CAT4026 6-Channel LED Controller with Fault Diagnostics for Large Panel LED Backlighting http://onsemi.com Description The CAT4026 is a high performance, large panel LED controller designed to control six constant current high voltage LED strings. Added control circuitry monitors the lowest cathode voltage and generates a feedback control signal to an external Switch Mode Power Supply (SMPS) to provide a low cost and efficient solution for large panel high voltage LED backlighting. Each LED channel current is accurately matched and controlled by sensing an external resistor in series with a low cost bipolar power transistor. This allows current and heat dissipation concerns to be mitigated from the CAT4026 device package. For added system reliability, both Open−Cathode−Anode (OCA) and Shorted−Cathode−Anode (SCA) fault detection circuitry has been included along with independent Fault flag logic outputs for diagnostic purposes. LED current dimming in all six channels can be precisely controlled by either a Pulse Width Modulation signal via the PWM input pin or by an analog dimming voltage applied at the ANLG pin. In addition the ANLG pin provides a convenient method for limiting the overall maximum power dissipation in the event of excessive LED shorting within any LED string. The device will automatically enter low current shutdown mode by taking the PWM pin low for an extended length of time. SOIC−28 V SUFFIX CASE 751BM PIN CONNECTIONS VDD PWM ANLG BASE1 RSET1 BASE2 RSET2 BASE3 RSET3 OCA C1 N.C. VA N.C. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 (Top View) Features • • • • • • • • • • 6 Channel LED Controller Adaptive Feedback Control to External SMPS for Better Efficiency PWM and Analog Mode Dimming Short Cathode−Anode (SCA) Fault Protection Open Cathode−Anode (OCA) Fault Protection Over−Voltage Protection Thermal Shutdown Protection Automatic Inactivity Power Down Mode SOIC−28L Package These Devices are Pb−Free, Halogen Free/BFR Free and are RoHS Compliant Typical Applications GND SCA VCS BASE6 RSET6 BASE5 RSET5 BASE4 RSET4 FLT−OCA C3 FLT−SCA IFB VC 28 27 26 25 24 23 22 21 20 19 18 17 16 15 MARKING DIAGRAM L3A CAT4026V YYWWXXXX L = Assembly Location Code 3 = Mark “3” for (lead finish Matte−Tin) A = Product Revision: Fixed as “A” CAT4026V = Specific Device Code YY = Production Year (Last Two Digits) WW = Production Week (Two Digits) XXXX = Last Four Digits of Assembly Lot Number ORDERING INFORMATION • LCD−TV LED Backlighting • LED General Lighting Device CAT4026V−T1 (Note 1) Package Shipping SOIC−28 (Pb−Free) 1,000/ Tape & Reel 1. Matte Tin Plated Finish (RoHS−compliant) © Semiconductor Components Industries, LLC, 2011 May, 2011 − Rev. 5 1 Publication Order Number: CAT4026/D CAT4026 LED−LLC VOUT LLC Feedback Circuit 10 k Current Feedback 5V C1 1 nF HI−SENSE LO−SENSE 6 Channel Cathode Bus 5V VDD VC IFB SHORT FLT−SCA OPEN FLT−OCA ANLG 6 Channel Cathode Bus ZvSCA Voltage Feedback Option PWM BAS21LT1 X6−Diodes 1.8 V output (user option) OCA C1 C3 VA SCA VCS X6−Diodes BAS21LT1 CAT4026 BASE[1:6] PWM ANLG Q1 6 RSET[1:6] Q6 6−Channels 6 GND Notes: Q1 to Q6 NPN power transistor MJD340 from ON Semiconductor. External power−derating circuit not shown. R1 R6 Figure 1. Typical Application Circuit Table 1. ABSOLUTE MAXIMUM RATINGS Rating Symbol Value Unit Vin −0.3 to 7 V PWM −0.3 to 7 V or (Vin + 0.3), whichever is lower V −0.3 to 7 V or (Vin + 0.3), whichever is lower V TJ(max) 150 °C Storage Temperature Range TSTG −65 to 150 °C Lead Temperature Soldering Reflow (SMD Styles Only), Pb−Free Versions (Note 3) TSLD 260 °C VDD Voltage Range PWM, ANLG, FLT−OCA, FLT−SCA Voltage Range RSET[x], BASE[x] Maximum Junction Temperature Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. 