19-3491; Rev 0; 1/05 Silicon Oscillator with Reset Output The MAX7382 silicon oscillator replaces ceramic resonators, crystals, and crystal-oscillator modules as the clock source for microcontrollers in 3V, 3.3V, and 5V applications. The MAX7382 features a factory-programmed oscillator and a microprocessor (µP) poweron-reset (POR) supervisor. Unlike typical crystal and ceramic-resonator oscillator circuits, the MAX7382 is resistant to vibration and EMI. The high-output-drive current and absence of highimpedance nodes makes the oscillator less susceptible to dirty or humid operating conditions. With a wide operating temperature range as standard, the MAX7382 is a good choice for demanding home appliance and automotive environments. The MAX7382 is available with factory-programmed frequencies ranging from 10MHz to 32MHz. See Table 2 for standard frequencies and contact the factory for custom frequencies. Refer to the MAX7376 data sheet for frequencies less than 10MHz. The MAX7382 is available in a 5-pin SOT23 package. The MAX7382 standard operating temperature range is -40°C to +125°C. See the Applications Information section for extended operating temperature range. Applications Features ♦ 2.7V to 5.5V Operation ♦ 10MHz to 32MHz Oscillator ♦ Integrated POR ♦ ±10mA Clock Output Drive Capability ♦ 2.5% Initial Accuracy ♦ ±50ppm/°C Frequency Drift ♦ 50% Duty Cycle ♦ 5ns Output Rise and Fall Time ♦ Low Jitter: 80psP-P at 16MHz ♦ 4mA Operating Current at 16MHz ♦ -40°C to +125°C Temperature Range ♦ Small 5-Pin SOT23 Package Ordering Information PART* TEMP RANGE PINPACKAGE RESET OUTPUT Active-high MAX7382A_ _ _-T -40°C to +125°C 5 SOT23-5 push-pull White Goods Active-low MAX7382B_ _ _-T -40°C to +125°C 5 SOT23-5 push-pull Automotive MAX7382C_ _ _-T -40°C to +125°C 5 SOT23-5 Open drain Consumer Products *Standard version is shown in bold. The first letter after the part number designates the reset output option. Insert the letter corresponding to the desired reset threshold level from Table 1 in the next position. Insert the two-letter code from Table 2 in the remaining two positions for the desired frequency range. Table 1 and Table 2 are located at the end of the data sheet. Appliances and Controls Handheld Products Portable Equipment Microcontroller Systems Typical Operating Circuit VCC 2.7V TO 5.5V 0.1µF VCC CLOCK OSC1 OSC2 MAX7382 E.C. RST/RST RST µC GND Pin Configuration appears at end of data sheet. ________________________________________________________________ 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 MAX7382 General Description MAX7382 Silicon Oscillator with Reset Output ABSOLUTE MAXIMUM RATINGS VCC to GND ...........................................................-0.3V to +6.0V All Other Pins to GND...................................-0.3V to (V+ + 0.3V) CLOCK, RST Current .......................................................±50mA Continuous Power Dissipation (TA = +70°C) 5-Pin SOT23 (derate 7.1mW/°C above +70°C) ....571mW (U5-2) Operating Temperature Range .........................-55°C to +135°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. ELECTRICAL CHARACTERISTICS (Typical Operating Circuit, VCC = 2.7V to 5.5V, VL = VCC, TA = -40°C to +125°C. Typical values are at VCC = 5.0V, TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER Operating Supply Voltage Operating Supply Current SYMBOL CONDITIONS VCC ICC MIN TYP 2.7 MAX UNITS 5.5 V fCLOCK = 16MHz, TA = -40°C to +125°C, no load 8.7 fCLOCK = 14.7456MHz, TA = -40°C to +125°C, no load 8.0 fCLOCK = 12MHz, TA = -40°C to +125°C, no load 6.5 fCLOCK = 11.0592MHz, TA = -40°C to +125°C, no load 6.0 fCLOCK = 10MHz, TA = -40°C to +125°C, no load 5.4 mA CLOCK OUTPUT Output High Voltage VOH Output Low Voltage VOL Clock Frequency Accuracy fCLOCK VL = 4.5V, ISOURCE = 7.0mA VL = 2.7V, ISOURCE = 2.0mA V VL = 4.5V, ISINK = 20mA 0.4 VL = 2.7V, ISINK = 10mA VCC = 5V, TA = +25°C, deviation from selected frequency -2.5 +2.5 VCC = 2.7V to 5.5V, TA = +25°C, deviation from selected frequency -5.0 +3.5 V % Clock Temperature Coefficient TA = -40°C to +125°C Duty Cycle (Note 2) 2 VL - 0.4 40 ±50 ±350 ppm/°C 50 60 % _______________________________________________________________________________________ Silicon Oscillator with Reset Output (Typical Operating Circuit, VCC = 2.7V to 5.5V, VL = VCC, TA = -40°C to +125°C. Typical values are at VCC = 5.0V, TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER SYMBOL Output Jitter