PA9 should be used where high. has preamplifiers for optimum performance with each detector type. Teledyne. Detector Shunt. Impedance (ohms) 1 to 500

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1 PB October ecommended Preamplifiers Operating Circuit The PA5, PA6 and PA7 have The recommended operating adjustable gain and low noise. circuit for most applications is an Preamplifiers should be picked by the operational amplifier in a negativedetector shunt impedance at the feedback transimpedance optimal operating temperature for a configuration. The feedback circuit converts the detector output current particular application (Table 1. The PA9 should be used where high to a voltage, while the op-amp maintains the detector near zero-volt frequency response and low noise are required. The PA9 may not be for lowest noise. (Figure 1.. suitable for DC applications due to its Because varies significantly high input offset voltage. with temperature, selection of the proper op-amp will depend on the detector operating temperature as well as the desired bandwidth. The feedback resistor F should be at least 1x greater than for best signal-to-noise ratio. Teledyne Judson Preamp Selection vs Shunt Selection Impedance has preamplifiers for optimum performance with each detector type. Teledyne ecommended Shunt For high frequency applications, Judson Preamp Op Amp Impedance (ohms the detector may be reverse ed LT 18, and terminated into a low impedance 1 to 5 PA-5, PA-9 Discrete FET load. Maximum reverse is 1 volt. OP7, (See Figure.. 5 to PA-6, PA-9 Discrete FET OPA111, LF56, PA-7, PA-9 Discrete FET Frequency esponse The feedback resistance F, Table I combined with the detector capacitance and dynamic impedance, determines the frequency response of the system. Capacitance and Detectivity vs Wavelength impedance values are provided on for J1 Series High Speed Operating Circuit the data sheet supplied with each 11 5 C detector. (-8 1 E F 1x IS - Vo IS F + Ios 1 Figure 1. J Vos TE1 C - E ( J1T 11 5 C (-6 E J1T elative Capacitance (% Typical J1 Series Operating Circuit D* (, 1KHz, 1Hz (cm Hz/W J1T 11 C (- J1 C ( Wavelength (µm Figure. (~1Kohm Capacitor.1 to.1 µf (ceramic Coax Cable to Oscilloscope V +5V to +1V J1 Series photodiode L (5ohm 1Kohm 6 8 everse Bias Voltage V (Volts 1 Figure. 1 COMMECE DIVE MONTGOMEYVILLE, PA PHONE: FAX: /6

2 Test Conditions All Teledyne Judson detectors undergo stringent quality control testing before shipment. A test setup (Figure. is used to check J1 Series detectors for responsivity ( and detectivity (D*. Aperture Chopper / Heat Sink Preamp F 5 K Blackbody HSA Assembly Scope Shunt Impedance Effective dynamic impedance of the detector at operating temperature, measured at volts (Figure 5.. Wave Analyzer Digital Multimeter TC5 Temp. Controller Figure. Figure 5. Blackbody esponsivity (BB Defined as the current produced by a detector in response to the radiant power on the detector (amps/watt (Figure 6.. For the test setup, BB is equal to Vout/(HBBADGain where HBB is the blackbody irradiance in watts/cm, AD is the area of the detector in cm, Vout is the rms signal voltage at the output of the preamplifier in volts, and Gain is the gain of the preamplifier in volts/amp. esponse to Incoming Photons A copy of the test data is provided with each detector and includes the following test condition information: Flux Density (H Actual rms total power in watts/cm irradiating the detector surface. Equal to F TBB/As/ d where F is the rms constant of the chopper (.6, is the StefanBoltzman constant, TBB is the blackbody temperature, As is the aperture area and d is the source-to-detector distance. Chopping Frequency Frequency of chopper for modulating the blackbody source signal. Blackbody Temperature Absolute temperature in K of the blackbody source used for response test. Figure 6. Peak esponsivity ( esponsivity in amps/watt at the wavelength of peak response. elated to blackbody responsivity by BBG, where the constant G is the ratio of total blackbody power to the power utilized by the detector. For InSb detectors without filters, G 5.5 and is determined as follows: G-1 1 N(,TBB ( d WBB ( p Background Temperature oom temperature in K. where N(,TBB is the irradiance at in w/cm/µ and WBB is the total blackbody irradiance in w/cm. Temperature Operating temperature of the detector during the test. J1TE esponse vs Wavelength & Temperature esponsivity (A/W C - C -65 C -85 C Figure Wavelength (µm /6

