mc34844 Freescale Semiconductor, Inc, mc34844 Datasheet
mc34844
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mc34844 Summary of contents
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... Figure 1. Simplified Application Diagram (SM-Bus Mode) * This document contains certain information on a new product. Specifications and information herein are subject to change without notice. © Freescale Semiconductor, Inc., 2008. All rights reserved. Device MC34844EP/R2 Applications • Monitors - inch • Personal Computer Notebooks • GPS Screens • ...
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INTERNAL BLOCK DIAGRAM VIN VDC1 VDC2 VDC3 COMP SLOPE VOUT CK EN M/~S PWM SCK SDA ISET PIN NIN Figure 2. 34844 Simplified Internal Block Diagram 34844 2 INTERNAL BLOCK DIAGRAM LDO BOOST CONTROLLER V SENSE CLOCK/PLL PWM GENERATOR 10 ...
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VIN 2 PGNDB SWB 3 SWA 4 PGNDA 5 6 A0/SEN Exposed Pad Table 1. 34844 Pin Definitions A functional description of each pin can be found in the Functional Pin Description section ...
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PIN CONNECTIONS Table 1. 34844 Pin Definitions (continued) A functional description of each pin can be found in the Functional Pin Description section beginning on Pin Number Pin Name Pin Function 26 SDA Bidirectional 27 SCK Bidirectional 28 VDC1 Output ...
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Table 2. Maximum Ratings All voltages are with respect to ground unless otherwise noted. Exceeding these ratings may cause a malfunction or permanent damage to the device. Ratings ELECTRICAL RATINGS Maximum Pin Voltages A0/SEN (4) I0, I1, I2, I3, I4, ...
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ELECTRICAL CHARACTERISTICS Table 3. Electrical Characteristics Characteristics noted under conditions V PIN & NIN = VDC1, - 40°C ≤ T ≤ 105°C, PGND = 0V, unless otherwise noted. A Characteristic SUPPLY Supply Voltage Supply Current when Shutdown Mode Manual & ...
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Table 3. Electrical Characteristics (continued) Characteristics noted under conditions V PIN & NIN = VDC1, - 40°C ≤ T ≤ 105°C, PGND = 0V, unless otherwise noted. A Characteristic (8) Line Regulation VIN=7.0V to 28V (8) Load Regulation VLED = ...
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ELECTRICAL CHARACTERISTICS Table 3. Electrical Characteristics (continued) Characteristics noted under conditions V PIN & NIN = VDC1, - 40°C ≤ T ≤ 105°C, PGND = 0V, unless otherwise noted. A Characteristic NIN INPUT Voltage to Disable NIN mode NIN Bias ...
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Table 3. Electrical Characteristics (continued) Characteristics noted under conditions V PIN & NIN = VDC1, - 40°C ≤ T ≤ 105°C, PGND = 0V, unless otherwise noted. A Characteristic OVER-VOLTAGE PROTECTION Over-voltage Clamp - OVP Register Table: OVP = Fh ...
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ELECTRICAL CHARACTERISTICS Table 3. Electrical Characteristics (continued) Characteristics noted under conditions V PIN & NIN = VDC1, - 40°C ≤ T ≤ 105°C, PGND = 0V, unless otherwise noted. A Characteristic PWM GENERATOR (12) Input PWM Frequency Range M/~S = ...
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LED backlighting has become very popular for small and medium LCDs, due to some advantages over other backlighting schemes, such as the widely used cold cathode fluorescent lamp (CCFL). The advantages of LED backlighting are low cost, long life, immunity ...
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FUNCTIONAL DESCRIPTION FUNCTIONAL PIN DESCRIPTION A0/SEN Address select, device select pin, or Hardware Over voltage Protection (OVP) Control. CURRENT SET (ISET) Each LED string can drive up to 50mA. The maximum current can be set by using a resistor from ...
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... FUNCTIONAL INTERNAL BLOCK DESCRIPTION MC34844 - Functional Block Diagram Regulators / Power Down 3 Internal Regulators Protection / Failure Detection Over-temperature Protection Over-current Protection Under-voltage Protection Over-voltage Protection LED Open Protection Logic Control Optical and Temperature Control PWM Dimming Serial Interface Control Regulator / Power down ...
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FUNCTIONAL DESCRIPTION FUNCTIONAL INTERNAL BLOCK DESCRIPTION MODE EN Pin Low Manual High Low SM-Bus Low Low Low High High Table 4. Operation Current Consumption Modes BOOST The integrated boost converter operates in non- synchronous mode and integrates ...
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Also the device has a precharge voltage that add 0.5 Volts to the Boost, cycle by cycle of the PWM. It helps the boost to respond faster every time the load turns back on again. CURRENT MIRROR The programmable current ...
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FUNCTIONAL DESCRIPTION FUNCTIONAL INTERNAL BLOCK DESCRIPTION Current on LED Channel (PIN mode) × VPIN ICH RegisterValue [ ] Current A = --------------------------------------------------------------------------------------- - [ RSET ohms Current on LED Channel (NIN mode) × ( 2.048 VNIN ) ICH ...
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FUNCTIONAL DEVICE OPERATION NORMAL MODE In normal operation the 34844 is programed via I drive up to 50mA of current through each one of the LED channels. The 34844 can be configured in master or slave mode as set by ...
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FUNCTIONAL DEVICE OPERATION OPERATIONAL MODES the PIN and NIN pins are enabled to scale the current capability per string and may be disable by setting 2.2V in the corresponding terminal. Also in this mode, the device can be enabled as ...
