PHOTODIODE Si photodiode with preamp S8745, S8746 Photodiode and preamp integrated with feedback resistance and capacitance S8745, S8746 are low-noise light sensors consisting of a large area Si photodiode, op amp, and feedback resistance and capacitance, all integrated into a small package. By simply connecting to a power supply, S8745 and S8746 can be used in low-light-level measurement such as spectrophotometry. Features Applications l Si photodiode for UV to near IR precision photometry l Small package with quartz window l Spectrophotometry l General-purpose optical measurement S8745: TO-5 S8746: TO-8 l FET input operational amplifier with low power dissipation l Built-in Rf=1 G and Cf=5 pF l Variable gain with an externally connected resistor l Low noise and NEP l Guard ring structure for low level signal General ratings / Absolute maximum ratings Type No. S8745 S8746 Dimensional Active area outline/ size Window material * (mm) 2.4 x 2.4 /Q 5.8 x 5.8 /Q Package Number of terminals TO-5 TO-8 10 12 Absolute maximum ratings Supply Reverse Power Operating Storage voltage voltage dissipation temperature temperature (op amp) (photodiode) P Topr Tstg Vcc V4 (V) (V) (mW) (C) (C) 20 5 500 -20 to +60 -30 to +80 Electrical and optical characteristics (Typ. Ta=25 C, Vcc=15 V, RL=1 M9, unless otherwise noted) Type No. Spectral Peak Feedback Feedback response sensitivity resistance capacitance range wavelength Rf Cf (built-in) (built-in) l lp (nm) (nm) S8745 190 to 960 1100 S8746 * Window material Q: quartz glass (GW) (pF) 1 5 Photo sensitivity S (V/nW) Output noise voltage Vn Dark state f=10 Hz Noise equivalent power NEP l=lp (fW/Hz1/2) l=200 f=10 Hz f=20 Hz l=lp (Vrms/Hz1/2) nm 6 11 11 -0.12 -0.52 7 15 15 Output Supply offset Cut-off current voltage frequency Icc Vos fc Dark state Dark state (mV) (Hz) (mA) 4 32 0.3 1 Si photodiode with preamp S8745, S8746 Figure 1 Spectral response S8745, S8746 PHOTO SENSITIVITY (V/nW) -0.6 [Typ.Ta=25 C, Rf=1 G (built-in), Cf=5 pF (built-in)] -0.5 -0.4 -0.3 -0.2 -0.1 0 190 400 600 800 1000 1200 WAVELENGTH (nm) KSPDB0093EA The built-in feedback resistance and capacitance of S8745 and S8746 are 1 G and 5 pF, respectively. This combination provides a sensitivity of about -0.1 to -0.5 V/nW in the wavelength range of 190 to 1100 nm. Figure 2 Gain-frequency characteristics 104 S8746 S8745 +111 M (EXTERNALLY CONNECTED) 103 +11 M (EXTERNALLY CONNECTED) 102 101 100 +1 M (EXTERNALLY CONNECTED) 10-1 10-2 0.01 0.1 1 10 100 CURRENT-TO-VOLTAGE CONVERSION GAIN (M) CURRENT-TO-VOLTAGE CONVERSION GAIN (M) S8745 [Typ. Ta=25 C, Vcc=15 V, Cf=5 pF (built-in), RL=1 M] 104 [Typ. Ta=25 C, Vcc=15 V, Cf=5 pF (built-in), RL=1 M] S8746 103 +111 M (EXTERNALLY CONNECTED) 102 +11 M (EXTERNALLY CONNECTED) 101 100 +1 M (EXTERNALLY CONNECTED) 10-1 10-2 0.01 0.1 1 10 100 FREQUENCY (kHz) FREQUENCY (kHz) KSPDB0199EA KSPDB0198EA The current-to-voltage conversion gain can be varied by connecting an external feedback resistor between pins 4 and 6 for S8745, and between pins 9 and 12 for S8746 (see figure 5). Figure 2 shows the frequency response characteristics of S8745 and S8746 with or without an externally connected feedback resistor. Because S8745 and S8746 have a built-in resistor of 1 G, for example the total feedback resistance will be converted to 100 M by externally connecting a resistor of 111 M. Choose the desired constant according to the incident light level to be detected. Note) If the external feedback resistor is 1 M or less, gain peaking may occur in the frequency response. Therefore, be sure to connect a matched feedback capacitor for phase compensation. 