19-3057; Rev 0; 10/03 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection The MAX7312 is available in 24-pin SO, SSOP, TSSOP, and thin QFN packages and is specified over the -40°C to +125°C automotive temperature range. For applications requiring I/Os with integrated 100kΩ pullup resistors, refer to the MAX7311 data sheet. Applications Servers/Blades RAID Systems Medical Equipment Instrumentation and Test Measurement Networking Features ♦ 400kbps I2C-Compatible Serial Interface ♦ 2V to 5.5V Operation ♦ 5V Overvoltage Tolerant I/Os ♦ Supports Hot Insertion ♦ 16 I/O Pins that Default to Inputs on Power-Up ♦ Open-Drain Interrupt Output (INT) ♦ Bus Timeout for Lock-Up-Free Operation ♦ Noise Filter on SCL/SDA Inputs ♦ 64 User-Selectable Slave ID Addresses ♦ Low Standby Current (2.9µA typ) ♦ Polarity Inversion ♦ 4mm ✕ 4mm, 0.8mm Thin QFN Package ♦ -40°C to +125°C Operation Ordering Information PART TEMP RANGE PIN-PACKAGE MAX7312AWG -40°C to +125°C 24 Wide SO MAX7312AAG -40°C to +125°C 24 SSOP MAX7312ATG -40°C to +125°C 24 Thin QFN (4mm x 4mm) MAX7312AUG -40°C to +125°C 24 TSSOP SMBus is a trademark of Intel Corp. I2C Purchase of I2C components of Maxim Integrated Products, Inc., or one of its Sublicense Associate Companies conveys a license under the Philips I2C Patent Rights to use these components in an I2C system provided that the system conforms to the I2C Standard Specifications as defined by Philips. Pin Configurations TOP VIEW INT 1 24 V+ AD1 2 23 SDA AD2 3 I/O2 6 I/O3 7 I/O0 1 18 AD0 I/O1 2 17 I/O15 I/O2 3 I/O3 4 I/O4 5 I/O5 6 22 SCL I/O0 4 I/O1 5 AD2 AD1 INT V+ SDA SCL 24 23 22 21 20 19 16 I/O14 21 AD0 MAX7312 MAX7312 15 I/O13 20 I/O15 14 I/O12 19 I/O14 13 I/O11 18 I/O13 I/O4 8 17 I/O12 I/O5 9 16 I/O11 I/O6 10 15 I/O10 I/O7 11 14 I/O9 GND 12 13 I/O8 7 8 9 10 11 12 I/O6 I/O7 GND I/O8 I/O9 I/O10 THIN QFN TSSOP/SSOP/SO ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX7312 General Description The MAX7312 2-wire-interfaced expander provides 16-bit parallel input/output (I/O) port expansion in SMBus™ and I2C™ applications. The MAX7312 consists of input port registers, output port registers, polarity inversion registers, configuration registers, a bus timeout register, and an I2C-compatible serial interface logic, compatible with SMBus. The system master can invert the MAX7312 input data by writing to the active-high polarity inversion register. The system master can enable or disable bus timeout by writing to the bus timeout register. Any of the 16 I/O ports can be configured as an input or an output. A power-on reset (POR) initializes the 16 I/Os as inputs. Three address select pins configure the part to one of 64 slave ID addresses. The MAX7312 supports hot insertion. All port pins, the INT output, SDA, SCL, and the slave address inputs AD0-2 remain high impedance in power-down (Vt = 0V) up to 6V. MAX7312 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection ABSOLUTE MAXIMUM RATINGS V+ to GND ................................................................-0.3V to +6V I/O0–I/O15 as Inputs ....................................(GND - 0.3V) to +6V SCL, SDA, AD0, AD1, AD2, INT...................(GND - 0.3V) to +6V Maximum V+ Current ......................................................+250mA Maximum GND Current ...................................................-250mA DC Input Current on I/O0–I/O15 .......................................±20mA DC Output Current on I/O0–I/O15 ....................................