ASDL-3212
IrDA Data Compliant Low Power .52 Mbit/s Infrared Transceiver
Data Sheet
Description
The ASDL-3212 is a new generation ultra small low cost infrared transceiver module which is compliance to IrDA Physical Layers specifications version 1.4 low power from 9.6Kbits/s to 1.152Mbit/s (MIR) with extended link distance. It is IEC825-Class 1 eye safe and designed for very low power consumption which is ideal for battery operated handheld devices. ASDL-3212 features lower pin count through integrated input-output function for interfacing with low voltage 1.5V
General Features
• Operating temperature from -25°C ~ 85°C - Critical parameters are guaranteed over temperature and supply voltage • Vcc Supply 2.4 to 3.6 V • Interface to Various Super I/O and Controller Devices - Support Integrated Input/Output Interface Voltage of 1.5 V • Miniature Package - Height : 1.64 mm - Width : 7.00mm - Depth : 2.73mm • Moisture Level 3 • No Programming required • LED Stuck-High Protection • High EMI Performance • Designed to Accommodate Light Loss with Cosmetic Windows • IEC 825-Class 1 Eye Safe
Applications
• Mobile data communication - Mobile Phones - PDAs - Digital Still Cameras - Printer - Handy Terminals - Industrial and Medical Instrument
Application Support Information
The Application Engineering Group is available to assist you with the application design associated with ASDL3212 infrared transceiver module. You can contact them through your local sales representatives for additional details.
IrDA Features
• Fully Compliant to IrDA 1.4 Physical Layer Low Power Specifications from 9.6 kbit/s to 1.15 Mbit/s - Typical Link Distance > 50cm • Complete shutdown • Low Power Consumption - Low shutdown current - Low idle current
Order Information
Part Number ASDL-322-02 Packaging Type Tape and Reel Package Front Option Quantity 2500
Marking Information
The unit is marked with ‘.PYWWLL’ P Y LL = Product code = 1 digit numeric code for year = 2 digits hexadecimal code for lot information
WW = 2 digits numeric code for work week
Vcc
CX2 CX1 5 6 GnD
Tri-State CMOS buffer
PostAmp
Quantizer
RXD
3
Low Pass Filter
Ambient DC Cancellation
VLED
SD LEDA
4
Regulated Voltage Supply
AGC
R1
1 CX3 r TxD Buffe Stuck One Protection
TXD 2
ASDL-3212 Transceiver Module
Figure 1. Functional Block Diagram
2
PreAmp
PD
Buffer
Recommended Application Circuit Components
Recommended Value R 2.7Ω ± 5%,0.25 watt for 2.4 ≤ VLED < 2.6 3.3Ω ± 5%,0.25 watt for 2.6 ≤ VLED < 2.8 3.9Ω ± 5%,0.25 watt for 2.8 ≤ VLED < 3.0 4.7Ω ± 5%,0.25 watt for 3.0 ≤ VLED < 3.3 5.6Ω ± 5%,0.25 watt for 3.3 ≤ VLED < 3.5 6.8Ω ± 5%,0.25 watt for 3.5 ≤ VLED < 3.8 8.2Ω ± 5%,0.25 watt for 3.8 ≤ VLED < 4.2 0Ω ± 5%,0.25 watt for 4.2 ≤ VLED < 4.7 2Ω ± 5%,0.25 watt for 4.7 ≤ VLED < 5.0 CX2 CX, CX3 00 nF, ± 20%, X7R Ceramic 6.8 mF, ± 20%, Tantalum 7 7 Note
Note: 7. CX1 & CX2 must be placed within 0.7cm of ASDL-3212 to obtain optimum noise immunity
I/O Pins Configuration Table
Pin 2 3 4 5 6 Symbol LEDA TxD RxD SD Vcc GND Description LED Anode IrDA transmitter data input. IrDA receive data Shutdown Supply Voltage Ground Input, Active High Output, Active Low Input, Active High I/O Type Notes Note Note 2 Note 3 Note 4 Note 5 Note 6
6 5 4 3 2 1 Rear View
Figure 2. Pin out
Note: 1. Tied through external resistor, R1, to Vled. Refer to the table below for recommended series resistor value. 2. This pin is used to transmit serial data when SD pin is low. If held high for longer than 50 ms, the LED is turned off. Do NOT float this pin. 3. This pin is capable of driving a standard CMOS or TTL load. No external pull-up or pull-down resistor is required. The pin is in tri-state when the transceiver is in shutdown mode 4. Complete shutdown of IC and PIN diode. Do NOT float this pin. 5. Regulated, 2.4V to 3.6V 6. Connect to system ground.