2. This device series incorporates ESD protection and is tested by the following methods: ESD Human Body Model tested per AEC−Q100−002 (EIA/JESD22−A114) ESD Machine Model tested per AEC−Q100−003 (EIA/JESD22−A115) This device meets latchup tests defined by JEDEC Standard JESD78. 3. For information, please refer to our Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. Table 2. THERMAL CHARACTERISTICS Rating Symbol Value RθJA RψJC 79 23 Thermal Characteristics, SOIC−28 Thermal Resistance, Junction−to−Air (Note 4) Thermal Resistance, Junction−to−Case (Note 4) Unit °C/W 4. Values based on copper area of 645 mm2 (or 1 in2) of 1 oz copper thickness and FR4 PCB substrate. Table 3. OPERATING RANGES Rating Symbol Min Max Rating Input Voltage Vin 4.5 5.5 V Ambient Temperature TA −40 85 °C http://onsemi.com 2 CAT4026 Table 4. ELECTRICAL CHARACTERISTICS (VDD = 5 V, VPWM = VDD, VANLG = 3.3 V, for typical values TA = 25°C, for min/max values TA = −40°C to +85°C; unless otherwise noted.) Test Conditions Parameter RSET[x] pin voltage RSET channel to channel voltage matching (VRSET – VRSETAVR) / VRSETAVR , Nominal current 100 mA per channel RSET device to device matching Symbol Min Typ Max Unit VRSET 0.97 1.00 1.03 V ±0.6 ±2.0 % ±2.5 VRSET−MA T VRSET−D ±0.6 IFB sink current VVCS = 3.6 V IIFB 0.5 mA % VA output voltage VA pin no load VVA 1.8 V VA output resistance 100 mA load RVA 250 W VC output voltage VC pin no load, VCS pin = 3.6 V VVC 1.8 V VC output resistance 100 mA load RVC 360 W VCS pull−up resistance to VDD VPWM = 5 V RVCS 50 kW SHUTDOWN, DISABLE, QUIESCENT CURRENTS Shutdown Current Shutdown mode (PWM low for > 50 ms) IOFF − 50 mA Disable Current VPWM = 0 V, all channels off (PWM low for < 20 ms) IDIS − 1.5 mA Quiescent Current (Note 5) VPWM = 5 V, R1 to R6 = 10 W (100 mA load per channel), application circuit as shown with 0.8 mA BASE pin current per channel IQ − 16 mA 7.6 mA mA No external circuit components present, all BASE[x] and RSET[x] pins floating Short Circuit Supply Current VVCS = GND, all BASE[x] shorted to Ground IQ−MAX − 118 VPWM = 5 V RPWM 80 120 200 VPWM−VIH VPWM−VIL − − 1.2 1.0 − − RANLG 120 150 180 LOGIC I/OS PWM pull−down resistance PWM Input Threshold Voltage VIH Logic High VIL Logic low V ANLG divider network pull−down resistance ANLG to RSET pin voltage ratio (VANLG / VRSET) kW VANLG ≤ 3.0 V, all outputs on, R1−R6 = 10 W VANLG /VRSET 3 kW − OPEN CATHODE−ANODE FAULT DIAGNOSTICS VOCA OCA open−LED threshold voltage 0.97 1.00 1.03 V FLT−OCA pin pull−down voltage Open Cathode Anode fault is active, 5 mA sink current VFLT−OCA 65 mV FLT−OCA open−drain leakage Open Cathode Anode fault is inactive IFLT−OCA 0.2 mA FLT−OCA fault delay Delay between OCA fault and FLT−OCA active TFLT−OCA 1 ms ISCA−ON 1.3 mA SHORT CATHODE−ANODE FAULT DIAGNOSTICS SCA fault detection threshold sink current FLT−SCA transitions to active state (low) SCA fault cleared threshold sink current FLT−SCA transitions to inactive state (high) ISCA−OFF 0.4 mA FLT−SCA pin pull−down voltage Short Cathode Anode fault is active, 5 mA sink current VFLT−SCA 65 mV FLT−SCA fault delay Delay between SCA fault and FLT−SCA active TFLT−SCA 35 ms FLT−SCA open−drain leakage Short Cathode Anode fault is inactive IFLT−SCA 0.2 mA 5. The quiescent current depends on the external bipolar transistors used (ON Semiconductor MJD340) and more specifically of its DC current