±80mA Continuous Power Dissipation (TA = +70°C) 24-Pin Wide SO (derate 11.8mW/°C above +70°C) ....941mW 24-Pin SSOP (derate 8.0mW/°C above +70°C) ...........640mW 24-Pin TSSOP (derate 12.2mW/°C above +70°C) .......975mW 24-Pin Thin QFN (derate 20.8mW/°C above +70°C) .1668mW Operating Temperature Range .........................-40°C to +125°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C 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. DC ELECTRICAL CHARACTERISTICS (V+ = 2V to 5.5V, TA = -40°C to +125°C, unless otherwise noted. Typical values are at V+ = 3.3V, TA = +25°C.) (Note 1) PARAMETER Supply Voltage Supply Current Standby Current Power-On Reset Voltage SYMBOL V CONDITIONS MIN + I+ ISTBY TYP 2 All I/Os unloaded, fSCL = 400kHz All I/Os unloaded, fSCL = 0 MAX UNITS 5.5 V V+ = 2V 23 35 V+ = 3.3V 43 60 120 + µA V = 5.5V 80 V+ = 2V 2.3 11 V+ = 3.3V 2.9 12 V+ = 5.5V 3.8 15.5 1.4 1.7 V 0.3 x V+ V 0.4 V +1 µA VPOR µA SCL, SDA Input Voltage Low VIL Input Voltage High VIH Low-Level Output Voltage VOL Leakage Current 0.7 x V + V ISINK = 6mA IL -1 Input Capacitance 10 pF I/O_ Input Voltage Low VIL Input Voltage High VIH Input Leakage Current Low-Level Output Current ISINK ISOURCE V +1 µA 1.8 V TA = -40°C to +85°C -1 V+ = 2V, VOL = 0.5V 8.5 17 17 32 + V = 3.3V, VOL = 0.5V V+ = 5V, VOL = 0.5V High Output Current 0.8 V+ = 3.3V, VOH = 2.4V mA 43 29 V+ = 5V, VOH = 4.5V 41 mA 31 AD0, AD1, AD2 Input Voltage Low VIL Input Voltage High VIH 2 0.3 x V+ 0.7 x V+ _______________________________________________________________________________________ V V 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection (V+ = 2V to 5.5V, TA = -40°C to +125°C, unless otherwise noted. Typical values are at V+ = 3.3V, TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS Leakage Current MIN TYP -1 Input Capacitance MAX UNITS +1 µA 4 pF INT Low-Level Output Current IOL VOL = 0.4V 6 mA AC ELECTRICAL CHARACTERISTICS (V+ = 2V to 5.5V, TA = -40°C to +125°C, unless otherwise noted.) (Note 1) PARAMETER SCL Clock Frequency Bus Timeout SYMBOL fSCL CONDITIONS MIN TYP (Note 2) tTIMEOUT 29 MAX UNITS 400 kHz 61 ms Bus Free Time Between STOP and START Conditions tBUF Figure 2 1.3 µs Hold Time (Repeated) START Condition tHD,STA Figure 2 0.6 µs Repeated START Condition Setup Time tSU,STA Figure 2 0.6 µs STOP Condition Setup Time tSU,STO Figure 2 0.6 Data Hold Time tHD,DAT Figure 2 (Note 3) Data Setup Time tSU,DAT Figure 2 100 ns SCL Low Period tLOW Figure 2 1.3 µs SCL High Period tHIGH Figure 2 0.7 µs SDA Fall Time tF Figure 2 (Notes 4, 5) Pulse Width of Spike Suppressed tSP (Note 6) tPV Figure 7 µs 0.9 V+ < 3.3V 500 V+ ≥ 3.3V 250 50 µs ns ns PORT TIMING Output Data Valid 3 µs Input Data Setup Time 27 µs Input Data Hold Time 0 µs INTERRUPT TIMING Interrupt Valid tIV Figure 9 30.5 µs Interrupt Reset tIR Figure 9 2 µs Note 1: All parameters are 100% production tested at TA = +25°C. Specifications over temperature are guaranteed by design. Note 2: Minimum SCL clock frequency is limited by the MAX7312 bus timeout feature, which resets the serial bus interface if either SDA or SCL is held low for a minimum of 25ms. Disable bus timeout feature for DC operation. Note 3: A master device must internally provide a hold time of at least 300ns for the SDA signal (referred to the VIL of the SCL signal) in order to bridge the undefined region SCL’s falling edge. Note 4: CB = total capacitance of one bus line in pF. Note 5: The maximum tF for the SDA and SCL bus lines is specified at 300ns. The maximum fall time for the SDA output stage tF is specified at 250ns. This allows series protection resistors to be connected between the SDA and SCL pins and the SDA/SCL bus lines without exceeding the maximum specified tF. Note 6: Input filters on the SDA and SCL inputs suppress noise spikes less than 50ns. _______________________________________________________________________________________ 3 MAX7312 DC ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (TA = +25°C, unless otherwise noted.) 