CAUTION: The BiCMOS inherent to the design of this component increases the component’s susceptibility to damage from electrostatic discharge (ESD). It is advised that normal static precautions be taken in handling and assembly of this component to prevent damage and/or degradation which may be induced by ESD.
3
Absolute Maximum Ratings
Parameter Storage Temperature Junction Temperature Operating Temperature LED Anode Voltage Supply Voltage Input Voltage : TXD, SD/Mode Output Voltage : RXD Peak LED Current DC LED Current Symbol TS TJ TA VLEDA VCC VI VO ILED (PK) ILED (DC) -25 0 0 0 0 Min. -40 Max. +00 +00 +85 6 6 6 6 300 60 Units °C °C °C V V V V mA mA ≤ 20% duty cycle, ≤ 27ns pulse width Fig. 5 Fig. 6 Conditions Ref
Recommended Operating Conditions
Parameter Operating Temperature Supply Voltage Logic Input Voltage for TXD, SD/Mode Receiver Input Irradiance Logic High Symbol TA VCC VIH VIL EIH Min. -25 2.4 .3 0 0.0090 0.0225 Logic Low LED (Logic High) Current Pulse Amplitude Receiver Data Rate Ambient Light EIL ILEDA 0.0096 250 .52 Typ. Max. +85 3.6 .8 0.5 500 500 0.3 mW/cm2 mA Mbit/s See IrDA Serial Infrared Physical Layer Link Specification, Appendix A for ambient levels Units °C V V V mW/cm2 For in-band signals≤ 5.2kbit/s [8] 0.576 Mbit/s ≤ in-band signals ≤.52 Mbit/s [8] For in-band signals [8] VLED = 3.0V, RLED = 4.7W, VI(TxD) ≥ VIH Conditions
Note : [8] An in-band optical signal is a pulse/sequence where the peak wavelength, lp, is defined as 850 ≤ mp ≤ 900 nm, and the pulse characteristics are compliant with the IrDA Serial Infrared Physical Layer Link Specification v1.4.
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Electrical and Optical Specifications
Specifications (Min. & Max. values) hold over the recommended operating conditions unless otherwise noted. Unspecified test conditions may be anywhere in their operating range. All typical values (Typ.) are at 25°C and Vcc set to 3.0V unless otherwise noted.
Receiver
Parameter Viewing Angle Peak Sensitivity Wavelength RxD_IrDA Output Voltage RxD_IrDA Pulse Width (SIR) [9, 0] RxD_IrDA Pulse Width (MIR) [9, ] RxD_IrDA Rise & Fall Times Receiver Latency Time [2] Receiver Wake Up Time [3] Logic High Logic Low Symbol 2q/2 lP VOH VOL tRPW(SIR) tRPW(MIR) tr, tf tL tRW .3 0 .5 250 60 20 200 Min. 30 875 .8 0.4 Typ. Max. Units ° nm V V ms ns ns ms ms q/2 ≤ 5°, CL=9pF, EI = 0 mW/cm2 q/2 ≤ 5°, CL=9pF, EI = 0 mW/cm2 CL=9pF EI = 9.0 mW/cm2 EI = 0 mW/cm2 IOH = -00 mA, EI ≤ 0.3 mW/cm2 Conditions
Infrared (IR) Transmitter
Parameter IR Radiant Intensity IR Viewing Angle IR Peak Wavelength TxD_IrDA Logic Levels TxD_IrDA Input Current Wake Up Time [4] Maximum Optical Pulse Width [5] TXD Pulse Width (SIR) TXD Pulse Width (MIR) TxD Rise & Fall Times (Optical) IR LED Anode On-State Voltage High Low High Low Symbol IEH 2q/2 lP VIH VIL IH IL tTW tPW(Max) tPW(SIR) tPW(MIR) tr, tf VON (LEDA) 2.0 200 70 .6 27 600 40 .3 0 Min. 9 30 870 .8 0.5 0 0 Typ. 80 60 Max. Units mW/sr ° nm V V mA mA ns ms ms ns ns ns V tPW (TXD) =.6ms at 5.2 kbit/s tPW (TXD) =27ns at .52 Mbit/s tPW(TXD) =.6ms at 5.2 kbit/s tPW(TXD) =27ns at .5 Mbit/s ILEDA = 250mA, VI(TxD) ≥ VIH VI ≥ VIH 0 ≤ VI ≤ VIL Conditions ILEDA = 250mA, q/2 ≤ 5°, VI (TxD) ≤ VIH,
