ABCelectronique : portail d'information dans le domaine de l'électronique
 
 
Numéro de sérieMAX8211
CategoriePower Management => Supervisory Circuits => Voltage Detectors
DescriptionMicroprocessor Voltage Monitors With Programmable Voltage Detection
Maxim\'s MAX8211 and MAX8212 are CMOS micropower voltage detectors that warn microprocessors (µPs) of power failures. Each contains a comparator, a 1.5V bandgap reference, and an open-drain n-channel output driver. Two external resistors are used in conjunction with the internal reference to set the trip voltage to the desired level. A hysteresis output is also included, allowing the user to apply positive feedback for noise-free output switching
SociétéMaxim Integrated Products
DatasheetTélécharger MAX8211 datasheet
 
 
  • Description courte

  • Microprocessor Voltage Monitors with Programmable Voltage Detection MAX8211/MAX8212

    Maxim's MAX8211 and MAX8212 are CMOS micropower voltage detectors that warn microprocessors (µPs) of power failures. Each contains a comparator, a 1.5V bandgap reference, and an open-drain n-channel output driver. Two external resistors are used in conjunction with the internal reference to set the trip voltage to the desired level. A hysteresis output is also included, allowing the user to apply positive feedback for noise-free output switching. The MAX8211 provides a 7mA current-limited output sink whenever the voltage applied to the threshold pin is less than the 1.5V internal reference. In the MAX8212, a voltage greater than 1.5V at the threshold pin turns the output stage on (no current limit). The CMOS MAX8211/MAX8212 are plug-in replacements for the bipolar ICL8211/ICL8212 in applications where the maximum supply voltage is less than 16.5V. They offer several performance advantages, including reduced supply current, a more tightly controlled bandgap reference, and more available current from the hysteresis output.

    o µP Power-Fail Warning o Improved 2nd Source for ICL8211/ICL8212 o Low-Power CMOS Design 5µA Quiescent Current On-Board Hysteresis Output ±40mV Threshold Accuracy to 16.5V Supply-Voltage Range Define Output Current Limit (MAX8211)

    PART MAX8211ETY MAX8211MJA TEMP RANGE to +125°C PINPACKAGE 8 Plastic DIP SO 8 µMAX TO-99 8 Plastic DIP SO 8 CERDIP TO-99 8 CERDIP**

    µP Voltage Monitoring Undervoltage Detection Overvoltage Detection Battery-Backup Switching Power-Supply Fault Monitoring Low-Battery Detection

    Ordering Information continued on last page. *Contact factory for dice specifications. **Contact factory for availability and processing to MIL-STD-883.

    LOGIC-SUPPLY UNDERVOLTAGE DETECTOR (DETAILED CIRCUIT DIAGRAM--FIGURE 5)

    For pricing, delivery, and ordering information, please contact Maxim Direct 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com.

    Supply to +18V Output to -18V with respect to (V+ + 0.5V) Threshold Input Voltage...............................-0.5V to (V+ + 0.5V) Current into Any Terminal.................................................±50mA Continuous Power Dissipation (TA +70°C) 8-Pin Plastic DIP (derate 9.09mW/°C above 8-Pin SO (derate 5.88mW/°C above +70°C)..................471mW 8-Pin CERDIP (derate 8.00mW/°C above 8-Pin TO-99 (derate 6.67mW/°C above +70°C).............533mW Operating Temperature Ranges to +125°C Storage Temperature 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.

    (V+ = +25°C, unless otherwise noted.) PARAMETER Supply Current SYMBOL I+ CONDITIONS V+ 16.5V, GND VTH = +25°C Threshold Trip Voltage VTH TA = TMIN to TMAX Threshold Voltage Disparity between Output and Hysteresis Output Guaranteed Operating Supply Voltage Range Typical Operating Supply Voltage Range Threshold Voltage Temperature Coefficient Variation of Threshold Voltage with Supply Voltage Threshold Input Current IOUT = 4mA, IHYST TA = TMIN to TMAX VOUT = 16.5V, VTH TA = TMIN to TMAX, VOUT = 16.5V, VTH = 1.3V C/E temp. ranges VOUT = 5V, VTH = 1.0V Output Leakage Current ILOUT VOUT = 5V, VTH = 1.3V VOUT = 16.5V, VTH TA = TMIN to TMAX, VOUT = 16.5V, VTH 1.3V M temp. range VOUT = 5V, VTH = 0.9V VOUT = 5V, VTH TA = TMIN to TMAX = 16.5V, IOUT = 2V, IOUT = 16.5V, IOUT = 2.2V, IOUT MAX8211 MAX8212 UNITS MIN TYP MAX MIN TYP MAX 1.25 µA

    (V+ = +25°C, unless otherwise noted.) PARAMETER Output Saturation Voltage Maximum Available Output Current SYMBOL VOL IOH CONDITIONS IOUT = 2mA, VTH = 1.0V IOUT = 2mA, VTH 1.3V C temp. range, VOUT = 5V VTH = 1.0V (Note 1) VTH = 1.3V (Note TA = TMIN to TMAX, M temp. range, = 16.5V, VTH = 0.9V, VHYST = -16.5V with respect to V+ VHYS (MAX) VHYS (MAX) IHYST = 0.5mA, VTH = 1.3V, measured with respect to V+ VTH = 1.3V, VHYS MAX8211 MAX8212 UNITS MIN TYP MAX MIN TYP MAX V mA

    TA = TMIN to TMAX, C/E temp. ranges, = 16.5V, VTH = 1.0V, VHYST = -16.5V with respect to V+ ILHYS
    Hysteresis Saturation Voltage Maximum Available Hysteresis Current

    Note 1: The maximum output current of the MAX8211 is limited by design to 30mA under any operating condition. The output voltage may be sustained at any voltage +16.5V as long as the maximum power dissipation of the device is not exceeded. Note 2: The maximum output current of the MAX8212 is not defined, and systems using the MAX8212 must therefore ensure that the output current does not exceed 50mA and that the maximum power dissipation of the device is not exceeded.

    As shown in the block diagrams of Figures 1 and 2, the MAX8211 and MAX8212 each contain a 1.15V reference, a comparator, an open-drain n-channel output transistor, and an open-drain p-channel hysteresis output. The MAX8211 output n-channel turns on when the voltage applied to the THRESH pin is less than the internal reference (1.15V). The sink current is limited to 7mA (typical), allowing direct drive of an LED without a series resistor. The MAX8212 output turns on when the voltage applied to THRESH is greater than the internal reference. It is not current limited, and will typically sink 35mA.

    The CMOS MAX8211/MAX8212 are plug-in replacements for the bipolar ICL8211/ICL8212 in most applications. The use of CMOS technology has several advantages. The quiescent supply current is much less than in the bipolar parts. Higher-value resistors can also be used