60 + 50 V = 3.3V 40 30 V = 2V 6 5 V+ = 3.3V 4 3 0 0 25 50 75 100 125 10 -25 0 25 50 75 100 2.0 125 2.5 3.0 3.5 4.0 4.5 5.0 I/O SINK CURRENT vs. OUTPUT LOW VOLTAGE I/O SINK CURRENT vs. OUTPUT LOW VOLTAGE 40 12 10 8 6 ISINK (mA) TA = +25°C TA = +125°C V+ = 3.3V 45 TA = -40°C 35 30 30 TA = +25°C 20 TA = +125°C 15 0.2 0.3 0.4 0.5 25 20 10 10 5 5 0.6 TA = +25°C TA = +125°C 15 0 0 0.1 TA = -40°C 40 35 25 V+ = 5V 45 ISINK (mA) 16 14 50 MAX7312 toc05 50 0 0.1 0.2 0.3 0.4 0.5 0 0.6 0.1 0.2 0.3 0.4 VOL (V) VOL (V) I/O OUTPUT LOW VOLTAGE vs. TEMPERATURE I/O SOURCE CURRENT vs. OUTPUT HIGH VOLTAGE I/O SOURCE CURRENT vs. OUTPUT HIGH VOLTAGE V+ = 5V, ISINK = 10mA V+ = 2V TA = -40°C 20 300 50 MAX7312 toc08 MAX7312 toc07 350 25 150 ISOURCE (mA) ISOURCE (mA) V+ = 2V, ISINK = 10mA 200 15 10 TA = +125°C 100 V+ = 2V, I SINK = 1mA V+ = 5V, ISINK = 1mA 25 25 20 TA = +125°C 10 5 0 0 TA = +25°C 30 15 5 0 -25 TA = -40°C 35 TA = +25°C 250 V+ = 3.3V 45 40 0.5 MAX7312 toc09 VOL (V) 400 5.5 MAX7312 toc06 I/O SINK CURRENT vs. OUTPUT LOW VOLTAGE 4 2 0 50 75 TEMPERATURE (°C) 4 30 SUPPLY VOLTAGE (V) 18 -50 40 TEMPERATURE (°C) TA = -40°C 50 50 TEMPERATURE (°C) V+ = 2V 0 60 0 -50 MAX7312 toc04 24 22 20 -25 70 20 0 -50 MAX7312 toc03 80 V+ = 2V 1 10 ISINK (mA) V+ = 5V 2 + 20 7 fSCL = 400kHz ALL I/Os UNLOADED 90 SUPPLY CURRENT (µA) + V = 5V 70 SUPPLY CURRENT (µA) SUPPLY CURRENT (µA) 80 SCL = V+ ALL I/Os UNLOADED 8 100 MAX7312 toc02 fSCL = 400kHz ALL I/Os UNLOADED 90 9 MAX7312 toc01 100 SUPPLY CURRENT vs. SUPPLY VOLTAGE STANDBY SUPPLY CURRENT vs. TEMPERATURE SUPPLY CURRENT vs. TEMPERATURE VOL (mV) MAX7312 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection 100 125 0 0 0.1 0.2 0.3 0.4 V+ - V OH (V) 0.5 0.6 0.7 0 0.1 0.2 0.3 0.4 V+ - VOH (V) _______________________________________________________________________________________ 0.5 0.6 0.7 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection I/O SOURCE CURRENT vs. OUTPUT HIGH VOLTAGE I/O HIGH VOLTAGE vs. TEMPERATURE TA = -40°C 40 MAX7312 toc11 V+ = 5V 45 500 MAX7312 toc10 50 400 V+ = 2V, ISOURCE = 10mA V+ - VOH (V) ISOURCE (mA) 35 TA = +25°C 30 25 20 300 200 TA = +125°C 15 10 100 5 V+ = 5V, ISOURCE = 10mA 0 0 0 0.1 0.2 0.3 0.4 0.5 0.6 -50 -25 V+ - VOH (V) 0 25 50 75 100 125 TEMPERATURE (°C) Pin Description PIN TSSOP/ SSOP/SO THIN QFN NAME 1 22 INT Interrupt Output (Open Drain) 2 23 AD1 Address Input 1 3 24 AD2 4–11 1–8 I/O0–I/O7 12 9 13–20 10–17 GND 21 18 22 23 24 FUNCTION Address Input 2 Input/Output Port 1 Supply Ground I/O8–I/O15 Input/Output Port 2 AD0 Address Input 0 19 SCL Serial Clock Line 20 SDA 21 V+ Serial Data Line Supply Voltage. Bypass with a 0.047µF capacitor to GND. _______________________________________________________________________________________ 5 MAX7312 Typical Operating Characteristics (continued) (TA = +25°C, unless otherwise noted.) MAX7312 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection AD0 INPUT/OUTPUT PORT 1 I/O0 I/O1 I/O2 I/O3 I/O4 I/O5 I/O6 I/O7 INPUT/OUTPUT PORT 2 I/O8 I/O9 I/O10 I/O11 I/O12 I/O13 I/O14 I/O15 8 BIT AD1 WRITE PULSE AD2 READ PULSE SCL SMBus CONTROL INPUT FILTER SDA 8 BIT N WRITE PULSE READ PULSE V+ INT POWER-ON RESET MAX7312 GND Figure 1. MAX7312 Block Diagram SDA tBUF tSU, STA tSU, DAT tHD, STA tLOW tSU, STO tHD, DAT SCL tHIGH tHD, STA tR tF REPEATED START CONDITION START CONDITION STOP CONDITION START CONDITION Figure 2. 