Transceiver
Parameters Input Current Supply Current High Low Shutdown Idle (Standby) Symbol IH IL ICC ICC5 445 Min. Typ. Max. 570 Units mA mA mA mA Conditions VI ≥ VIH 0 ≤ VI ≤ VIL VSD > VCC-.3, TA=25°C, no DC ambient VI(TxD) ≤ VIL, EI=0
5
Note: [9] An in-band optical signal is a pulse/sequence where the peak wavelength, lP, is defined as 850 nm ≤ lP ≤ 900 nm, and the pulse characteristics are compliant with the IrDA Serial Infrared Physical Layer Link Specification version 1.4. [10] For in-band signals 115.2 kbit/s where 9 mW/cm2 ≤ EI ≤ 500 mW/cm2. [11] For in-band signals 1.152 Mbit/s where 22 mW/cm2 ≤ EI ≤ 500 mW/cm2. [12] Latency is defined as the time from the last TxD light output pulse until the receiver has recovered full sensitivity. [13] Receiver Wake Up Time is measured from Vcc power ON to valid RxD output. [14] Transmitter Wake Up Time is measured from Vcc power ON to valid light output in response to a TxD pulse. [15] The Max Optical PW is defined as the maximum time which the IR LED will turn on, this, is to prevent the long Turn On time for the IR LED.
2.20 2.10
120 100
Radiant Intensity (mW/sr)
50.0E-3 100.0E-3 150.0E-3 200.0E-3 250.0E-3 300.0E-3 350.0E-3 ILED (A)
2.00 VLED_A (V) 1.90 1.80 1.70 1.60 1.50 1.40 000.0E+0
80 60 40 20 0 000.0E+0
50.0E-3
100.0E-3 150.0E-3 200.0E-3 250.0E-3 300.0E-3 350.0E-3 ILED (A)
Figure 3. VLED_A vs. ILED
Figure 4. Radiant Intensity vs ILED
ILED(PK) Maximum Peak LED Current - mA
I LED(DC) , Maximum DC LED Current - mA
350 300 250 200 150 100 50 0 -40 -20
Max. Permissible Peak LED Current
70 60 50 40 30 20 10 0 -40 -20
Max. Permissible DC LED Current
Rθja = 400degC/W
0 20 40 60 TA - Ambient Temperature - oC
80
100
0 20 40 60 TA - Ambient Temperature - oC
80
100
Figure 5. Maximum Peak LED current vs. ambient temperature. Derated based on TJMAX = 100°C.
Figure 6 Maximum DC LED current vs. ambient temperature. Derated based on TJMAX = 100°C.
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ASDL-3212 (Option -021) Package Dimensions
Figure 7. Package Dimension for ASDL-3212-021
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ASDL-3212 (Option -021) Tape & Reel Dimensions
Unit: mm ∅ 1.5 POLARITY Pin 6: GND 7.5 ± 0.1 16.0 ± 0.2
+0.1 0
4.0 ± 0.1 2.0 ± 0.1 1.75 ± 0.1
Pin 1: LEDA 0.3 ± 0.05 1.85 ± 0.1
7.4 ± 0.1 2.7 ± 0.1 8.0 ± 0.1 Progressive Direction
Empty (40mm min)
Parts Mounted
Leader (400mm min)
Empty (40mm min)
Option # 021
"B" 330
"C" 80
Quantity 2500
Unit: mm Detail A 2.0 ± 0.5 ∅ 13.0 ± 0.5 B C
R1.0 LABEL 21 ± 0.8 Detail A 16.4
+2 0
2.0 ± 0.5
Figure 8. Tape and Reel dimensions
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Moisture Proof Packaging
ASDL-3212 options are shipped in moisture proof package. Once opened, moisture absorption begins. This part is compliant to JEDEC Level 3.
Units in A Sealed Mositure-Proof Package
Package Is Opened (Unsealed)
Environment less than 30 deg C, and less than 60% RH ?
Yes
No Baking Is Necessary
Yes
Package Is Opened less than 168 hours ?