CONDITIONS MIN TYP MAX UNITS Observation of 16MHz for 20s using a 12GHz oscilloscope 80 psP-P Output Rise Time tR 10% to 90% 5 ns Output Fall Time tF 90% to 10% 5 ns Power-On-Reset Threshold Reset Hysteresis VTH HYST Power-On-Reset Delay PORDLY VCC rising, deviation from nominal threshold TA = +25°C -2 +2 TA = -40°C to +125°C -5 +5 Difference between rising and falling thresholds VCC rising from 0 to 5V in 1µs at +25°C % 1 % 122 µs RESET OUTPUT Output High Voltage (Note 3) Output Low Voltage VL = 4.5V, ISOURCE = 7.0mA VCC 0.4 VL = 2.7V, ISOURCE = 2.0mA VCC 0.4 V VOH VOL VL = 4.5V, ISINK = 20mA 0.4 VL = 2.7V, ISOURCE = 10mA 0.4 V Note 1: All parameters tested at TA = +25°C. Specifications over temperature are guaranteed by design. Note 2: Guaranteed by design. Not production tested. Note 3: For push-pull output only. _______________________________________________________________________________________ 3 MAX7382 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (VCC = VL = 5V, TA = +25°C, frequency = 10MHz, unless otherwise noted.) DUTY CYCLE vs. SUPPLY VOLTAGE FREQUENCY = 10MHz 49.0 48.5 MAX7382 toc02 3.25 3.20 SUPPLY CURRENT (mA) 49.5 FREQUENCY = 11.0592MHz 50 DUTY CYCLE (%) 49 48 47 46 45 48.0 -55 -17 21 59 97 3.10 FREQUENCY = 10MHz 3.05 3.00 2.90 2.7 135 3.15 2.95 3.1 3.5 3.9 4.3 4.7 5.1 5.5 -55 -17 21 59 97 TEMPERATURE (°C) SUPPLY VOLTAGE (V) TEMPERATURE (°C) SUPPLY CURRENT vs. SUPPLY VOLTAGE FREQUENCY DEVIATION vs. SUPPLY VOLTAGE FREQUENCY DEVIATION vs. TEMPERATURE 3.0 2.5 FREQUENCY = 11.0592MHz 1.5 1.0 0.5 0 -0.5 -1.0 135 4 MAX7382 toc06 3.5 2.0 FREQUENCY = 10MHz 3 FREQUENCY DEVIATION (%) FREQUENCY = 11.0592MHz FREQUENCY DEVIATION (%) MAX7382 toc04 4.0 MAX7382 toc05 DUTY CYCLE (%) 50.0 SUPPLY CURRENT vs. TEMPERATURE 51 MAX7382 toc01 50.5 MAX7382 toc03 DUTY CYCLE vs. TEMPERATURE SUPPLY CURRENT (mA) MAX7382 Silicon Oscillator with Reset Output 2 1 0 -1 -2 2.0 -3 -1.5 -4 -2.0 1.5 2.7 3.1 3.5 3.9 4.3 4.7 5.1 5.5 2.7 3.1 3.5 3.9 4.3 4.7 5.1 5.5 -55 -17 21 59 SUPPLY VOLTAGE (V) TEMPERATURE (°C) SETTLING TIME FROM START CLOCK OUTPUT WAVEFORM (CL = 10pF) CLOCK OUTPUT WAVEFORM (CL = 10pF) 20ns/div 20ns/div CH1 FREQ 9.992MHz LOW RESOLUTION 10µs/div 135 MAX7382 toc09 MAX7382 toc08 MAX7382 toc07 CHANNEL 1 = CLOCK, CHANNEL 2 = VCC 4 97 SUPPLY VOLTAGE (V) _______________________________________________________________________________________ Silicon Oscillator with Reset Output CLOCK OUTPUT WAVEFORM (CL = 100pF) MAXIMUM TRANSIENT DURATION vs. RESET THRESHOLD OVERDRIVE SUPPLY CURRENT (mA) 0.1 0.01 1m 10m VRESET = 4.32V 4 3 2 100m 1µ 0.04 20ns/div 5 MAX7382 toc11 MAXIMUM TRANSIENT DURATION (s) 1 SUPPLY CURRENT vs. FREQUENCY MAX7382 toc12 MAX7382 toc10 1 0.09 0.14 0.19 0.24 10 11 12 RESET THRESHOLD OVERDRIVE (V) 13 14 15 16 FREQUENCY (MHz) Pin Description PIN NAME 1 CLOCK FUNCTION 2 GND Push-Pull Clock Output Ground 3 RST Reset Output. Open-drain or push-pull output. See the Ordering Information. 4 VCC Positive Supply Voltage. Bypass with a 0.1µF capacitor to GND. 5 E.C. Externally Connected. Connect to Vcc. Detailed Description The MAX7382 is a clock generator with integrated reset for microcontrollers (µCs) and UARTs in 3V, 3.3V, and 5V applications. The MAX7382 is a replacement for crystal-oscillator modules, crystals, or ceramic resonators, and a system reset IC. The clock frequency and reset threshold voltage are factory trimmed to specific values. A variety of popular standard frequencies are available; see Table 2. No external components are required for setting or adjusting the frequency. Oscillator The push-pull clock output drives a load to within 400mV of either supply rail. The clock output remains stable over the full operating voltage range and does not generate short output cycles during either power-on or changing of the frequency. A typical oscillating startup is shown in the Typical Operating Characteristics. _______________________________________________________________________________________ 5 MAX7382 Typical Operating Characteristics (continued) (VCC = VL = 5V, TA = +25°C, frequency = 10MHz, unless otherwise noted.) MAX7382 Silicon Oscillator with Reset Output Applications Information Interfacing to a Microcontroller Clock Input The MAX7382 clock output is a push-pull, CMOS, logic output that directly drives a µP or µC clock input. There are no impedance-matching issues when using the MAX7382. Refer to the microcontroller data sheet for clock input compatibility