2-Wire Serial Interface Timing Diagram Detailed Description Serial Interface The MAX7312 general-purpose input/output (GPIO) peripheral provides up to 16 I/O ports, controlled through an I 2 C-compatible serial interface. The MAX7312 consists of input port registers, output port registers, polarity inversion registers, configuration registers, and a bus-timeout register. Upon power-on, all I/O lines are set as inputs. Three slave ID address select pins, AD0, AD1, and AD2, choose one of 64 slave ID addresses, including the eight addresses supported by the Phillips PCA9555. Table 1 is the register address table. Tables 2–6 show detailed register information. The MAX7312 operates as a slave that sends and receives data through a 2-wire interface. The interface uses a serial data line (SDA) and a serial clock line (SCL) to achieve bidirectional communication between master(s) and slave(s). A master, typically a microcontroller, initiates all data transfers to and from the MAX7312, and generates the SCL clock that synchronizes the data transfer (Figure 2). 6 Serial Addressing _______________________________________________________________________________________ 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection MAX7312 SDA S P START CONDITION STOP CONDITION SCL Figure 3. START and STOP Conditions SDA SCL DATA LINE STABLE; DATA VALID CHANGE OF DATA ALLOWED Figure 4. Bit Transfer START CONDITION CLOCK PULSE FOR ACKNOWLEDGMENT SCL 1 2 8 9 SDA BY TRANSMITTER S SDA BY RECEIVER Figure 5. Acknowledge Each transmission consists of a START condition sent by a master, followed by the MAX7312 7-bit slave address plus R/W bit, a register address byte, 1 or more data bytes, and finally a STOP condition (Figure 3). Bit Transfer One data bit is transferred during each clock pulse. The data on SDA must remain stable while SCL is high (Figure 4). START and STOP Conditions Acknowledge Both SCL and SDA remain high when the interface is not busy. A master signals the beginning of a transmission with a START (S) condition by transitioning SDA from high to low while SCL is high. When the master has finished communicating with the slave, it issues a STOP (P) condition by transitioning SDA from low to high while SCL is high. The bus is then free for another transmission (Figure 3). The acknowledge bit is a clocked 9th bit, which the recipient uses as a handshake receipt of each byte of data (Figure 5). Thus, each byte transferred effectively requires 9 bits. The master generates the 9th clock pulse, and the recipient pulls down SDA during the acknowledge clock pulse, such that the SDA line is stable low during the high period of the clock pulse. When the master is transmitting to the MAX7312, the _______________________________________________________________________________________ 7 MAX7312 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection Slave address pins AD2, AD1, and AD0 choose 1 of 64 slave ID addresses (Table 7). MAX7312 generates the acknowledge bit since the MAX7312 is the recipient. When the MAX7312 is transmitting to the master, the master generates the acknowledge bit. Data Bus Transaction The command byte is the first byte to follow the 8-bit device slave address during a write transmission (Table 1, Figure 