MAX7324 Maxim, MAX7324 Datasheet
MAX7324
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MAX7324 Summary of contents
Page 1
... The interrupt is latched, allowing detection of transient changes. Any combina- tion of inputs can be selected using the interrupt mask to assert the INT output. When the MAX7324 is subse- quently accessed through the serial interface, any pending interrupt is cleared. The push-pull outputs are rated to sink 20mA and are capable of driving LEDs ...
Page 2
... Total GND Current ...........................................................100mA 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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I C Port Expander with Eight Push-Pull Outputs PORT AND INTERRUPT INT TIMING CHARACTERISTICS (V+ = +1.71V to +5.5V -40°C to +125°C, unless otherwise noted. Typical values are +3.3V PARAMETER SYMBOL Port-Output ...
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I C Port Expander with Eight Push-Pull Outputs and Eight Inputs (T = +25°C, unless otherwise noted.) A STANDBY CURRENT vs. TEMPERATURE 2.0 1.8 1.6 1.4 1.2 1 +3. +2.5V 0.8 0.6 0 ...
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... MAX7325 _______________________________________________________________________________________ The MAX7324 is set to two (see Tables 2 and 3) using address select inputs AD0 and AD2, and is accessed over 400kHz. The eight outputs and eight inputs have different slave addresses. The eight push-pull outputs have the 101xxxx addresses and the eight inputs have the adresses with 110xxxx ...
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... Yes — 12 Offers maximum versatility for automatic input monitoring. An interrupt mask selects which inputs cause an interrupt on transitions, and transition flags identify which inputs have changed (even if only for a transient) since the ports were last read. ...
Page 7
... Pullups are enabled on the input ports in groups of four (see Table 2). The MAX7324 slave address is determined on each I transmission, regardless of whether the transmission is actually addressing the MAX7324. The MAX7324 distin- guishes whether address inputs AD0 and AD2 are con- ...
Page 8
... Also, if SDA and SCL are terminated with pullup resistors to a different supply voltage than the MAX7324’s supply voltage, and if that pullup supply rises later than the MAX7324’s supply, then SDA or SCL may appear at power- connected to GND. In such applications, use the four address combina- ...
Page 9
... Enable interrupts for high-priori- ty inputs using the interrupt mask. The interrupt allows the system to respond quickly to changes on these inputs. Poll the MAX7324 periodically to monitor less- important inputs. The transition flags indicate whether a permanent or transient change has occurred on any input since the MAX7324 was last accessed. ...
Page 10
... The master initiates all data transfers to and from the MAX7324 and generates the SCL clock that synchronizes the data transfer (Figure 1). SDA operates as both an input and an open-drain out- put. A pullup resistor, typically 4.7kΩ ...
Page 11
... A single-byte read from the output ports of the MAX7324 returns the status of the eight output ports, read back as inputs. A 2-byte read from the input ports of the MAX7324 returns the status of the eight ports (as for a single-byte read), followed by the transition flags. The internal tran- ...
Page 12
... Figure 6. Reading Input Ports of the MAX7324 (1 Data Byte) 12 ______________________________________________________________________________________ 2 C STOP bit. A read from the input ports of the MAX7324 starts with the master transmitting the input ports’ slave address with the R/W bit set to high. The MAX7324 acknowl- edges the slave address and samples the ports during 2 C the acknowledge bit ...
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... FROM MAX7324 S MAX7324 SLAVE ADDRESS SCL PORTS t IV INT OUTPUT Figure 7. Reading Input Ports of the MAX7324 (2 Data Bytes) ACKNOWLEDGE FROM MAX7324 MAX7324 SLAVE ADDRESS S SCL Figure 8. Reading Output Ports of the MAX7324 ______________________________________________________________________________________ one or more bytes from the output ports of the MAX7324, and then issues a STOP condition (Figure 8). ...
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... C Port Expander with Eight Push-Pull Outputs and Eight Inputs Writing to the MAX7324 A write to the input ports of the MAX7324 starts with the master transmitting the group’s slave address with the R/W bit set low. The MAX7324 acknowledges the slave address and samples the ports during the acknowl- edge bit ...
Page 15
... higher supply to ensure a high logic voltage greater than 0.7 x V+. Port Output Signal Level Translation RST, SCL, SDA, AD0, and AD2 remain high impedance with up to +6V asserted on them when the MAX7324 is powered down (V+ = 0). The MAX7324 can therefore be used in hot-swap applications. V+ ...
Page 16
... Any combi- nation of outputs can be used as part of a load-sharing design because any combination of ports can be set or cleared at the same time by writing to the MAX7324. Do not exceed a total sink current of 100mA for the device. Protect the MAX7324 from the negative voltage tran- ...
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... and Eight Inputs Typical Application Circuit 3.3V V+ SCL SDA O15 RST O14 INT 013 012 MAX7324 O11 OUTPUT O10 OUTPUT 09 OUTPUT 08 OUTPUT AD0 I1 AD2 I0 GND Chip Information INPUT INPUT INPUT INPUT INPUT ...
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... I C Port Expander with Eight Push-Pull Outputs and Eight Inputs (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.) 18 ______________________________________________________________________________________ Package Information PACKAGE OUTLINE, 12, 16, 20, 24, 28L THIN QFN, 4x4x0.8mm ...
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... I C Port Expander with Eight Push-Pull Outputs (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.) ______________________________________________________________________________________ and Eight Inputs Package Information (continued) PACKAGE OUTLINE, 12, 16, 20, 24, 28L THIN QFN, 4x4x0.8mm ...
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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. ...