LM27964SQ-I/NOPB National Semiconductor, LM27964SQ-I/NOPB Datasheet
LM27964SQ-I/NOPB
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LM27964SQ-I/NOPB Summary of contents
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... C com- Extended Li-Ion Input: 2.7V to 5.5V ■ Small low profile industry standard leadless package, LLP 24 : (4mm x 4mm x 0.8mm) ■ LM27964SQ-I LED PWM frequency = 10kHz, LM27964SQ-C LED PWM frequency = 23kHz Applications ■ Mobile Phone Display Lighting ■ Mobile Phone Keypad Lighting ■ ...
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... Ordering Information Order Information Current Source PWM Frequency LM27964SQ-I 10kHz. LM27964SQX-I LM27964SQ-C 23kHz. LM27964SQX-C www.national.com 24 Pin Quad LLP Package NS Package Number SQA24A Pin Descriptions Input voltage. Input range: 2.7V to 5.5V. Charge Pump Output Voltage Flying Capacitor Connections LED Drivers - GroupB LED Driver - KEYPAD ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. V pin voltage IN SCL, SDIO, VIO pin voltages -0. Pin Voltages -0. Dxx POUT Continuous Power Dissipation (Note 3) Junction Temperature (T ) J-MAX Storage Temperature Range ...
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... J-MAX-OP JA www.national.com Condition (Note 12) Gain = 1.5x, No Load All ENx bits = "0" ≤ ≤ 2. 90% steady state OUT LM27964SQ-I LM27964SQ-C ≤ ≤ 2.7V V 5.5V IN ≤ ≤ 2. 2mA LOAD ) is dependent on the maximum operating junction temperature (T ), and the junction-to ambient thermal resistance of the part/package in the application (θ ...
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... Note 7: Junction-to-ambient thermal resistance is highly dependent on application and board layout. In applications where high maximum power dissipation exists, special care must be paid to thermal dissipation issues in board design. For more information, please refer to National Semiconductor Application Note 1187: Leadless Leadframe Package (AN-1187). Note 8: Min and Max limits are guaranteed by design, test, or statistical analysis. Typical numbers are not guaranteed, but do represent the most likely norm. ...
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Typical Performance Characteristics 3.6V 16.9kΩ; C SETA SETB SETK LED Drive Efficiency vs Input Voltage Shutdown Current vs Input Voltage BankA/BankB Diode Current vs Brightness Register Code www.national.com Unless otherwise specified =1µF ...
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BankB Diode Current vs BankB Headroom Voltage Keypad Driver Current vs. Brightness Register Code Keypad Driver Current vs Keypad R Keypad Driver Current vs Input Voltage 20138121 Keypad Diode Current vs Keypad Headroom Voltage 20138114 Resistance SET 20138116 7 20138115 ...
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Circuit Description OVERVIEW The LM27964 is a white LED driver system based upon an adaptive 1.5×/1× CMOS charge pump capable of supplying up to 180mA of total output current. With three separately controlled banks of constant current sinks, the LM27964 ...
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After the START condition, the master sends a chip ad- dress. This address is seven bits long followed by an eighth bit which is a data direction bit (R/W). The LM27964 address is 36h. For the eighth ...
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... The internal PWM frequency for BankA and www.national.com BankB is a fixed 10kHz (LM27964SQ-I) or 23kHz (LM27964SQ-C) depending on the option. The DKEY current sink uses an analog current scaling method to control LED brightness. The brightness levels are 100% (Fullscale), 70%, 40%, and 20% ...
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Excessive power dissipation may also limit output current capability of an application. Total Output Current Capability The maximum output current that can be drawn from the LM27964 is 180mA. Each driver bank has a maximum allotted current per ...
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... National highly recommends a 1:1 ratio between the package and the PCB thermal land. To further enhance thermal con- ductivity, the PCB thermal land may include vias to a ground plane. For more detailed instructions on mounting LLP pack- ages, please refer to National Semiconductor Application Note AN-1187. 12 ...
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Physical Dimensions inches (millimeters) unless otherwise noted SQA24: 24 Lead LLP X1 = 4.0mm X2 = 4.0mm X3 = 0.8mm 13 www.national.com ...
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