7). The command byte is used to determine which of the following registers are written or read. Slave Address The MAX7312 has a 7-bit-long slave address (Figure 6). The 8th bit following the 7-bit slave address is the R/W bit. Set this bit low for a write command and high for a read command. Writing to Port Registers Transmit data to the MAX7312 by sending the device slave address and setting the LSB to a logic zero. The command byte is sent after the address and determines which registers receive the data following the command byte (Figure 7). PROGRAMMABLE SDA A6 A5 A4 A3 A2 A1 A0 MSB R/W ACK LSB SDA Figure 6. Slave Address Table 1. Command Byte Register COMMAND BYTE ADDRESS (HEX) FUNCTION POWER-UP DEFAULT PROTOCOL 0x00 Input port 1 Read byte XXXX XXXX 0x01 Input port 2 Read byte XXXX XXXX 0x02 Output port 1 Read/write byte 1111 1111 0x03 Output port 2 Read/write byte 1111 1111 0x04 Port 1 polarity inversion Read/write byte 0000 0000 0x05 Port 2 polarity inversion Read/write byte 0000 0000 0x06 Port 1 configuration Read/write byte 1111 1111 0x07 Port 2 configuration Read/write byte 1111 1111 0x08 Timeout register Read/write byte 0000 0001 0xFF Factory reserved. (Do not write to this register.) SCL 1 2 3 4 5 6 7 8 S SLAVE ADDRESS R/W START CONDITION — 9 COMMAND BYTE SDA — A 0 0 ACKNOWLEDGE FROM SLAVE 0 0 0 0 PORT 1 DATA 1 0 A 7 6 ACKNOWLEDGE FROM SLAVE 5 4 3 PORT 2 DATA 2 1 0 A 7 6 ACKNOWLEDGE FROM SLAVE 5 4 3 2 1 0 A ACKNOWLEDGE FROM SLAVE WRITE TO PORT DATA OUT PORT 1 tPV READ FROM PORT 2 tPV Figure 7. Writes to Output Registers Through Write Byte Protocol 8 _______________________________________________________________________________________ 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection Reading Port Registers To read the device data, the bus master must first send the MAX7312 address with the R/W bit set to zero, followed by the command byte, which determines which register is accessed. After a restart, the bus master must then send the MAX7312 address with the R/W bit set to 1. Data from the register defined by the command byte is then sent from the MAX7312 to the master (Figures 8, 9). ACKNOWLEDGE FROM SLAVE SLAVE ADDRESS S COMMAND BYTE 0 A SLAVE ADDRESS A S R/W DATA FROM LOWER OR UPPER BYTE OF REGISTER MSB 1 A DATA LSB DATA FROM LOWER OR UPPER BYTE OF REGISTER MSB A DATA LSB PORT 2 DATA 0 NA P ACKNOWLEDGE FROM SLAVE R/W ACKNOWLEDGE FROM SLAVE MASTER TRANSMITTER BECOMES MASTER RECEIVER AND SLAVE RECEIVER BECOMES SLAVE TRANSMITTER TRANSFER OF DATA CAN BE STOPPED AT ANY TIME BY A STOP CONDITION. Figure 8. Read from Register SCL 1 S 2 3 4 5 6 SLAVE ADDRESS 7 8 1 9 A 7 PORT 1 DATA 0 A 7 PORT 2 DATA 0 A 7 PORT 1 DATA 0 A 7 1 P R/W ACKNOWLEDGE FROM SLAVE ACKNOWLEDGE FROM MASTER ACKNOWLEDGE FROM MASTER ACKNOWLEDGE FROM MASTER NONACKNOWLEDGE FROM MASTER READ FROM PORT 1 DATA INTO PORT 1 READ FROM PORT 2 DATA INTO PORT 2 INT tIV tIR TRANSFER OF DATA CAN BE STOPPED ANYTIME BY A STOP CONDITION. WHEN THE STOP CONDITION OCCURS, DATA PRESENT AT THE LAST ACKNOWLEDGE PHASE IS VALID (OUTPUT MODE) AND COMMAND BYTE HAS PREVIOUSLY BEEN SET TO REGISTER 00. Figure 9. Read from Input Registers _______________________________________________________________________________________ 9 MAX7312 Eight of the MAX7312’s nine registers are configured to operate as four register pairs: input ports, output ports, polarity inversion ports, and configuration ports. After sending 1 byte of data to one register, the next byte is sent to the other register in the pair. For example, if