No
Perform Recommended Baking Conditions
No
Figure 9. Baking Conditions Chart
Baking Conditions
If the parts are not stored in dry conditions, they must be baked before reflow to prevent damage to the parts. Package In reels Temp 60 °C Time ≥ 48hours ≥ 4hours
Recommended Storage Conditions
Storage Temperature Relative Humidity 0°C to 30°C below 60% RH
Time from unsealing to soldering
After removal from the bag, the parts should be soldered within 7 days if stored at the recommended storage conditions. If times longer than 7 days are needed, the parts
In bulk 00 °C Baking should only be done once.
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Recommended Reflow Profile
255 MAX 2 60C R3 R4
T - TE MP ER ATUR E (°C)
230 220 200 180 160 120 80 25 0 P1 HE AT UP 50 R1
R2
60 s e c MAX Ab o v e 2 20 C
R5
100 P2 S O LDER P AS TE DRY
150
200 P3 S O LDER RE FLOW
250 P4 C OOL DOW N
300 t-TIME (S EC O NDS )
Process Zone Heat Up Solder Paste Dry Solder Reflow Cool Down
Symbol P, R P2, R2 P3, R3 P3, R4 P4, R5
DT 25°C to 60°C 60°C to 200°C 200°C to 255°C (260°C at 0 seconds max) 255°C to 200°C 200°C to 25°C
Maximum DT/Dtime 3°C/s 0.5°C/s 4°C/s -6°C/s -6°C/s
The reflow profile is a straight-line representation of a nominal temperature profile for a convective reflow solder process. The temperature profile is divided into four process zones, each with different DT/Dtime temperature change rates. The DT/Dtime rates are detailed in the above table. The temperatures are measured at the component to printed circuit board connections. In process zone P1, the PC board and ASDL-3212 castellation pins are heated to a temperature of 160°C to activate the flux in the solder paste. The temperature ramp up rate, R1, is limited to 3°C per second to allow for even heating of both the PC board and ASDL-3212 castellations. Process zone P2 should be of sufficient time duration (60 to 120 seconds) to dry the solder paste. The temperature is raised to a level just below the liquidus point of the solder, usually 200°C (392°F).
Process zone P3 is the solder reflow zone. In zone P3, the temperature is quickly raised above the liquidus point of solder to 255°C (491°F) for optimum results. The dwell time above the liquidus point of solder should be between 20 and 60 seconds. It usually takes about 20 seconds to assure proper coalescing of the solder balls into liquid solder and the formation of good solder connections. Beyond a dwell time of 60 seconds, the intermetallic growth within the solder connections becomes excessive, resulting in the formation of weak and unreliable connections. The temperature is then rapidly reduced to a point below the solidus temperature of the solder, usually 200°C (392°F), to allow the solder within the connections to freeze solid. Process zone P4 is the cool down after solder freeze. The cool down rate, R5, from the liquidus point of the solder to 25°C (77°F) should not exceed 6°C per second maximum. This limitation is necessary to allow the PC board and ASDL-3212 castellations to change dimensions evenly, putting minimal stresses on the ASDL-3212 transceiver.
0
Appendix A: ASDL-3212 (Option -021) SMT Assembly Application Note Solder Pad, Mask and Metal Stencil
Stencil Aperture Metal Stencil for Solder Paste Printing Aperture As Per Land Dimensions t
Land Pattern Solder Mask l PCBA
w
Figure A3. Solder stencil aperture
Stencil thickness, t (mm)
Figure A1. Stencil and PCBA
Aperture size (mm) Length, l .75 +/- 0.05 2.40 +/- 0.05 Width, w 0.55 +/- 0.05 0.55 +/- 0.05
0.27mm 0.0mm
Recommended land pattern
C L
Adjacent Land Keepout and Solder Mask Areas
Adjacent land keepout is the maximum space occupied by the unit relative to the land pattern. There should be no other SMD components within this area. The minimum solder resist strip width required to avoid solder bridging adjacent pads is 0.2mm. It is recommended that two fiducially crosses be placed at mid length of the pads for unit alignment.
0.775
Mounting Center 0.10
1.75 fiducial 0.60 1.425 2.375 Unit: mm 0.95 Pitch
j
h
k
Figure A2. Land Pattern
Solder mask Units: mm
l
Recommended Metal Solder Stencil Aperture
It is recommended that only a 0.11mm (0.004 inch) or a 0.127mm (0.005 inch) thick stencil be used for solder paste printing. This is to ensure adequate printed solder paste volume and no shorting. See the table below the drawing for combinations of metal stencil aperture and metal stencil thickness that should be used. Compared to 0.127mm stencil thickness 0.11mm stencil thickness has longer length in land pattern. It is extended outwardly from transceiver to capture more solder paste volume. See figure 3. Dimension h l k j mm 0.2 3.0 3.0 8.6
Note: Wet/Liquid Photo-imaginable solder resist/mask is recommended.