2 Si photodiode with preamp S8745, S8746 Figure 3 Output noise voltage vs. frequency S8745 S8746 [Typ. Ta=25 C, Vcc=15 V, Cf=5 pF (built-in), RL=1 M, dark state] [Typ. Ta=25 C, Vcc=15 V, Cf=5 pF (built-in), RL=1 M, dark state] 100 OUTPUT NOISE VOLTAGE (Vrms/Hz1/2) OUTPUT NOISE VOLTAGE (Vrms/Hz1/2) 100 S8745 10 +111 M (EXTERNALLY CONNECTED) +11 M (EXTERNALLY CONNECTED) 1 0.1 +1 M (EXTERNALLY CONNECTED) 0.01 0.001 0.01 0.1 1 10 100 S8746 +111 M (EXTERNALLY CONNECTED) 10 +11 M (EXTERNALLY CONNECTED) 1 0.1 +1 M (EXTERNALLY CONNECTED) 0.01 0.001 1000 0.01 FREQUENCY (kHz) 0.1 1 10 100 1000 FREQUENCY (kHz) KSPDB0200EA KSPDB0201EA Output noise voltage and NEP (noise equivalent power) characteristics allow you to check whether the device can detect the lowlevel light you want to measure. Since NEP is given by the equation (1) as shown at the right, NEP at wavelengths other than p can be easily calculated from Figure 1 and Figures 4. Note) When S8745 and S8746 are used only with the internal current-to-voltage gain, it is recommended that the "-IN" lead (pin 6 for S8745; pin 9 for S8746) be cut off to a short length in order to reduce the influence of external noise as much as possible. Vn (f) NEP (f, p) * S (p) *** (1) = GI - V (f) * Ssi () S () NEP (f, ) : NEP at frequency and wavelength to be detected NEP (f, p): NEP at peak wavelength (See Figures 4) GI-V(f) : Current-to-voltage conversion gain (See Figure 2) Ssi () : Sensitivity of Si photodiode S () : Sensitivity of S8745 and S8746 (See Figure 1.) S (p) : Sensitivity of S8745 and S8746 at peak wavelength, 0.5 V/nW Vn (f) : Output noise voltage (See Figure 3) NEP (f, ) = Figure 4 NEP vs. frequency S8745 106 [Typ. Ta=25 C, Vcc=15 V, Cf=5 pF (built-in), RL=1 M, dark state, l=lp] NEP (fW/Hz1/2) 104 +111 M (EXTERNALLY CONNECTED) 103 [Typ. Ta=25 C, Vcc=15 V, Cf=5 pF (built-in), RL=1 M, dark state, l=lp] 105 +11 M (EXTERNALLY CONNECTED) +1 M (EXTERNALLY CONNECTED) 104 +11 M (EXTERNALLY CONNECTED) 103 +111 M (EXTERNALLY CONNECTED) 102 102 101 0.001 106 +1 M (EXTERNALLY CONNECTED) 105 NEP (fW/Hz1/2) S8746 S8746 S8745 0.01 0.1 1 10 100 1000 101 0.001 0.01 0.1 1 10 100 1000 FREQUENCY (kHz) FREQUENCY (kHz) KSPDB0202EA KSPDB0203EA 3 Si photodiode with preamp S8745, S8746 Figure 5 External connection example S8745 Vcc+ Rf (EXTERNALLY CONNECTED) 0.1 F TO-5 PACKAGE Rf=1 G (BUILT-IN) Cf=5 pF (BUILT-IN) PHOTODIODE WINDOW (QUARTZ) + RL RL is the input impedance to the next-stage circuit when viewed from the OUT terminal. 0.1 F NC VccKSPDC0042EA S8746 Vcc+ Rf (EXTERNALLY CONNECTED) 0.1 F TO-8 PACKAGE Rf=1 G (BUILT-IN) Cf=5 pF (BUILT-IN) PHOTODIODE WINDOW (QUARTZ) + RL RL is the input impedance to the next-stage circuit when viewed from the OUT terminal. 0.1 F NC VccKSPDC0043EA S8745 and S8746 use a package with the guard ring effect provided. To make it effective during measurement, the package leads (pin 5 for S8745; pins 5 and 11 for S8746) should be connected to the ground line. When a feedback resistor is externally connected, it is necessary to provide a guard ring on the circuit board or to provide a teflon standoff for the leads. Note) A tantalum or ceramic capacitor of 0.1 to 10 F must be connected to the supply voltage leads (pins 3 and 9 for S8745; pins 1 and 4 for S8746) as a bypass capacitor used to prevent the device from oscillation. 