gain (hFE). http://onsemi.com 3 CAT4026 Table 4. ELECTRICAL CHARACTERISTICS (VDD = 5 V, VPWM = VDD, VANLG = 3.3 V, for typical values TA = 25°C, for min/max values TA = −40°C to +85°C; unless otherwise noted.) (continued) Parameter Test Conditions Symbol Min Typ Max Unit TIMING PWM Enable Time VPWM = 0 V to VDD Iout = 0 mA to 90% of Iout(nom) tEN 800 ns PWM Disable Time VPWM = VDD to 0 V Iout = Iout(nom) to 10% of Iout(nom) tDIS 1 ms Turn−off Shutdown Time, PWM falling to shutdown VPWM = 5 V to 0 V Iout = Iout(nom) to shutdown mode tOFF 25 ms tCC 50 ns Channel to channel turn on and turn off delay (staggering) THERMAL SHUTDOWN Thermal Shutdown Temperature TSD − 150 − °C Thermal Shutdown Hysteresis TSH − 20 − °C Toff SHUTDOWN LOGIC IS RESET PWM SHUTDOWN Tdis Ten 90% LED CURRENT SHUTDOWN 0 mA ILED = 1 V / RSET 10% 0 mA VDD QUIESCENT CURRENT SHUTDOWN 0 mA SHUTDOWN 0 mA Figure 2. Timing Diagram http://onsemi.com 4 CAT4026 TYPICAL PERFORMANCE CHARACTERISTICS (VDD = VPWM = 5 V, VANLG = 3.3 V, TAMB = 25°C unless otherwise specified.) 1.4 16 PWM VOLTAGE (V) QUIESCENT CURRENT (mA) VIH 1.2 1.0 VIL 0.8 0.6 0.4 0.2 0 −40 −10 20 50 80 110 125°C 80°C 4 4.50 4.75 5.00 5.25 5.50 Figure 3. PWM Threshold Voltage vs. Temperature Figure 4. Quiescent Current vs. Temperature 1.02 RSETX = 1 kW 1.01 0.8 RSET VOLTAGE (V) IFB DRIVE CURRENT (mA) 8 VDD VOLTAGE (V) 0.7 0.6 0.5 0.4 0.3 0.2 1.00 0.99 0.98 0.97 0.96 2.0 2.5 3.0 3.5 4.0 0.95 −40 4.5 −10 20 50 80 110 VCS VOLTAGE (V) TEMPERATURE (°C) Figure 5. IFB Sink Current vs. VCS Voltage Figure 6. RSET Voltage vs. Temperature 120 140 1.0 0.8 100 80 MATCHING (%) LED BRIGHTNESS (%) −40°C TEMPERATURE (°C) 0.9 60 40 20 0 25°C 0 140 1.1 1.0 0.1 0 12 0 1 2 3 0.6 Ch2 0.4 Ch6 0.2 Ch4 0 −0.2 Ch5 −0.4 Ch1 −0.6 Ch3 −0.8 −1.0 4 3 6 9 12 15 18 ANLG VOLTAGE (V) CATHODE VOLTAGE (V) Figure 7. LED Brightness vs. ANLG Voltage Figure 8. Matching Channel−to−Channel vs. Cathode Voltage http://onsemi.com 5 21 CAT4026 TYPICAL PERFORMANCE CHARACTERISTICS (VDD = VPWM = 5 V, VANLG = 3.3 V, TAMB = 25°C unless otherwise specified.) 30 OCA VOLTAGE (V) 0.99 SHUTDOWN TIME (ms) 1.00 25°C −40°C 0.98 80°C 0.97 125°C 0.96 0.95 4.50 4.75 5.00 5.25 29 28 25°C 27 80°C 125°C 26 25 5.50 −40°C 4.50 4.75 5.00 5.25 5.50 VDD VOLTAGE (V) VDD VOLTAGE (V) Figure 9. OCA Threshold Voltage vs. Temperature Figure 10. Shutdown Time vs. Temperature 110 100 90 Dropout LED BRIGHTNESS (%) QUIESCENT CURRENT (mA) 100 80 70 60 50 40 30 Normal Regulation 20 10 0 4.50 4.75 5.00 5.25 80 60 40 20 0 5.50 0 20 40 60 80 VDD VOLTAGE (V) PWM DUTY CYCLE (%) Figure 11. Quiescent Current vs. Supply Voltage (Note 6) Figure 12. LED Brightness vs. PWM Duty Cycle 100 6. At initial power up, the CAT4026 will draw a higher quiescent current equal to the “dropout” current until it reaches normal regulation. http://onsemi.com 6 CAT4026 TYPICAL PERFORMANCE CHARACTERISTICS (VDD = VPWM = 5 V, VANLG = 3.3 V, TAMB = 25°C unless otherwise specified.) Figure 13. LED Current Transient During PWM Dimming Figure 14. ANLG Transient, 20% to 80% Brightness Figure 15. Open Cathode−Anode Waveform Figure 16. Short Cathode−Anode Waveform http://onsemi.com 7 CAT4026 Table 5. PIN DESCRIPTION Pin # Name Function 1 VDD Supply Bias voltage input for controller 2 PWM Digital PWM input control to globally PWM all channels 3 ANLG ANLG input bias signal to globally adjust full scale brightness. (intended for external power derating circuit for SCA conditions) 4, 6, 8, 21, 23, 25 BASE [1:6] Base drive connection for external channel high voltage BJT 5, 7, 9, 20, 22, 24 RSET [1:6] Current setting resistor for LED channel (Full Scale Brightness of 1 V) 10 OCA 11 C1 12 N.C. 13 VA 14 N.C. 15 VC Cathode voltage with compensation (divided by 2 and buffered). Leave floating if not used. 16 IFB Current sink feedback (1 mA max) used with external circuit to control of LED Anode supply voltage 17 FLT−SCA 18 C3 19 FLT−OCA 26 VCS Lowest LED Cathode sense input (connect to sensing diode anodes) 27 SCA Highest LED Cathode sense input (connect to external high voltage transistor and zener/diode network) 28 GND Ground reference for all pins Open Cathode Anode over−voltage threshold trigger input (sets maximum allowed LED Anode voltage, 1 V trigger) LED Anode capacitor Do not connect, leave floating Internal cathode reference voltage (divided by 2 and buffered to 1.8 V). Intended to provide reference bias for external circuitry, such as the power derating operational amplifier. Do not connect, leave floating Shorted Cathode−Anode Fault output logic signal (open−drain, active low) indicating presence of excessive cathode voltage Connect pin to GND Open Cathode−Anode Fault output logic signal (open−drain, active low) indicating an Open−channel condition http://onsemi.com 8 CAT4026 Pin Functions VDD The VDD input is the positive supply to the devices. VDD should be nominally 5 V. Each RSET pin contains internal compensating circuitry to eliminate the operating base current, thereby maintaining extremely accurate LED matching on all channels. PWM FLT−OCA The PWM control input provides multiple functions. When the first rising edge is applied to PWM input, the CAT4026 will immediately power−up and remain powered up until the PWM input has been held low for at least typically 25 ms, at which point the device will enter full shutdown mode and draw zero current. When PWM is active (high level), all LED channels are enabled. When PWM is inactive (low level), all LED channels are disabled. For PWM dimming frequencies in the 300 Hz range, duty cycles as low as 0.1% are supported. An internal pull−down resistor (120 kW typical) exists on the PWM input. PWM logic high and low detection levels are typically set at 1.2 V and 1.0 V respectively. The FLT−OCA flag output is active low (open−drain) and is latched whenever an Open Cathode−Anode fault condition has been detected on any LED string. An external pull−up resistor (10 kW) should be connected to FLT−OCA. For systems requiring complete shutdown upon detection of any open−LED channel, the FLT−OCA output can be used to drive the shutdown control of the LED power supply. For systems which must continue operation under open−LED channels, the FLT−OCA should only be used for diagnostic purposes (not for system shutdown). The FLT−OCA is cleared upon power−down of the CAT4026 device. FLT−SCA ANLG The FLT−SCA flag output is active low (open−drain) and becomes active whenever any LED cathode terminal exceeds a user programmed voltage level (at the SCA pin, set by an external zener diode). An external pull−up resistor (10 kW) should be connected to the FLT−SCA pin. For systems requiring complete shutdown upon detection of any faulty LED channel, the FLT−SCA output can be used to drive the shutdown control of the LED power supply. For systems which must continue operation under faulty LED channels, the FLT−SCA should only be used for diagnostic purposes (not for system shutdown). In this case, the FLT−SCA flag can be used to trigger an external power derating circuit reducing the applied voltage at the ANLG control input, thereby reducing the power dissipated