Figure A4. Adjacent Land Keepout and solder mask areas
Appendix B: PCB Layout Suggestion
The ASDL-3212 is a shieldless part and hence does not contain a shield trace unlike the other transceivers. The effects of EMI and power supply noise can potentially reduce the sensitivity of the receiver, resulting in reduced link distance. The following PCB layout guidelines should be followed to obtain a good PSRR and EM immunity resulting in good electrical performance. Things to note: 1. The ground plane should be continuous under the part. 2. VLED and Vcc can be connected to either unfiltered or unregulated power supply. If VLED and Vcc share the same power supply, CX3 need not be used. The connections for CX1 and CX2 should be connected before the current limiting resistor R1. 3. CX2 is generally a ceramic capacitor of low inductance providing a wide frequency response while CX1 and CX3 are tantalum capacitor of big volume and fast frequency response. The use of a tantalum capacitor is more critical on the VLED line, which carries a high current. 4. Preferably a multi-layered board should be used to provide sufficient ground plane. Use the layer underneath and near the transceiver module as Vcc, and sandwich that layer between ground connected board layers. The diagrams below demonstrate an example of a 4-layer board : The area underneath the module at the second layer, and 3cm in all direction around the module is defined as the critical ground plane zone. The ground plane should be maximized in this zone. The layout below is based on a 2-layer PCB.
Top Layer
Bottom Layer
Top layer Connect the module ground pin to bottom ground layer Layer 2 Critical ground plane zone. Do not connect directly to the module ground pin Layer 3 Keep data bus away from critical ground plane zone Bottom layer (GND)
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Appendix C: General Application Guide for the ASDL-3212 Infrared IrDA® Compliant 1.15Mb/s Transceiver Description
The ASDL-3212 is a low-cost and ultra small infrared transceiver module that provides the interface between logic and infrared (IR) signals for through air, serial, half duplex IR data link. The device is designed to address the mobile computing market such as PDAs, as well as small embedded mobile products such as digital cameras and cellular phones. It is fully compliant to IrDA 1.4 low power specification from 9.6kb/s to 1.15Mb/s. The design of ASDL-3212 also includes the following unique features: • Low passive component count; • Shutdown mode for low power consumption requirement; • Direct interface with Super I/O logic circuit.
Selection of Resistor R1
Resistor R1 should be selected to provide the appropriate peak pulse LED current at different ranges of Vcc as shown under “Recommended Application Circuit Components”.
Interface to the Recommended I/O chip
The ASDL-3212’s TXD data input is buffered to allow for CMOS drive levels. No peaking circuit or capacitor is required. Data rate from 9.6kb/s up to 1.15Mb/s is available at RXD pin. Figures C1 and C2 show how ASDL-3212 fits into a mobile phone and PDA platform respectively.
STN/TFT LCD Panel
Key Pad
LCD Control Touch Panel A/D
Peripherial interface PWM
LCD Backlight Contrast
*ASDL 3212
Mobile Application chipset
IrDA interface
AC97 sound Memory Expansion Logic Bus Driver Memory I/F Baseband I2S controller
PCM Sound
Audio Input
ROM FLASH SDRAM
Power Management
Antenna
Figure C1. Mobile Application Platform
3
C Co olor Display Antenna
LCD Data/Timing Control *ASDL-3212 LCD Interface
External Memory Interface
Peripheral Interface
Flash/ ROM/DRAM OS/Apps Configuration EEPROM
Key Pad Camera Smart Card MMC SD
PDA Application Chipset
USB Reset
McBSP
Wired Connectivity USB Controller
Stereo Audio
Stereo Speaker Stereo Headphone
Microphone Touch Screen Controller
To Battery Fuel Gauge
Figure C2. PDA Platform
The link distance testing was done using typical ASDL3212 units with SMC’s FDC37C669 and FDC37N769 Super I/O controllers. An IR link distance of up to 50 cm was demonstrated.
