MAX6974ATL+ Maxim Integrated Products, MAX6974ATL+ Datasheet
MAX6974ATL+
Specifications of MAX6974ATL+
Related parts for MAX6974ATL+
MAX6974ATL+ Summary of contents
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... LED Power Supply ♦ +3.0V to +3.6V Logic Supply ♦ Open-Circuit LED Fault Detection ♦ Optional Watchdog Timer Blanks Display if Interface Fails ♦ Standard -40°C to +125°C Operating Temperature Range PART MAX6974ATL+ MAX6975ATL Exposed paddle. + Denotes a lead-free package. TOP VIEW AGND Applications *EP = EXPOSED PADDLE. ...
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PWM LED Drivers for Message Boards ABSOLUTE MAXIMUM RATINGS (All voltages with respect to GND.) V ........................................................................-0.3V to +4.0V DD R0–R7, G0–G7, B0–B7, MUX0, and MUX1 ...........-0.3V to +8.0V All Other Pins..............................................-0. Continuous Power Dissipation (T = ...
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ELECTRICAL CHARACTERISTICS (continued 3.0V to 3.6V unless otherwise noted. Typical values are MIN MAX PARAMETER SYMBOL Output Slew Time LOADO Output Low Voltage MUX_ Open-Circuit Detection Output Voltage ...
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PWM LED Drivers for Message Boards (V = 3.3V +25°C, unless otherwise noted OPERATING CURRENT CONSUMPTION vs. SUPPLY VOLTAGE 32MHz CLKI CALDAC = 0xFF T = +25° ...
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PIN NAME MUX0 Multiplex 0 Active-Low, Open-Drain Output. Use MUX0 to drive a pnp transistor CLKI+ PWM and Serial-Interface Noninverting Clock LVDS Input 3 CLKI- PWM and Serial-Interface Inverting Clock LVDS Input 4 DIN+ Serial-Interface Noninverting Data LVDS ...
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PWM LED Drivers for Message Boards R LED OUTPUTS EXT. PNP 8-BIT MUX0 R LED DRIVERS I SET OUTPUT R CALDAC R7–R0 8 PWM COUNTERS SYNC 0/1 LOAD OE EN CONTROL ...
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R LED OUTPUTS EXT. PNP 8-BIT MUX0 R LED DRIVERS I SET OUTPUT R CALDAC R7–R0 8 PWM COUNTERS SYNC 0/1 LOAD OE EN CONTROL LOADI SYNC DETECT CLKI DIN D Q1 ...
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PWM LED Drivers for Message Boards Detailed Description The MAX6974/MAX6975 drive 24 nonmultiplexed LEDs or 48 multiplexed LEDs for various indoor and outdoor display applications. The EZCascade serial interface enables large multidriver display panels to be con- structed with ...
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LED-Intensity Control The MAX6974/MAX6975 provide three levels of output current control for LED drive: calibration DACs (CALDACs), global-intensity control, and individual- intensity control. The CALDACs set the port output cur- rent levels, while the global-intensity and individual- intensity controls modulate ...
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PWM LED Drivers for Message Boards (PWM) value. Each output current driver in the R, G, and B ports has a unique 12-bit (MAX6974) or 14-bit (MAX6975) PWM control value providing fine resolution adjustment of average current output. Each ...
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Figure 4 as subframes etc). Each subframe can be ON for a PWM duration set by the individual PWM value. The PWM value setting of 2560 out of 4096 (12-bit) results in a ...
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PWM LED Drivers for Message Boards two external pnp transistors, such as FMMTL717, used as common-anode power switches (see Figure 5). Setting configuration bit enables multiplex Figure 5. MAX6975 Multiplexing Two Sets of Eight RGB Pixels ...
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Table 3. MAX6974/MAX6975 Timing Comparison MUX PART OPERATION BIT 0 Nonmultiplex MAX6974 1 Multiplex 0 Nonmultiplex MAX6975 1 Multiplex GLB4 MUX PART OPERATION BIT BIT X 0 Nonmultiplex MAX6974 X 1 Multiplex 0 Nonmultiplex 0 1 Multiplex MAX6975 0 Nonmultiplex ...
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PWM LED Drivers for Message Boards Each command is uniquely identified by two bits, C1 and C0, embedded in the serial-interface protocol structure. The commands Load CALDAC, Load Global- Intensity PDM, and Load Configuration each require 24 bits of ...
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The global-intensity data is received in an intermediate register and is applied to the outputs at subframe 0 and PWM clock 0. The MAX6974/MAX6975 have one byte of configuration data with 5 active bit settings as shown in Table 6. ...
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PWM LED Drivers for Message Boards The serial interface uses the continuously running clock, CLKI, to synchronously transfer and latch data (33MHz max). The MAX6974/MAX6975 sample inputs DIN and LOADI on the rising edge of CLKI and update outputs ...
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When LOADI is low, the MAX6974/MAX6975 continuously monitor DIN for reception of the SYNC pattern (see the Header Segment ...
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PWM LED Drivers for Message Boards The bit length of the data segment received by the MAX6974/MAX6975 is dependent on the command specified in the header. The load CALDAC command has three unique data bytes, while load global-intensity PDM ...
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HOST MAX6974/MAX6975 CLK0 CLKI CLKO D0 DIN DOUT LOAD0 LOADI LOADO LOADI DIN CLKI Figure 8. Example Showing Three-Device Cascade Connection Scheme with the Interconnecting Nodes Labeled for Clarity DATA: CALDAC DATA 1 B CALDAC G CALDAC 1 LOADI 0 ...
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PWM LED Drivers for Message Boards When the MAX6974/MAX6975 send individual-intensity PWM data, the data segment bit length is large due to the 12-bit or 14-bit PWM data for each of the 24 outputs (see Figure 11). The various ...
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Use the same length interface signal paths, whether differential or CMOS, to ensure a uniform propagation delay for each signal. Power-Supply Considerations The MAX6974/MAX6975 operate with a power-supply voltage of 3.0V to 3.6V. Bypass the V to GND with a ...
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PWM LED Drivers for Message Boards (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) 22 ______________________________________________________________________________________ Package Information ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 23 © 2007 Maxim Integrated Products ...