19-3493; Rev 0; 11/04 Silicon Oscillator with Low-Power Frequency Switching and Reset Output Applications White Goods Features ♦ 2.7V to 5.5V Operation ♦ High-Speed Oscillator from 10MHz to 16MHz Low-Speed 32kHz Oscillator Glitch-Free Clock-Speed Switching ♦ 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 ♦ 13µA, 32kHz Operating Current ♦ -40°C to +125°C Temperature Range Ordering Information PART* TEMP RANGE PINPACKAGE RESET OUTPUT MAX7384A_ _ _ -40°C to +125°C 8 µMAX Active high push-pull MAX7384B_ _ _ -40°C to +125°C 8 µMAX Active low push-pull MAX7384C_ _ _ -40°C to +125°C 8 µMAX Open drain *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. Automotive Consumer Products Typical Application Circuit Appliances and Controls VCC 2.7V TO 5.5V Handheld Products Portable Equipment 0.1µF 0.1µF Microcontroller Systems VCC VL CLOCK OSC1 OSC2 MAX7384 E.C. RST/RST RST µC I/O PORT µMAX is a registered trademark of Maxim Integrated Products, Inc. SPEED 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 MAX7384 General Description The MAX7384 dual-speed silicon oscillator replaces ceramic resonators, crystals, and crystal-oscillator modules as the primary and secondary clock source for microcontrollers in 3V, 3.3V, and 5V applications. The MAX7384 features a factory-programmed high-speed oscillator, a 32.768kHz oscillator, a clock-selector input, and a µP power-on-reset (POR) supervisor. The clock output can be switched at any time between the highspeed clock and the 32.768kHz clock for low-power operation. Switchover is synchronized internally to provide glitch-free clock switching. Unlike typical crystal and ceramic-resonator oscillator circuits, the MAX7384 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 MAX7384 is a good choice for demanding home appliance, industrial, and automotive environments. The MAX7384 is available with factory-programmed frequencies ranging from 10MHz to 16MHz. See Table 1 for standard frequencies and contact the factory for custom frequencies. Refer to the MAX7378 data sheet for frequencies less than 10MHz. The MAX7384 is available in an 8-pin µMAX® package. The MAX7384 standard operating temperature range is -40°C to +125°C. See the Applications Information section for extended operating temperature range. MAX7384 Silicon Oscillator with Low-Power Frequency Switching and Reset Output ABSOLUTE MAXIMUM RATINGS VCC to GND ...........................................................-0.3V to +6.0V All Other Pins to GND.................................-0.3V to (VCC + 0.3V) CLOCK, RST Current .......................................................±50mA Input Current (SPEED)......................................................±50mA Continuous Power Dissipation (TA = +70°C) 8-Pin µMAX (derate 4.5mW/°C above +70°C) ...362mW (U8-1) 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 fCLOCK = 32.768kHz, TA = -40°C to +125°C, no load 13 25 mA µA LOGIC INPUTS (SPEED) Input High Voltage VIH Input Low Voltage VIL Input Current IIN 0.7 x VCC V 0.3 x VCC VCC = SPEED = 5.5V 2 µA CLOCK OUTPUT Output High Voltage VOH Output Low Voltage VOL Initial Fast Clock Frequency Accuracy Fast Clock Temperature Coefficient 2 fCLOCK VL = 4.5V, ISOURCE = 7.0mA VL = 2.7V, ISOURCE = 2.0mA VL - 0.4 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 +3.5 V % TA = -40°C to +125°C ±50 _______________________________________________________________________________________ ±350 ppm/°C Silicon Oscillator with Low-Power Frequency Switching and 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 Slow Clock Frequency SYMBOL fCLOCK MIN TYP MAX VCC = 5V, TA = +25°C CONDITIONS 32.268 32.768 33.268 UNITS VCC = 2.7V to 5.5V, TA = +25°C 31.768 32.768 33.768 ±50 ±325 ppm/°C 50 60 % kHz Slow Clock Temperature Coefficient TA = -40°C to +125°C Duty Cycle (Note 2) Output Jitter Observation of 16MHz for 20s using a 12GHz oscilloscope 80 psP-P 5 ns Output Rise Time tR 10% to 90% Output Fall