in the external bipolar channel transistors. Note: If an Open−LED channel is present, the FLT−SCA flag may become temporary active (depending on the user threshold levels) while the system is diagnosing the Open−channel fault. When the system has eventually cleared (disabled) the open−channel, the fault FLT−SCA will automatically clear itself once the system has stabilized and returned back to normal operating conditions. The ANLG controlled input allows the full scale brightness level of all channels to be globally reduced. When the ANLG control is taken below 3 V, the maximum LED brightness will be equal to 1/3 of the ANLG pin voltage. If the ANLG pin is taken above 3 V, it will have no further effect and the brightness will remain at the full scale (100%) setting. An internal resistive network to ground (150 kW typical) exists on the ANLG pin. The external source resistance driving this input should be taken into consideration when controlling the ANLG input. A simple power derating external circuit can be applied to the ANLG pin whenever excessive voltage is present on any LED cathode. If the ANLG control function is not required, the pin should be pulled high (above 3 V) to ensure full scale brightness is maintained. BASE[1:6] The BASE output pin drives the base of the external NPNs to regulate the LED current in the associated string to the preset value. External high−voltage bipolar junction transistors, such as MJD340, are recommended. Operating base currents up to 5 mA can be powered from each of the BASE pins in normal operating conditions. In the event of any BASE pin being shorted directly to GND, internal protection circuitry will limit the drive current to 15 mA (typically). IFB The IFB pin is a pull−down current sink with a drive level determined by the lowest LED cathode voltage as shown below. RSET[1:6] The RSET input pins sense the voltage of the external LED current bias resistors. Each RSET pin is accurately regulated to a voltage of 1.0 V under the full scale brightness condition (ANLG > 3.0 V). VCS Voltage IFB Drive Current (typ) > 4.1 V 0 mA 3.3 V 0.5 mA < 3.1 V 1.0 mA VCS = Vcathode + Vdiode http://onsemi.com 9 CAT4026 External adjustment of LED Anode supply voltage is controlled by the IFB current sink in conjunction with an external feedback circuit. The external circuit should be configured so that 1 mA drive signal will achieve the desired necessary dynamic adjustment range for expected worst case maximum LED string operating voltage range A linear transconductance relationship exists for the drive current (1 mA/V) for Cathode operation between 2.5 V and 3.5 V. If the open−LED function is not used, the OCA pin should be tied to GND. VCS The VCS pin is connected to each LED cathode via a diode array. This pin detects the lowest LED cathode voltage and sets the feedback signaling to allow the SMPS to adjust the LED Anode voltage to the appropriate levels for optimum efficiency (3 V operating point for the minimum cathode voltage on any string). An external high voltage diode array such as BAS21LT is recommended. C1 Connect a capacitor of 1 nF and a 10 kW resistor from the C1 pin to the LED Anode voltage. Capacitor voltage rating must be greater than the highest LED anode voltage. VA The VA output pin is optional and allows the user to power an external feedback control circuit for setting the common LED Anode operating voltage level. This output is a buffered voltage signal, which tracks 50% of the internal reference being used to control and set the nominal operating