANALYZEReOUT (nV Hz) 101(2en)VS 15VFigure 9. Noise Voltage Density Test CircuitREV. A–11–

OP470R1CAPAC

The OP470 is a high-performance monolithic quad operational amplifier with exceptionally low voltage noise, 5 nV/X/ Hz at 1 kHz Max, offering comparable performance to ADI’s industry standard OP27. The OP470 features an input offset voltage below 0.4 mV, excellent for a quad op amp, and an off