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Table 5. Write Registers REG / OVP3 OVP2 DPWM7 DPWM6 07 08 STRB CLRFAIL 09 14 ICH0_7 ICH0_6 F0 ICH1_7 ICH1_6 F1 ICH2_7 ICH2_6 F2 ICH3_7 ICH3_6 F3 ICH4_7 ICH4_6 F4 ICH5_7 ...
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FUNCTIONAL DEVICE OPERATION LOGIC COMMANDS AND REGISTERS Table 6. Register Description DEFAULT VALUE REGISTER NAME (HEX PINEN 1 NINEN F OVP[3:0] 0 SETI2C 0 CLRI2C 300 FPWM[17:0] FF DPWM[7:0] 3FF CHEN[9:0] 0 ALL_OFF 0 CLRFAIL 0 STRB ...
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Table 7. Over Voltage Protection REGISTER (HEX) Analog Integrated Circuit Device Data Freescale Semiconductor OVP VALUE (VOLTS ...
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TYPICAL PERFORMANCE CURVES (TA=25°C) LOGIC COMMANDS AND REGISTERS TYPICAL PERFORMANCE CURVES (TA=25°C) 95% 94% 93% 92% 91% 90% 89% 88% 87% 86% 85 Figure 5. Boost efficiency vs Input Voltage 50.50 50.45 50.40 50.35 50.30 50.25 50.20 50.15 ...
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Figure 8. Bias Current vs Input Voltage (Operational Mode) Analog Integrated Circuit Device ...
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TYPICAL PERFORMANCE CURVES (TA=25°C) LOGIC COMMANDS AND REGISTERS 3.12 3.10 3.08 3.06 3.04 3.02 3.00 2. Figure 9. Bias Current vs Input Voltage (Sleep Mode) COMP COMP VOUT VOUT INDUCTOR INDUCTOR CURRENT CURRENT 34844 ...
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Figure 11. Typical Operation Waveforms for FPWM=600Hz, 40% Duty SWA SWA SWB SWB INDUCTOR INDUCTOR CURRENT CURRENT VOUT VOUT (ac coupled) (ac coupled) ILED, CH1 ILED, CH1 Figure 12. Typical Operation Waveforms for FPWM=600Hz, 100% Duty Analog Integrated Circuit Device ...
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TYPICAL PERFORMANCE CURVES (TA=25°C) LOGIC COMMANDS AND REGISTERS Figure 13. Low Duty Dimming Operation Waveforms (FPWM=20KHz, 2LSB) Figure 14. Low Duty Dimming Operation Waveforms (FPWM=20KHz, 1LSB) 34844 26 VCh1 VCh1 VCh1 ISET = 20mA, ISET = 20mA, ISET = 20mA, ...
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VIN = 24V 47uF 47uF + + 2.2uF 2.2uF 2.2uF 2.2uF 2.2uF 2.2uF 0 56pF 56pF 0 VOUT 150K 150K OVP = 55V VIN = 24V 47uF 47uF + + 2.2uF 2.2uF 2.2uF 2.2uF 2.2uF 2.2uF 0 56pF 56pF 0 ...
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TYPICAL APPLICATIONS LOGIC COMMANDS AND REGISTERS VIN = 24V 47uF 47uF + + 2.2uF 2.2uF 2.2uF 2.2uF 2.2uF 2.2uF 5.6K 5.6K 0 56pF 56pF 1.8nF 1.8nF 0 0 A0/SEN (Master) A0/SEN (Slave) Control SDA Unit SCK VIN = 24V 47uF ...
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The following formulas are intended for the calculation of all external components related with the Boost converter and Network compensation. In order to calculate a Duty Cycle, the internal losses of the MOSFET and Diode should be taken into consideration. ...
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TYPICAL APPLICATIONS COMPONENTS CALCULATION G M -------------------------- - C = Comp2 6.28 F × SW Slope Compensation Slope Compensation can be expressed either in terms of Ampers/Second or as Volts/Second, through the use of the transfer resistance. The following formula ...
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RECOMMENDED STACK-UP The following table shows the recommended layer stack- up for the signals to have good shielding and Thermal Dissipation. Table 8. Layer Stacking Recommendations Stack-Up Layer 1 (Top) Signal Layer 2 (Inner 1) Ground Layer 3(Inner 2) Signal ...
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PACKAGING PACKAGE DIMENSIONS For the most current package revision, visit www.freescale.com and perform a keyword search using the “98A” listed below. 34844 32 PACKAGING PACKAGE DIMENSIONS EP SUFFIX 32-PIN 98ASA10800D REVISION O Analog Integrated Circuit Device Data Freescale Semiconductor ...
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Analog Integrated Circuit Device Data Freescale Semiconductor EP SUFFIX 32-PIN 98ASA10800D REVISION O PACKAGING PACKAGE DIMENSIONS 34844 33 ...
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PACKAGING PACKAGE DIMENSIONS 34844 34 EP SUFFIX 32-PIN 98ASA10800D REVISION O Analog Integrated Circuit Device Data Freescale Semiconductor ...
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REVISION DATE DESCRIPTION OF CHANGES 11/2008 • Initial Release 3.0 Analog Integrated Circuit Device Data Freescale Semiconductor REVISION HISTORY REVISION HISTORY 34844 35 ...
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... Freescale Semiconductor was negligent regarding the design or manufacture of the part. Freescale™ and the Freescale logo are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © Freescale Semiconductor, Inc., 2008. All rights reserved. ...