MAX7314 Maxim, MAX7314 Datasheet
MAX7314
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MAX7314 Summary of contents
Page 1
... BLINK register. The BLINK input can also be used as a logic control to turn the LEDs on and off general-purpose input. The MAX7314 supports hot insertion. All port pins, the INT output, SDA, SCL, RST, BLINK, and the slave address input ADO remain high impedance in power- down (V+ = 0V) with asserted upon them ...
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... Maximum GND Current ....................................................350mA Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability ...
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GPIO with LED Intensity Control, Interrupt, and Hot-Insertion Protection ELECTRICAL CHARACTERISTICS (continued) (Typical Operating Circuit 3.6V, T (Note 1) PARAMETER SYMBOL Output Low Voltage V P0–P15, INT/O16 Output Low-Voltage SDA V OLSDA PWM Clock Frequency ...
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GPIO with LED Intensity Control, Interrupt, and Hot-Insertion Protection TIMING CHARACTERISTICS (continued) (Typical Operating Circuit 3.6V, T (Note 1) PARAMETER Interrupt Valid Interrupt Reset Output Data Valid Input Data Set-Up Time Input Data Hold Time ...
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... PWM CLOCK FREQUENCY vs. TEMPERATURE 1.050 1.025 V+ = 3.6V 1.000 0.975 V+ = 2.7V 0.950 0.925 NORMALIZED 3.3V, T 0.900 95 110 125 -40 -25 - TEMPERATURE (°C) SINK CURRENT vs. V MAX7314 toc08 0.35 0.30 OUTPUT 2V/div 0. 2.7V 0. 3.3V 0.15 OUTPUT 2 0.10 2V/div 0.05 ONLY ONE OUTPUT LOADED SINK CURRENT (mA +25° ...
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... MAX7314’s supply voltage. The MAX7314 is rated for a ground current of 350mA, allowing all 17 outputs to sink 20mA at the same time. Figure 1 shows the output structure of the MAX7314. The ports default to inputs on power-up. Pin Description FUNCTION OUTPUT PORT ...
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... The MAX7314 includes an internal oscillator, nominally 32kHz, to generate PWM timing for LED intensity control. PWM intensity control can be enabled on an output-by- output basis, allowing the MAX7314 to provide any mix of PWM LED drives and glitch-free logic outputs (Table 10). PWM can be disabled entirely, in which case all out- put ports are static and the MAX7314 operating current is lowest because the internal oscillator is turned off ...
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... The MAX7314 has a 7-bit long slave address (Figure 6). The eighth bit following the 7-bit slave address is the R/W bit. The R/W bit is low for a write command, high for a read command. ...
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... MAX7314 slave address are always and 0. Slave address bits A6 and A2 are selected by the address input AD0. AD0 can be con- nected to GND, V+, SDA, or SCL. The MAX7314 has four possible slave addresses (Table 1), and therefore a maximum of four MAX7314 devices can be controlled independently from the same interface ...
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... This is because it is possible for master 2 to take over the bus after master 1 has set up the MAX7314’s address pointer but before master 1 has read the data. If master 2 subsequently changes the MAX7314’s address pointer, then master 1’ ...
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... Outputs intensity P13, P12 Outputs intensity P15, P14 The reset input RST is an active-low input. When taken low, RST clears any transaction to or from the MAX7314 on the serial interface and configures the internal regis- ters to the same state as a power-up reset (Table 3), which resets all ports as inputs ...
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... INT in the configuration register (Table 4). The input status of all ports is sampled immediately after power-up as part of the MAX7314’s internal initial- ization all the ports are pulled to valid logic levels at that time, an interrupt does not occur at power-up. ...
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GPIO with LED Intensity Control, Interrupt, and Hot-Insertion Protection Table 4. Configuration Register REGISTER CONFIGURATION Write device configuration Read back device configuration Disable blink Enable blink Flip blink register (see text) Disable global intensity control—intensity is set by registers ...
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GPIO with LED Intensity Control, Interrupt, and Hot-Insertion Protection Table 4. Configuration Register (continued) REGISTER CONFIGURATION Write device configuration Read back device configuration Read back BLINK input pin status— input is low Read back BLINK input pin status— input ...
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... When all outputs are to be used with the same PWM setting, the outputs can be controlled together instead using the global intensity control (Table 13). Table 10 shows how to set up the MAX7314 to suit a particular application. The PWM control uses a 240-step PWM period, divided into 15 master intensity timeslots ...
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GPIO with LED Intensity Control, Interrupt, and Hot-Insertion Protection Table 8. Blink Phase 0 Registers REGISTER Write outputs P7–P0 phase 0 Read back outputs P7–P0 phase 0 Write outputs P15–P8 phase 0 Read back outputs P15–P8 phase 0 Table ...
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GPIO with LED Intensity Control, Interrupt, and Hot-Insertion Protection Table 10. PWM Application Scenarios APPLICATION All outputs static without PWM A mix of static and PWM outputs, with PWM outputs using different PWM settings A mix of static and ...
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GPIO with LED Intensity Control, Interrupt, and Hot-Insertion Protection MASTER INTENSITY TIMESLOT Figure 16. Individual (or Global) Set to 1/16 MASTER INTENSITY TIMESLOT ...
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... I/O ports P0–P15, interrupt output INT/O16, RST input, BLINK input, and serial interface SDA, SCL, AD0 remain high impedance with asserted on them when the MAX7314 is powered down (V+ = 0V). The MAX7314 can therefore be used in hot-swap applications. Output Level Translation The open-drain output architecture allows the ports to level translate the outputs to higher or lower voltages than the MAX7314 supply ...
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GPIO with LED Intensity Control, Interrupt, and Hot-Insertion Protection Table 13. Master, O16 Intensity Register REGISTER MASTER AND GLOBAL INTENSITY Write master and global intensity Read back master and global intensity Master intensity duty cycle is 0/15 (off); internal ...
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GPIO with LED Intensity Control, Interrupt, and Hot-Insertion Protection Table 14. Output Intensity Registers REGISTER OUTPUTS P1, P0 INTENSITY Write output P1, P0 intensity Read back output P1, P0 intensity Output P1 intensity duty cycle is 1/16 Output P1 ...
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... Read back output P15, P14 intensity OUTPUT O16 INTENSITY Driving Load Currents Higher than 50mA The MAX7314 can be used to drive loads drawing more than 50mA, like relays and high-current white LEDs, by paralleling outputs. Use at least one output per 50mA of load current; for example 330mW relay draws 66mA and needs two paralleled outputs to drive it ...
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... GND TRANSISTOR COUNT: 25,991 PROCESS: BiCMOS 5V BAS16 Pin Configurations INT/O16 RST 2 23 SDA AD0 3 22 SCL BLINK MAX7314AEG P15 P14 P13 P12 P11 P10 GND 12 13 ...
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... GPIO with LED Intensity Control, Interrupt, and Hot-Insertion Protection (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.) 24 ______________________________________________________________________________________ Package Information ...
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... For the latest package outline information www.maxim-ic.com/packages.) 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. ...