level of the lowest LED Cathode string voltage. An internal source impedance of 250 W is present on this output and the nominal voltage is set to 1.8 V (thermal compensation exists to cancel out the external sensing diode temperature coefficient present on the VCS pin). C3 Connect pin to GND. SCA The SCA pin is used to detect a severe mismatch in LED string voltage, such as the occurrence of an Anode−Cathode short. The SCA pin is connected to each LED cathode via a diode array and a voltage level translator. The threshold voltage of the detector can be adjusted by using an external Zener diode. A conduction level of 1.5 mA into the SCA pin will trigger a FAULT condition. The FAULT condition will be cleared upon the conduction current level falling below 0.5 mA and normal operation will resume. VC The VC pin is a buffered voltage signal, which tracks 50% of the voltage level present at the VCS input pin (i.e. the VC voltage is determined by the lowest operating Cathode voltage present on any LED string). This signal provides a convenient feedback control method for systems which use standalone converters to generate the LED Anode supply voltage (as opposed to a current feedback option). An external suitable resistive divider, at the VC pin, can be used to directly control the feedback input of the standalone converter. During shutdown mode, the VC pin is forced into high impedance mode, while during normal operation an output source impedance of 360 W is present on the VC pin. OCA The OCA input is used to detect and protect against abnormally high LED Anode condition. An external resistive divider connected to the OCA pin, from the LED Anode voltage, will trigger a FLT−OCA condition once the OCA input level exceeds 1.0 V. Any open−LED channel will automatically be disabled and removed from the feedback loop when OCA is triggered. This method provides an auto−recovery feature for the system to resume normal operation ensuring only the ‘good’ LED channels are included in the feedback loop. http://onsemi.com 10 CAT4026 Simplified Block Diagram CH[1:6] ANLG − 100 k CH−BIAS + (1 V−CLAMP) + 15 mA−max BASE[1:6] − 50 k RSET[1:6] SHUTDOWN TIMER ENABLE LATCHED NOT−LATCHED PWM SHORT DETECT SCA FLT−SCA CH−PWM FAULT DETECT OPEN SHORT + OCA FLT−OCA − 1 mA_max − 1V IFB1 + 1 mA/V 4.1 V + − 500 mV C3 3.6 V VCS CATHODE DETECT C1 5V 0.5X 1.8 V−nom 0.6 V 3V VDD Ref GND Figure 17. Simplified Block Diagram http://onsemi.com 11 VA VC 3.6 V−nom CH−PWM 1.8 V 0.5X CAT4026 APPLICATION INFORMATION Shorted LED In some cases, the LED string voltage may be different between different strings (channel voltage mismatch). This can be due to LED forward voltage variation or some LEDs becoming shorted in one of the string. One of the string would have a total LED forward voltage lower than other channels. In operation, the cathode voltage of the “shorted” channel will be higher than the other channels causing more power to be dissipated in the external transistor of that channel. Therefore, it is useful to detect this condition and, if needed, derate the LED channel current. The highest cathode voltage is sensed at the SCA pin through a diode−OR network. A zener in series with the diodes, shown in Figure 21, allows to adjust the cathode threshold voltage. Once the SCA pin sinks more than about 1.3 mA, the FLT−SCA fault is triggered and the pin is pulled low. Figure 20 shows a power−up waveform for a threshold voltage at about 45 V. In this example, when the fault is triggered, the LED current decreases from 100 mA to 20 mA. Operation