ADM1022

a FEATURES External Temperature Measurement with Remote Diode (Two Channels) On-Chip Temperature Sensor Interrupt and Over-Temperature Outputs Fault Tolerant Fan Control Brownout Detection LDCM Support System Management Bus (SMBus) Standby Mode to Minimize Power Consumption Limit Comparison of all Monitored Values APPLICATIONS Network Servers and Personal Computers Microprocessor-Based Office Equipment Test Equipment and Measuring Instruments Low-Cost PC Temperature Monitor and Fan Control ASIC ADM1022 GENERAL DESCRIPTION The ADM1022 is a low cost temperature monitor and fan controller for microprocessor-based systems. The temperature of one or two remote sensor diodes may be measured, allowing monitoring of processor temperature in single- or dual-processor systems. Measured values can be read out via a serial System Management Bus, and values for limit comparisons can be programmed in over the same serial bus. The ADM1022 also contains a DAC for fan speed control. Automatic hardware temperature trip points are provided and the fan will be driven to full speed if they are exceeded. Finally, the chip has two supply voltage monitors for brownout detection. The ADM1022’s 3.0 V to 5.5 V supply voltage range, low supply current, and SMBus interface make it ideal for a wide range of applications. These include hardware monitoring and protection applications in personal computers, electronic test equipment and office electronics. FUNCTIONAL BLOCK DIAGRAM VCC VMON ADD/NTEST_OUT RS...