Time tF 90% to 10% Power-On-Reset Threshold VTH Power-On-Reset Hysteresis VHYST Power-On-Reset Delay PORdly VCC rising, deviation from nominal threshold 40 5 ns 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 MAX7384 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (VCC = VL = 5V, TA = +25°C, frequency = 10MHz, unless otherwise noted.) DUTY CYCLE vs. SUPPLY VOLTAGE 50 48.5 49 48 47 46 -17 21 59 97 3.1 TEMPERATURE (°C) SUPPLY CURRENT vs. SUPPLY VOLTAGE FREQUENCY = 11.0592MHz 3.5 3.5 3.9 4.3 4.7 5.1 -55 2.0 2.7 3.1 3.5 3.9 4.3 4.7 5.1 5.5 59 FREQUENCY DEVIATION vs. TEMPERATURE FREQUENCY = 11.0592MHz 4 FREQUENCY = 10MHz 3 PERCENT (%) 0.5 0 -0.5 1 0 -1 -1.0 -2 -1.5 -3 -4 2.7 3.1 3.5 3.9 4.3 4.7 5.1 5.5 -55 -17 21 59 SETTLING TIME FROM START CLOCK OUTPUT WAVEFORM (CL = 10pF) MAX7384 toc08 CLOCK OUTPUT WAVEFORM (CL = 50pF) 135 MAX7384 toc09 CH1 FREQ 9.992MHz LOW RESOLUTION 20ns/div 97 TEMPERATURE (°C) SUPPLY VOLTAGE (V) MAX7384 toc07 20ns/div CHANNEL 1 = CLOCK, CHANNEL 2 = VCC 4 135 2 SUPPLY VOLTAGE (V) 10µs/div 97 FREQUENCY DEVIATION vs. SUPPLY VOLTAGE -2.0 1.5 21 TEMPERATURE (°C) 1.5 PERCENT (%) 2.5 -17 SUPPLY VOLTAGE (V) 1.0 3.0 3.00 5.5 2.0 MAX7384 toc04 4.0 FREQUENCY = 10MHz 3.05 2.90 2.7 135 MAX7384 toc05 -55 3.10 2.95 45 48.0 3.15 MAX7384 toc06 49.0 3.20 SUPPLY CURRENT (mA) FREQUENCY = 10MHz 3.25 MAX7384 toc02 MAX7384 toc01 49.5 FREQUENCY = 11.0592MHz DUTY CYCLE (%) DUTY CYCLE (%) 50.0 SUPPLY CURRENT vs. TEMPERATURE 51 MAX7384 toc03 DUTY CYCLE vs. TEMPERATURE 50.5 SUPPLY CURRENT (mA) MAX7384 Silicon Oscillator with Low-Power Frequency Switching and Reset Output _______________________________________________________________________________________ Silicon Oscillator with Low-Power Frequency Switching and Reset Output CLOCK OUTPUT WAVEFORM (CL = 100pF) HIGH-SPEED TO LOW-SPEED TRANSITION MAXIMUM TRANSIENT DURATION vs. RESET THRESHOLD OVERDRIVE MAX7384 toc10 MAX7384 toc12 MAX7384 toc11 MAXIMUM TRANSIENT DURATION (s) 1 0.1 0.01 1m 10m VRESET = 4.32V 100m 1µ 0.04 20ns/div 0.14 0.09 0.19 10µs/div 0.24 RESET THRESHOLD OVERDRIVE (V) HIGH-SPEED TO LOW-SPEED TRANSITION CHANNEL 1 = CLOCK, CHANNEL 2 = SPEED LOW-SPEED TO HIGH-SPEED TRANSITION LOW-SPEED TO HIGH-SPEED TRANSITION MAX7384 toc13 MAX7384 toc15 MAX7384 toc14 40ns/div 100ns/div 10µs/div CHANNEL 1 = CLOCK, CHANNEL 2 = SPEED CHANNEL 1 = CLOCK, CHANNEL 2 = SPEED CHANNEL 1 = CLOCK, CHANNEL 2 = SPEED SUPPLY CURRENT vs. FREQUENCY SUPPLY CURRENT (mA) MAX7384 toc16 5 4 3 2 1 10 11 12 13 14 15 16 FREQUENCY (MHz) _______________________________________________________________________________________ 5 MAX7384 Typical Operating Characteristics (continued) (VCC = VL = 5V, TA = +25°C, frequency = 10MHz, unless otherwise noted.) Silicon Oscillator with Low-Power Frequency Switching and Reset Output MAX7384 Pin Description PIN NAME 1 VCC FUNCTION 2 VL 3 SPEED 4 RST 5 CLOCK 6 GND Ground 7 E.C. Externally Connected. Connect to Vcc. 8 N.C. No Connection. Not internally connected. Positive Supply Voltage. Bypass VCC to GND with a 0.1µF capacitor. Output Supply Voltage. Bypass VL to GND with a 0.1µF capacitor. VL must be connected to VCC. Clock-Speed Select Input. Drive SPEED low to select the 32kHz fixed frequency. Drive SPEED high to select factory-trimmed frequency. Reset Output. Open-drain or push-pull output. See the Ordering Information. Push-Pull Clock Output Detailed Description The MAX7384 is a dual-speed clock generator with integrated reset for microcontrollers (µCs) and UARTs in 3V, 3.3V, and 5V applications. The MAX7384 is a replacement for crystal-oscillator modules, crystals, or ceramic resonators and a system reset IC. The high-speed clock frequency and reset threshold voltage are factory trimmed to specific values (see Table 1). A variety of popular standard frequencies are available. The lowspeed clock frequency is fixed at 32.768kHz; 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. VCC 2.7V TO 5.5V VL Clock-Speed