with external clock signals. The MAX7382 requires no biasing components or load capacitance. When using the MAX7382 to retrofit a crystal oscillator, remove all biasing components from the oscillator input. Table 1. Standard Reset Threshold Levels SUFFIX RESET THRESHOLD (V) X 2.50 V 2.71 R 2.89 standard value Q 3.13 P 3.34 N 3.44 J 3.96 M 4.38 standard value Contact factory for nonstandard reset threshold options. Reset Output The MAX7382 is available with three reset output stage options: push-pull active-low, push-pull active-high, and open-drain active-low. RST is asserted when the monitored input (VCC) drops below the internal VTH- threshold and remains asserted for 120µs after the monitored input exceeds the internal VTH+ threshold. The open-drain RST output requires an external pullup resistor. Table 2. Standard Frequencies SUFFIX STANDARD FREQUENCY (MHz) UK 10 UT 11.0592 VB 12 Output Jitter VT 14.7456 The MAX7382’s jitter performance is given in the Electrical Characteristics table as a peak-to-peak value obtained by observing the output of the MAX7382 for 20s with a 12GHz oscilloscope. Jitter measurements are approximately proportional to the period of the output of the device. Thus, a 10MHz device has approximately twice the jitter value of a 20MHz device. The jitter performance of all clock sources degrades in the presence of mechanical and electrical interference. WB 16 YN 32 VCC 2.7V TO 5.5V MAX7382 POR OSCILLATOR GND RST CLOCK For all other frequency options, contact factory. Table 3. Standard Part Numbers PART RESET THRESHOLD (V) FREQUENCY (MHz) TOP MARK MAX7382CRUK MAX7382CRUT* MAX7382CRVB MAX7382CRVT* MAX7382CRWB MAX7382CRYN* MAX7382CMUK* MAX7382CMUT* MAX7382CMVB MAX7382CMVT* MAX7382CMWB MAX7382CMYN* 2.89 2.89 2.89 2.89 2.89 2.89 4.38 4.38 4.38 4.38 4.38 4.38 10 11.0592 12 14.7456 16 32 10 11.0592 12 14.7456 16 32 AEVU — AEVM — AEVK AEVL — — AEVJ — AEVH AEVI *Contact factory for availability. The MAX7382 is relatively immune to vibration, shock, and EMI influences and thus provides a considerably more robust clock source than crystal or ceramic resonator-based oscillator circuits. Figure 1. Functional Diagram 6 _______________________________________________________________________________________ Silicon Oscillator with Reset Output Extended Temperature Operation The MAX7382 was tested to +135°C during product characterization and shown to function normally at this temperature (see the Typical Operating Characteristics). However, production test and qualification is only performed from -40°C to +125°C at this time. Contact the factory if operation outside this range is required. Power-Supply Considerations Pin Configuration TOP VIEW CLOCK 1 GND 2 5 E.C. 4 VCC MAX7382 RST 3 SOT23 Chip Information TRANSISTOR COUNT: 2937 PROCESS: BiCMOS The MAX7382 operates with a 2.7V and 5.5V powersupply voltage. Good power-supply decoupling is needed to maintain the power-supply rejection performance of the MAX7382. Bypass VCC to GND with a 0.1µF surface-mount ceramic capacitor. Mount the bypassing capacitor as close to the device as possible. If possible, mount the MAX7382 close to the microcontroller’s decoupling capacitor so that additional decoupling is not required. Use a larger value of bypass capacitor recommended if the MAX7382 is to operate with a large capacitive load. Use a bypass capacitor value of at least 1000 times that of the output load capacitance. _______________________________________________________________________________________ 7 MAX7382 Initial Power-Up and Operation An internal power-up reset holds the clock output low until the supply voltage has risen above the power-onreset threshold (VTH+). RST holds the microcontroller in a reset condition until 120µs after the clock has started up. This reset delay ensures that the clock output and the microcontroller’s internal clock circuits have stabilized before the system is allowed to start. Typical microcontroller reset delay ranges from 1ms to 250ms to allow a slow crystal oscillator circuit to start up. The MAX7382 has a fast startup, eliminating the need for such a long reset delay. Silicon Oscillator with Reset Output SOT-23 5L .EPS PACKAGE OUTLINE, SOT-23, 5L 21-0057 E 1 1 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. 8 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2005 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc. MAX7382 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.)