the first byte of data is sent to output port 2, then the next byte of data is stored in output port 1. An unlimited number of data bytes can be sent in one write transmission. This allows each 8-bit register to be updated independently of the other registers. MAX7312 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection Input/Output Port Data is clocked into a register on the falling edge of the acknowledge clock pulse. After reading the first byte, additional bytes may be read and reflect the content in the other register in the pair. For example, if input port 1 is read, the next byte read is input port 2. An unlimited number of data bytes can be read in one read transmission, but the final byte received must not be acknowledged by the bus master. When an I/O is configured as an input, FETs Q1 and Q2 are off (Figure 10), creating a high-impedance input. All inputs are overvoltage protected to 5.5V, independent of supply voltage. When a port is configured as an output, either Q1 or Q2 is on, depending on the state of the output port register. When V+ powers up, an internal power-on reset sets all registers to their respective defaults (Table 1). Interrupt (INT) The open-drain interrupt output, INT, activates when one of the port pins changes states and only when the pin is configured as an input. The interrupt deactivates when the input returns to its previous state or the input register is read (Figure 9). A pin configured as an output does not cause an interrupt. Each 8-bit port register is read independently; therefore, an interrupt caused by port 1 is not cleared by a read of port 2’s register. Changing an I/O from an output to an input may cause a false interrupt to occur if the state of that I/O does not match the content of the input port register. Input Port Registers The input port registers (Table 2) are read-only ports. They reflect the incoming logic levels of the pins, regardless of whether the pin is defined as an input or an output by the respective configuration register. A read of the input port 1 register latches the current value of I/O0–I/O7. A read of the input port 2 register latches the current value of I/O8–I/O15. Writes to the input port registers are ignored. OUTPUT PORT REGISTER DATA DATA FROM SHIFT REGISTER WRITE CONFIGURATION PULSE CONFIGURATION REGISTER SET D Q VDD Q1 I/O PIN Q CLR DATA FROM SHIFT REGISTER WRITE PULSE SET D Q Q CLR OUTPUT PORT REGISTER Q2 VSS INPUT PORT REGISTER SET Q D INPUT PORT REGISTER DATA READ PULSE Q CLR TO INT POWER-ON RESET DATA FROM SHIFT REGISTER WRITE POLARITY PULSE SET D Q POLARITY REGISTER DATA Q CLR POLARITY INVERSION REGISTER Figure 10. Simplified Schematic of I/Os 10 ______________________________________________________________________________________ 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection MAX7312 Table 2. Registers 0x00, 0x01—Input Port Registers BIT I7 I6 I5 I4 I3 I2 I1 I0 I15 I14 I13 I12 I11 I10 I9 I8 Table 3. Registers 0x02, 0x03—Output Port Registers BIT Power-up default O7 O6 O5 O4 O3 O2 O1 O0 O15 O14 O13 O12 O11 O10 O9 O8 1 1 1 1 1 1 1 1 Table 4. Registers 0x04, 0x05—Polarity Inversion Registers BIT Power-up default I/O7 I/O6 I/O5 I/O4 I/O3 I/O2 I/O1 I/O0 I/O15 I/O14 I/O13 I/O12 I/O11 I/O10 I/O9 I/O8 0 0 0 0 0 0 0 0 Table 5. Registers 0x06, 0x07—Configuration Registers BIT Power-up default I/O7 I/O6 I/O5 I/O4 I/O3 I/O2 I/O1 I/O0 I/O15 I/O14 I/O13 I/O12 I/O11 I/O10 I/O9 I/O8 1 1 1 1 1 1 1 1 Table 6. Register 0x08—Timeout Register BIT 7 6 5 4 3 2 1 0 Power-up default 0 0 0 