MAX7315 Maxim, MAX7315 Datasheet
MAX7315
Available stocks
Related parts for MAX7315
MAX7315 Summary of contents
Page 1
... All LEDs can be individually set off during either blink phase ignore the blink control. The blink period is controlled by a register. The MAX7315 supports hot insertion. All port pins, the INT output, SDA, SCL, and the slave address inputs ADO-2 remain high impedance in power-down (V+ = 0V) with asserted upon them ...
Page 2
... A 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 ...
Page 3
I/O Expander 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–P7, INT/O8 Output Low-Voltage SDA V OLSDA PWM Clock ...
Page 4
I/O Expander 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 Setup Time Input Data Hold ...
Page 5
... 0 2.7V 0 125 -40 -25 - TEMPERATURE (°C) SCOPE SHOT OF 2 OUTPUT PORTS MAX7315 toc08 MASTER INTENSITY SET TO 14/15 OUTPUT 1, 2V/div OUTPUT 1 INDIVIDUAL INTENSITY SET TO 1/16 OUTPUT 2, 2V/div OUTPUT 2 INDIVIDUAL INTENSITY SET TO 14/15 2ms/div PWM CLOCK FREQUENCY vs. TEMPERATURE 1.050 1.025 V+ = 3.6V 1.000 0.975 V+ = 2.7V ...
Page 6
... supply voltage. The MAX7315 is rated for a ground cur- rent of 190mA, allowing all nine outputs to sink 20mA at the same time. Figure 1 shows the output structure of the MAX7315. The ports default to inputs on power-up. Port Inputs and Transition Detection An input ports register reflects the incoming logic levels of the port pins, regardless of whether the pin is defined as an input or an output ...
Page 7
... MAX7315 and generates the SCL clock that synchronizes the data transfer (Figure 2). The MAX7315 SDA line operates as both an input and an open-drain output. A pullup resistor, typically 4.7kΩ, is required on SDA. The MAX7315 SCL line operates ...
Page 8
... AD0, AD1, and AD2. These pins can be connected to GND, V+, SDA, or SCL. The MAX7315 has 64 possible slave addresses (Table 1) and, there- fore, a maximum of 64 MAX7315 devices can be con- trolled independently from the same interface. CLOCK PULSE A write to the MAX7315 comprises the transmission of the MAX7315’ ...
Page 9
... I/O Expander with LED Intensity Control, Interrupt, and Hot-Insertion Protection 2 Table 1. MAX7315 I C Slave Address Map PIN AD2 PIN AD1 PIN AD0 GND SCL GND GND SCL V+ GND SDA GND GND SDA V+ V+ SCL GND V+ SCL V+ V+ SDA GND V+ SDA V+ GND ...
Page 10
... I/O Expander with LED Intensity Control, Interrupt, and Hot-Insertion Protection 2 Table 1. MAX7315 I C Slave Address Map (continued) PIN AD2 PIN AD1 PIN AD0 SCL SCL GND SCL SCL V+ SCL SDA GND SCL SDA V+ SDA SCL GND SDA SCL V+ SDA SDA GND ...
Page 11
... This is because it is possible for master 2 to take over the bus after master 1 has set up the MAX7315’s address pointer but before master 1 has read the data. If master 2 subsequently changes the MAX7315’s address pointer, then master 1’ ...
Page 12
... IV Figure 10. Read, Write, and Interrupt Timing Diagrams Command Address Autoincrementing The command address stored in the MAX7315 circu- lates around grouped register functions after each data byte is written or read (Table 2 device reset input is needed, consider the MAX7316. The MAX7316 includes a RST input, which ...
Page 13
... The interrupt status is available as the interrupt flag INT in the configuration register (Table 4). The input status of all ports is sampled immediately after power-up as part of the MAX7315’s internal initial- ______________________________________________________________________________________ ADDRESS CODE (HEX) 0x00 ...
Page 14
I/O Expander with LED Intensity Control, Interrupt, and Hot-Insertion Protection Table 3. Power-Up Configuration REGISTER FUNCTION POWER-UP CONDITION Blink phase 0 outputs P7–P0 High-impedance outputs Ports configuration P7–P0 Ports P7–P0 are inputs Blink phase 1 outputs P7–P0 High-impedance outputs ...
Page 15
I/O Expander with LED Intensity Control, Interrupt, and Hot-Insertion Protection Table 4. Configuration register (continued) REGISTER CONFIGURATION Disable data change interrupt—INT/O8 output is controlled by the O0 and O1 bits Enable data change interrupt—INT/O8 output is controlled by port ...
Page 16
... 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 MAX7315 to suit a particular application. The PWM control uses a 240-step PWM period, divided into 15 master intensity timeslots ...
Page 17
... PWM control must be selected (Table 10). Applications Information I/O ports PO-P7, interrupt output INT/08, and serial interface SDA, SCL, AD0-2 remain high impedance with asserted on them when the MAX7315 is pow- ered down (V+ = 0V). The MAX7315 can therefore be used in hot-swap applications. Table 8. Blink Phase 0 Register ...
Page 18
I/O Expander 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 ...
Page 19
I/O Expander with LED Intensity Control, Interrupt, and Hot-Insertion Protection MASTER INTENSITY TIMESLOT Figure 15. Individual (or Global) Set to 1/16 MASTER INTENSITY TIMESLOT Figure ...
Page 20
... LED Driving Load Currents Higher than 50mA The MAX7315 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 ...
Page 21
I/O Expander with LED Intensity Control, Interrupt, and Hot-Insertion Protection Table 13. Master, O8 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); ...
Page 22
I/O Expander 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 ...
Page 23
... AD0 AD1 2 15 SDA AD2 3 14 SCL MAX7315AEE INT/O8 MAX7315AUE GND QSOP/TSSOP Typical Application Circuit 5V 3. SDA MAX7315 P3 SCL P4 P5 INT/ AD0 AD1 AD2 GND INPUT 1 INPUT 2 OUTPUT1 OUTPUT2 23 ...
Page 24
... I/O Expander 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 ...
Page 25
... I/O Expander 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.) MARKING D/2 D 0.10 C PKG 8L 3x3 REF. MIN. NOM. MAX. MIN. ...
Page 26
... 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. ...