3 Calculating esponse Uniformity For a J1-5AP-M: - S 1-6 % response at center 1 1 Equivalent Circuit Iph IS S -.1V CD VD For a J1-5SP-M: L O A D V - S % response at center 1 1 Iph Current generated by incident photons VD Actual voltage across diode junction CD junction capacitance shunt resistance s series resistance Is Output signal current High ratio of Shunt Impedance to series resistance high uniformity. Output signal current from detector Is is defined as: ( Isignal Iphoton shunt ( - series ( shunt ( For J1-5AP-M Isignal 1.5A/W.5A/W (1-6 1 ( -6 Isignal 1.5A/W 1.1A/W "Light Spot" From Source KT f sh where sh detector shunt resistance or feedback resistance whichever is lower. K Boltzmans Constant (1.8 x 1- joules/ K T Operating Temperature ( K f Noise Equivalent Bandwidth (Hertz sh Shunt esistance (ohms Direction of Spot Scan Across Surface ing Contact mm Active Area Position Series resistance is approx. at contact. Total series resistance is approx. 5-1, approx. 6 nominal. Therefore, response uniformity is a fucntion of the voltage divider in the equivalent circuit and S. Noise due to Capacitance at a frequency For a photovoltaic detector junction capacitance can dominate noise at high frequency. in (Preamp voltage noise floor ( fcd Contact C Contact - C 1% elative esponse Noise due to shunt impedance or noise current Johnson (thermal noise int For J1TE-8B6-M -1 J1 Series Noise 5% Active Area Active Area Position (mm /6

4 -7-5 TD vs - I.5mm e ag -St e ag St mm m.5m m.m m.5m ge 1-Sta.mm V vs I Cooler Hot side 7 C 1 Cooler Voltage V (Volts Temperature Effects Cooling an InAs photodiode reduces noise and improves detectivity. Cooling also increases shunt resistance allowing more of the photocurrent Iph to reach the contact ring. The result is an increase in the diode response. For high-power applications such as pulsed laser detection, cooling is generally not necessary. For sensitive, low-power applications such as temperature measurements, the InAs detector should be cooled or at least temperature-stabilized. Stabilizing the temperature near room temperature will not improve performance, but will prevent changes in detector response due to ambient temperature drift. Cold Side Temperature TD ( C Cooler Current I (Amps Figure 8. Shunt esistance vs Temperature 1M 1K 1K 5µm dia. Figure M 1-8 S mm dia. D - mm dia. - + Temperature ( C + Thermoelectric Cooler Operation Figure 8. shows typical power requirements for the TE1, TE and TE coolers. The built-in thermistor can be used to monitor or control the temperature. Figure 1. shows typical thermistor resistance vs. temperature values. Sensitivity, cutoff wavelength and response uniformity are all functions of temperature. temperature should be optimized for a particular application. esistance (K Shunt esistance ( 1K 1K 1K 1K Temperature ( C Temperature - C -65 C Value (K Min. Typ. Max Figure 1. /6

5 Active Model Number Part Number Size (dia. Operating Temperature Cutoff co (5% (mm (µm J1 Series oom Temperature InAs. 5 J1-18C-5U 1..6 J1-18C-1M 11. J1-5AP-M J1TE1 Series One-Stage Thermoelectrically Cooled InAs J1TE1-7S-5U C.5 J1TE1-7S-1M 65. J1TE1-7S-M J1TE Series Two-Stage Thermoelectrically Cooled InAs 8. 5 J1TE-66D-5U C.5 J1TE-66D-1M 89. J1TE-66D-M J1TE Series Three-Stage Thermoelectrically Cooled InAs J1TE-66D-5U J1TE-66D-1M -65 C. 6 J1TE-66D-M 98. J1TE-66D-M J1TE Series Four-Stage Thermoelectrically Cooled InAs. 5 J1TE-CN-5U C. J1TE-CN-1M. J1TE-CN-M-B LD Shunt V 1mV p Maximum peak and 1KHz Minimum peak and 1KHz (Jones Capacitance (A/W Min. (ohms Typ. (ohms (pw/hz (cmhz W (pf E 9.7E9.5 E LD E1 1.6E1 1.E HS1, CM1 1 K 1.K K.K E1.1E1.1E HS Amp, HS1, CM1, CM Amp 1 6K 1 K 5K.5K K K 1 K 5K E11 1.E1 1 1.E11 1.E HS Amp, HS1, CM1, CM Amp K 5K 6.5K 8 K 5K 1 K E11.1E11.1E HS Amp, HS1, CM1, CM Amp 5AP 1/ 1/ -1 18C.7 to detector plane.6..1 to detector plane Case(- (+ (+ Case(-.5 (nom 8B6 66S Sapphire Window Plane Dim. "A" (nom.1 dia pin circle. dia pin circle 7S Optional Packages and Accessories V V DIMENSION "A" J1TE-66S.1" J1TE-66S.7" Sapphire.55 dia. Window Background Pins Omitted Side View.5 dia. Pin Circle Background Pins Omitted.5 Side View 6 pins on." bolt circle.76 pins.17 dia holes (- ( Cooler(+ Cooler(- (- (+ Bottom View 1. Cooler (+.69 Bottom View Cooler (- 5/6