4 Si photodiode with preamp S8745, S8746 Figure 6 Dimensional outlines (unit: mm) S8746 14.0 0.2 6.4 0.2 15.2 0.3 8.2 0.1 WINDOW 10.0 0.2 NC NC Vcc+ OUT CASE -IN NC +IN VccPD (CATHODE) 5.08 0.2 5.84 0.2 1.2 MAX. (13.5) 0.45 LEAD 10.16 0.2 0.45 LEAD PHOTOSENSITIVE SURFACE (20) 0.5 MAX. PHOTOSENSITIVE SURFACE 3.45 4.7 WINDOW 3.0 0.1 9.15 0.2 5.1 0.2 S8745 Vcc+ NC NC VccCASE +IN NC NC -IN PD (CATHODE) CASE OUT 5.08 0.2 BOTTOM VIEW 10.16 0.2 BOTTOM VIEW KSPDA0148EA KSPDA0149EA Precautions for Use ESD S8745 and S8746 may be damaged or their performance may deteriorate by such factors as electro static discharge from the human body, surge voltages from measurement equipment, leakage voltages from soldering irons and packing materials. As a countermeasure against electro static discharge, the device, operator, work place and measuring jigs must all be set at the same potential. The following precautions must be observed during use: * To protect the device from electro static discharge which accumulate on the operator or the operator's clothes, use a wrist strap or similar tools to ground the operator's body via a high impedance resistor (1 M). * A semiconductive sheet (1 M to 100 M) should be laid on both the work table and the floor in the work area. * When soldering, use an electrically grounded soldering iron with an isolation resistance of more than 10 M. * For containers and packing, use of a conductive material or aluminum foil is effective. When using an antistatic material, use one with a resistance of 0.1 M/cm2 to 1 G/cm2. Wiring If electric current or voltage is applied in reverse polarity to an electronic device such as a preamplifier, this can degrade device performance or destroy the device. Always check the wiring and dimensional outline to avoid misconnection. Information furnished by HAMAMATSU is believed to be reliable. However, no responsibility is assumed for possible inaccuracies or omissions. Specifications are subject to change without notice. No patent rights are granted to any of the circuits described herein. (c)2003 Hamamatsu Photonics K.K. HAMAMATSU PHOTONICS K.K., Solid State Division 1126-1 Ichino-cho, Hamamatsu City, 435-8558 Japan, Telephone: (81) 053-434-3311, Fax: (81) 053-434-5184, http://www.hamamatsu.com U.S.A.: Hamamatsu Corporation: 360 Foothill Road, P.O.Box 6910, Bridgewater, N.J. 08807-0910, U.S.A., Telephone: (1) 908-231-0960, Fax: (1) 908-231-1218 Germany: Hamamatsu Photonics Deutschland GmbH: Arzbergerstr. 10, D-82211 Herrsching am Ammersee, Germany, Telephone: (49) 08152-3750, Fax: (49) 08152-2658 France: Hamamatsu Photonics France S.A.R.L.: 8, Rue du Saule Trapu, Parc du Moulin de Massy, 91882 Massy Cedex, France, Telephone: 33-(1) 69 53 71 00, Fax: 33-(1) 69 53 71 10 United Kingdom: Hamamatsu Photonics UK Limited: 2 Howard Court, 10 Tewin Road, Welwyn Garden City, Hertfordshire AL7 1BW, United Kingdom, Telephone: (44) 1707-294888, Fax: (44) 1707-325777 North Europe: Hamamatsu Photonics Norden AB: Smidesvagen 12, SE-171 41 Solna, Sweden, Telephone: (46) 8-509-031-00, Fax: (46) 8-509-031-01 Italy: Hamamatsu Photonics Italia S.R.L.: Strada della Moia, 1/E, 20020 Arese, (Milano), Italy, Telephone: (39) 02-935-81-733, Fax: (39) 02-935-81-741 Cat. No. KSPD1054E03 Feb. 2003 DN 5