0 0 0 0 1 Output Port Registers The output port registers (Table 3) set the outgoing logic levels of the I/Os defined as outputs by the respective configuration register. Reads from the output port registers reflect the value that is in the flip-flop controlling the output selection, not the actual I/O value. Polarity Inversion Registers The polarity inversion registers (Table 4) enable polarity inversion of pins defined as inputs by the respective port configuration registers. Set the bit in the polarity inversion register to invert the corresponding port pin’s polarity. Clear the bit in the polarity inversion register to retain the corresponding port pin’s original polarity. Configuration Registers The configuration registers (Table 5) configure the directions of the I/O pins. Set the bit in the respective configuration register to enable the corresponding port as an input. Clear the bit in the configuration register to enable the corresponding port as an output. Bus Timeout Set register 0x08 LSB (bit 0) to enable the bus timeout function (Table 6) or clear it to disable the bus timeout function. Enabling the timeout feature resets the MAX7312 serial bus interface when SCL stops either high or low during a read or write. If either SCL or SDA is low for more than 29ms after the start of a valid serial transfer, the interface resets itself and sets up SDA as an input. The MAX7312 then waits for another START condition. Standby The MAX7312 goes into standby when the I2C bus is idle. Standby supply current is typically 2.9µA. Applications Information Hot Insertion The I/O ports I/O0–I/O15 interrupt output IRQ, and serial interfaces SDA, SCL, AD0-2 remain high impedance with up to 6V asserted on them when the MAX7312 is powered down (V+ = 0V). The MAX7312 can therefore be used in hot-swap applications. Power-Supply Consideration The MAX7312 operates from a supply voltage of 2V to 5.5V. Bypass the power supply to GND with a 0.047µF capacitor as close to the device as possible. ______________________________________________________________________________________ 11 MAX7312 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection Table 7. MAX7312 Address Map AD2 AD1 AD0 A6 A5 A4 A3 A2 A1 A0 ADDRESS (HEX) GND SCL GND 0 0 1 0 0 0 0 0x20 0x22 GND SCL V 0 0 1 0 0 0 1 GND SDA GND 0 0 1 0 0 1 0 0x24 GND SDA V+ 0 0 1 0 0 1 1 0x26 V+ SCL GND 0 0 1 0 1 0 0 0x28 V+ SCL V+ 0 0 1 0 1 0 1 0x2A V+ SDA GND 0 0 1 0 1 1 0 0x2C V + + SDA V 0 0 1 0 1 1 1 0x2E GND SCL SCL 0 0 1 1 0 0 0 0x30 GND SCL SDA 0 0 1 1 0 0 1 0x32 GND SDA SCL 0 0 1 1 0 1 0 0x34 GND SDA SDA 0 0 1 1 0 1 1 0x36 V+ SCL SCL 0 0 1 1 1 0 0 0x38 V+ SCL SDA 0 0 1 1 1 0 1 0x3A + SDA SCL 0 0 1 1 1 1 0 0x3C V+ SDA SDA 0 0 1 1 1 1 1 0x3E GND GND GND 0 1 0 0 0 0 0 0x40 GND GND V+ 0 1 0 0 0 0 1 0x42 GND 0 1 0 0 0 1 0 0x44 0x46 V + GND V GND V+ V+ 0 1 0 0 0 1 1 V+ GND GND 0 1 0 0 1 0 0 0x48 V+ GND V+ 0 1 0 0 1 0 1 0x4A V+ V+ GND 0 1 0 0 1 1 0 0x4C + + V V V + 0 1 0 0 1 1 1 0x4E GND GND SCL 0 1 0 1 0 0 0 0x50 GND GND SDA 0 1 0 1 0 0 1 0x52 GND V + SCL 0 1 0 1 0 1 0 0x54 GND V+ SDA 0 1 0 1 0 1 1 0x56 V+ GND SCL 0 1 0 1 1 0 0 0x58 V+ GND V + V+ 12 + SDA 0 1 0 1 1 0 1 0x5A + SCL 0 1 0 1 1 1 0 0x5C V+ SDA 0 1 0 1 1 1 1 0x5E V ______________________________________________________________________________________ 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection AD2 AD1 AD0 A6 A5 A4 A3 A2 A1 A0 ADDRESS (HEX) SCL SCL GND 1 0 1 0 0 0 0 0xA0 SCL SCL V+ 1 0 1 0 0 0 1 0xA2 SCL SDA GND 1 0 1 0 0 1 0 0xA4 SCL SDA V+ 1 0 1 0 0 1 1 0xA6 SDA