6 Temperature Controllers The Teledyne Judson Model TC5 power supply and temperature controller provides convenient cooler operation at a range of fixed temperatures. The built-in thermistor is used to stabilize the detector temperature. To operate without automatic temperature control, use a.5v power supply. Beginning with a fixed voltage and low current, gradually increase the current as the detector cools. The thermistor can be used to monitor the detector temperature if desired. Heat Sinking the Thermoelectric Cooler Teledyne Judson thermoelectric coolers dissipate up to 5 watts of power. Heat sinking is necessary to dissipate this power. Teledyne Judson offers the following heat sinks to accomplish this task. HS1 Heat Sink for Teledyne Judson 66S/66G Packages The HS1 heat sink is available for Teledyne Judson Ge, InAs and HgCdTe TE cooled detectors mounted in the 66S and 66G packages. The heat sink is designed to provide easy heat sinking to the customer s bench top or optical system. Typical Setup with TC5 Automatic Temperature Control POWE SUPPLIES S 115/ V DETECTO J1 GAIN SET THEM SET POWE DIVE P/I CONTOLLE THEM SET SENSE THEM INT SET SENSE LIMIT SET SET SENSE LIMIT THEMISTO SENSE THEMISTO AMP Package pin configurations: See Product Outline Drawing supplied with detector. Caution: Observe cooler polarity and max. power rating. TC6 Miniature Temperature Controller SIGNAL GND. TC6 TEC TEMPEATUE CONTOLLE SIGNAL GND. +5 VOLT SUPPLY + TEC MAXIMUM ADJUSTMENT EXT. TEMP. SET ESISTO BIDGE MONITO on 1.75 dia. P T S TEMP. STABILIZED IND. +5 VOLT EF. VS +5 VOLTS PW. GND. TEC CU. MONITO P1 TEC CUSTOME SELECTED TEMPEATUE SET ESISTO DETECTO P TEMP. SET ES. MONITO HSA Heat Sink Assembly for Teledyne Judson Thermoelectrically Cooled s The HSA two-stage thermoelectric cooler and heat sink assembly is available for Teledyne Judson TE cooled detectors. The assembly consists of the specified detector, a thermistor and a two-stage thermoelectric cooler mounted in a hermetic package with heat sink and detachable cables. The Model TC5 temperature controller is specifically designed for 6 Bolt Holes use with the HSA. Equally Spaced DETECTO ASSEMBLY FEA TUES FEATUES Precise Temperature Control Temperature Set with a Single esistor Operates with Most TEC Cooled s LED Temperature Sta bilization Maximum TEC Current Adjustable Amps to Detailed Instruction Manuat Provided Temperature Stability to ±. C Single +5 Volt Power Supply Operation Bridge Monitor TEC Current Monitor Small Size CAUTION: Max. current for the TE, TE and TE is 1. ampere. Max. current for the TE1 is 1. ampere. When using a one stage cooler, a series resistor needs to be installed with the TC to limit the max. current to 1. ampere. Threaded Bushing 7/8-8 UN Thread 1.8 dia. 1. dia. 9 to Plane Output Cable length 15" nominal Front View (Cap emoved 1.78 to Top of Threaded Bushing.5 ref.. ref. TE Cooler Power and Cable length 5" nominal Protective Cap Cooler Cooler + Pin Pin Pin 7 Pin 8 Information in this document is believed to be reliable. However, no responsibility is assumed for possible inaccuracies or omission. Specifications are subject to change without notice. 1 COMMECE DIVE MONTGOMEYVILLE, PA PHONE: FAX: /6