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Appendix D: Window Design for ASDL-3212 Window Dimension
OPAQUE MATERIAL IR Transparent Window
Y
IR Transparent Window
X K
OPAQUE MATERIAL
Z
A
D
Figure D1. Window Design for ASDL-3212
To ensure IrDA compliance, some constraints on the height and width of the window exist. The minimum dimensions ensure that the IrDA cones angles are met without vignetting. The maximum dimensions minimize the effects of stray light. The minimum size corresponds to a cone angle of 300 and the maximum size corresponds to a cone angle of 600. In figure D1, X is the width of the window, Y is the height of the window and Z is the distance from the ASDL-3212 to the back of the window. The distance from the center of the LED lens to the center of the photodiode lens, K, is 5.1mm. The equations for computing the window dimensions are as follows: X = K + 2*(Z+D)*tanA Y = 2*(Z+D)*tanA
The above equations assume that the thickness of the window is negligible compared to the distance of the module from the back of the window (Z). If they are comparable, Z’ replaces Z in the above equation. Z’ is defined as Z’=Z+t/n where ‘t’ is the thickness of the window and ‘n’ is the refractive index of the window material. The depth of the LED image inside the ASDL-3212, D, is 4.32mm. ‘A’ is the required half angle for viewing. For IrDA compliance, the minimum is 150 and the maximum is 300. Assuming the thickness of the window to be negligible, the equations result in the following table and figures:
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Module Depth
Aperture Width (x, mm) (z) mm 0 2 3 4 5 6 7 8 9 Max 0.09 .24 2.40 3.55 4.7 5.86 7.02 8.7 9.33 20.48 min 7.42 7.95 8.49 9.02 9.56 0.09 0.63 .7 .70 2.24 Aperture height (y, mm) Max 4.99 6.4 7.30 8.45 9.6 0.76 .92 3.07 4.23 5.38 Min 2.32 2.85 3.39 3.92 4.46 4.99 5.53 6.07 6.60 7.4
The recommended minimum aperture width and height is based on the assumption that the center of the window and the center of the module are the same. It is recommended that the tolerance for assembly be considered as well. The minimum window size which will take into account of the assembly tolerance is defined as: X (min + assembly tolerance) = Xmin + 2*(assembly tolerance) (Dimensions are in mm) Y (min + assembly tolerance) = Ymin + 2*(assembly tolerance) (Dimensions are in mm)
Window Material
Almost any plastic material will work as a window material. Polycarbonate is recommended. The surface finish of the plastic should be smooth, without any texture. An IR filter dye may be used in the window to make it look black to the eye, but the total optical loss of the window should be 10% or less for best optical performance. Light loss should be measured at 885 nm. The recommended plastic materials for use as a cosmetic window are available from General Electric Plastics.
25 20 Aperture Width (x) mm 15 10 5 0
Xmax Xmin
Recommended Plastic Materials:
Material # Lexan 4 Lexan 920A Lexan 940A
0 1 2 3 4 5 6 Module Depth (z) mm 7 8 9
Haze 88% 85% 85% % % %
Refractive Index .586 .586 .586
Note: 920A and 940A are more flame retardant than 141.
Recommended Dye: Violet #21051 (IR transmissant above 625mm)
Figure D2. Aperture Height (x) vs. Module Depth (z)
18 16 Aperture Height (Y) mm 14 12 10 8 6 4 2 0 0 1 2 3 4 5 6 Module Depth (z) mm 7 8 9
Shape of the Window
From an optics standpoint, the window should be flat. This ensures that the window will not alter either the radiation pattern of the LED, or the receive pattern of the photodiode. If the window must be curved for mechanical or industrial design reasons, place the same curve on the backside of the window that has an identical radius as the front side. While this will not completely eliminate the lens effect of the front curved surface, it will significantly reduce the effects. The amount of change in the radiation pattern is dependent upon the material chosen for the window, the radius of the front and back curves, and the distance from the back surface to the transceiver. Once these items are known, a lens design can be made which will eliminate the effect of the front surface curve. The following drawings show the effects of a curved window on the radiation pattern. In all cases, the center thickness of the window is 1.5 mm, the window is made of polycarbonate plastic, and the distance from the transceiver to the back surface of the window is 3 mm.
Ymax Ymin
Figure D3. Aperture Height (y) vs. Module Depth (z)
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Flat Window, (First Choice)
Curved Front and Back, (Second Choice)
Curved Front, Flat Back, (Do not use)
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Avago, Avago Technologies, and the A logo are trademarks of Avago Technologies, Limited in the United States and other countries. Data subject to change. Copyright © 2007 Avago Technologies Limited. All rights reserved. AV02-0055EN - January 3, 2007