SCL GND 1 0 1 0 1 0 0 0xA8 SDA SCL V+ 1 0 1 0 1 0 1 0xAA SDA SDA GND 1 0 1 0 1 1 0 0xAC SDA SDA V+ 1 0 1 0 1 1 1 0xAE SCL SCL SCL 1 0 1 1 0 0 0 0xB0 SCL SCL SDA 1 0 1 1 0 0 1 0xB2 SCL SDA SCL 1 0 1 1 0 1 0 0xB4 SCL SDA SDA 1 0 1 1 0 1 1 0xB6 SDA SCL SCL 1 0 1 1 1 0 0 0xB8 SDA SCL SDA 1 0 1 1 1 0 1 0xBA SDA SDA SCL 1 0 1 1 1 1 0 0xBC SDA SDA SDA 1 0 1 1 1 1 1 0xBE SCL GND GND 1 1 0 0 0 0 0 0xC0 SCL GND V+ 1 1 0 0 0 0 1 0xC2 SCL V+ GND 1 1 0 0 0 1 0 0xC4 + 0xC6 SCL V 1 1 0 0 0 1 1 SDA GND GND 1 1 0 0 1 0 0 0xC8 SDA GND V+ 1 1 0 0 1 0 1 0xCA SDA V+ GND 1 1 0 0 1 1 0 0xCC SDA V+ V+ 1 1 0 0 1 1 1 0xCE SCL GND SCL 1 1 0 1 0 0 0 0xD0 SCL GND SDA 1 1 0 1 0 0 1 0xD2 SCL V+ SCL 1 1 0 1 0 1 0 0xD4 SCL V+ SDA 1 1 0 1 0 1 1 0xD6 SDA GND SCL 1 1 0 1 1 0 0 0xD8 SDA GND SDA 1 1 0 1 1 0 1 0xDA SDA V+ SCL 1 1 0 1 1 1 0 0xDC SDA + SDA 1 1 0 1 1 1 1 0xDE V V + Chip Information TRANSISTOR COUNT: 12,994 PROCESS: BiCMOS ______________________________________________________________________________________ 13 MAX7312 Table 7. MAX7312 Address Map (continued) Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.) INCHES N E DIM A A1 B C e E H L H MAX MIN 0.093 0.104 0.004 0.012 0.014 0.019 0.009 0.013 0.050 0.291 0.299 0.394 0.419 0.050 0.016 SOICW.EPS MAX7312 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection MILLIMETERS MIN 2.35 0.10 0.35 0.23 MAX 2.65 0.30 0.49 0.32 1.27 7.40 7.60 10.00 10.65 0.40 1.27 VARIATIONS: 1 INCHES TOP VIEW DIM D D D D D D A B e FRONT VIEW MIN 0.398 0.447 0.496 0.598 0.697 MAX 0.413 0.463 0.512 0.614 0.713 MILLIMETERS MIN 10.10 11.35 12.60 15.20 17.70 MAX 10.50 11.75 13.00 15.60 18.10 N MS013 16 AA 18 AB 20 AC 24 AD 28 AE C 0∞-8∞ A1 L SIDE VIEW PROPRIETARY INFORMATION TITLE: PACKAGE OUTLINE, .300" SOIC APPROVAL DOCUMENT CONTROL NO. 21-0042 14 ______________________________________________________________________________________ REV. B 1 1 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection SSOP.EPS 2 1 INCHES E H MILLIMETERS DIM MIN MAX MIN MAX A 0.068 0.078 1.73 1.99 A1 0.002 0.008 0.05 0.21 B 0.010 0.015 0.25 0.38 C D 0.20 0.09 0.004 0.008 SEE VARIATIONS E 0.205 e 0.212 0.0256 BSC 5.20 MILLIMETERS INCHES D D D D D 5.38 MIN MAX MIN MAX 0.239 0.239 0.278 0.249 0.249 0.289 6.07 6.07 7.07 6.33 6.33 7.33 0.317 0.397 0.328 0.407 8.07 10.07 8.33 10.33 N 14L 16L 20L 24L 28L 0.65 BSC H 0.301 0.311 7.65 7.90 L 0.025 0∞ 0.037 8∞ 0.63 0∞ 0.95 8∞ N A C B e A1 L D NOTES: 1. D&E DO NOT INCLUDE MOLD FLASH. 2. MOLD FLASH OR PROTRUSIONS NOT TO EXCEED .15 MM (.006"). 3. CONTROLLING DIMENSION: MILLIMETERS. 4. MEETS JEDEC MO150. 5. LEADS TO BE COPLANAR WITHIN 0.10 MM. PROPRIETARY INFORMATION TITLE: PACKAGE OUTLINE, SSOP, 5.3 MM APPROVAL DOCUMENT CONTROL NO. 21-0056 REV. C 1 1 ______________________________________________________________________________________ 15 MAX7312 Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.) Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.) TSSOP4.40mm.EPS MAX7312 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection 16 ______________________________________________________________________________________ 2-Wire-Interfaced 16-Bit I/O Port Expander with Interrupt and Hot-Insertion Protection 24L QFN THIN.EPS PACKAGE OUTLINE 12,16,20,24L QFN THIN, 4x4x0.8 mm 21-0139 A PACKAGE OUTLINE 12,16,20,24L QFN THIN, 4x4x0.8 mm 21-0139 A 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 ____________________ 17 © 2003 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. MAX7312 Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.)