with Open and Shorted LED The CAT4026 can detect both open and shorted LED strings through two diode−OR circuits connected respectively to the VCS and SCA pins, as shown in the application circuit in Figure 1. Open LED When one of the channel becomes open or disconnected, its cathode voltage drops to zero pulled down by the current sensing resistor (R1−R6). The lowest cathode voltage is sensed through a diode at the VCS pin (VCS pin is around 0.6 V above the lowest cathode voltage). This causes the CAT4026 current feedback pin (IFB) current to increase to 1 mA and the power supply to increase the anode voltage VOUT until the OCA pin exceeds 1 V threshold and latches on the FLT−OCA fault (the pin is pulled low). At that time, the CAT4026 disables the open channel (corresponding BASE pin voltage goes to GND) and will ignore that channel until the driver is shutdown. The FLT−OCA pin remains low until the CAT4026 goes to shutdown mode or is powered down. The output voltage VOUT now returns to normal operation level where the lowest cathode voltage is around 3.2 V (VCS pin around 3.6 V). The anode voltage is sensed at the OCA pin through a resistor divider (Ra, Rb) as shown in Figure 21. Figure 20. Shorted LED Channel at Power−up Figure 21 shows a partial application schematic relative to the OCA and SCA fault detection. Figure 18. Open LED at Power−up Figure 21. Schematic for Open/Short Detection Unused LED Channels For applications that require less than 6 LED channels, the unused channel BASE and RSET pins should be left floating. All the other used channels will operate normally. Figure 19. Open LED at Power−up, Base Voltages http://onsemi.com 12 CAT4026 PACKAGE DIMENSIONS SOIC−28, 300 mils CASE 751BM−01 ISSUE O SYMBOL MIN A 2.35 2.65 A1 0.10 0.30 A2 2.05 2.55 b 0.31 0.51 c 0.20 0.33 D 17.78 18.03 E 10.11 10.51 E1 7.34 7.60 E NOM e b e PIN #1 IDENTIFICATION MAX 1.27 BSC h 0.25 0.75 L 0.40 1.27 θ 0º 8º θ1 5º 15º TOP VIEW h D A2 A A1 h q1 q q1 c L E1 SIDE VIEW END VIEW Notes: (1) All dimensions are in millimeters. Angles in degrees. (2) Complies with JEDEC MS-013. http://onsemi.com 13 CAT4026 Example of Ordering Information (Note 9) Prefix Device # Suffix CAT 4026 V − T1 Company ID (Optional) Product Number 4026 Package V: SOIC−28L Lead Finish Blank: Matte Tin Tape & Reel (Note 11) T: Tape & Reel 1: 1,000 / Reel 7. All packages are RoHS−compliant (Lead−free, Halogen−free). 8. The standard lead finish is Matte Tin. 9. The device used in the above example is a CAT4026V−T1 (SOIC−28L, Matte Tin, Tape & Reel, 1,000/Reel). 10. For additional package and temperature options, please contact your nearest ON Semiconductor Sales office. 11. For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specifications Brochure, BRD8011/D. ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. “Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. SCILLC does not convey any license under its patent rights nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner. PUBLICATION ORDERING INFORMATION LITERATURE FULFILLMENT: Literature Distribution Center for ON Semiconductor P.O. Box 5163, Denver, Colorado 80217 USA Phone: 303−675−2175 or 800−344−3860 Toll Free USA/Canada Fax: 303−675−2176 or 800−344−3867 Toll Free USA/Canada Email: [email protected] N. American Technical Support: 800−282−9855 Toll Free USA/Canada Europe, Middle East and Africa Technical Support: Phone: 421 33 790 2910 Japan Customer Focus Center Phone: 81−3−5773−3850 http://onsemi.com 14 ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative CAT4026/D