Selection Drive SPEED low to select slow clock speed (nominally 32.768kHz) or high to select full clock speed. SPEED can be connected to VCC or to GND to select fast or slow clock speed, or connected to a logic output (such as a µP GPIO port) used to change clock speed on the fly. If SPEED is connected to a µP GPIO port, connect a pullup or pulldown resistor to set the clock to the preferred speed on power-up. SPEED input bias current is 2µA (max), so a resistor value as high as 500kΩ can be used. Applications Information Interfacing to a Microcontroller Clock Input The MAX7384 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 MAX7384. Refer to the microcontroller data sheet for clock input compatibility with external clock signals. The MAX7384 requires no biasing components or load capacitance. When using the MAX7384 to retrofit a crystal oscillator, remove all biasing components from the oscillator input. Reset Output POR MAX7384 RST 32kHz (LF OSCILLATOR) SPEED LOGIC MUX 10MHz TO 16MHz (HF OSCILLATOR) GND CLOCK The MAX7384 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. Output Jitter The MAX7384’s jitter performance is given in the Electrical Characteristics table as a peak-to-peak value obtained by observing the output of the MAX7384 for Figure 1. Functional Diagram 6 _______________________________________________________________________________________ Silicon Oscillator with Low-Power Frequency Switching and Reset Output Initial Power-Up and Operation An internal power-up reset asserts RST until the supply voltage has risen above the power-on-reset threshold (VTH+). RST holds the microcontroller in a reset condition until 120µs after VCC has risen above VTH+. 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 MAX7384 has a fast startup, eliminating the need for such a long reset delay. Extended Temperature Operation The MAX7384 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 The MAX7384 operates with a 2.7V and 5.5V powersupply voltage. VCC provides power to the the internal circuitry and VL supplies power to the clock and reset outputs. Good power-supply decoupling is needed to maintain the power-supply rejection performance of the MAX7384. Bypass both V CC and V L to GND with a 0.1µF surface-mount ceramic capacitor. Mount the bypassing capacitors as close to the device as possible. Use a larger value bypass capacitor if the MAX7384 is to operate with a large capacitive load. Use a bypass capacitor value of at least 1000 times that of the output load capacitance. MAX7384 20s with a 12GHz oscilloscope. Jitter measurements are approximately proportional to the output period 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. The MAX7384 is relatively immune to vibration, shock, and EMI influences and thus provides a considerably more robust clock source than crystal or ceramic resonatorbased oscillator circuits. Table 1. Standard Reset Threshold Levels SUFFIX X V R Q P N J M RESET THRESHOLD (V) 2.50 2.71 2.89 Standard value 3.13 3.34 3.44 3.96 4.38 Standard value Contact factory for nonstandard reset threshold options. Table 2. Standard Frequencies SUFFIX STANDARD FREQUENCY (MHz) UK 10 UT 11.0592 VB 12 VT 14.7456 WB 16 For all other frequency options, contact factory. Table 3. Standard Part Numbers PART RESET OUTPUT TYPE RESET FREQUENCY THRESHOLD (MHz) (V) MAX7384CRUK Open drain 2.89 10 MAX7384CRUT Open drain 2.89 11.0592 MAX7384CRVB Open drain 2.89 12 MAX7384CRVT Open drain 2.89 14.7456 MAX7384CRWB Open drain 2.89 16 MAX7384CMUK Open drain 4.38 10 MAX7384CMUT Open drain 4.38 11.0592 MAX7384CMVB Open drain 4.38 12 MAX7384CMVT Open drain 4.38 14.7456 MAX7384CMWB Open drain 4.38 16 _______________________________________________________________________________________ 7 MAX7384 Silicon Oscillator with Low-Power Frequency Switching and Reset Output Pin Configuration Chip Information TRANSISTOR COUNT: 2937 PROCESS: BiCMOS TOP VIEW VCC 1 8 N.C. 7 E.C. 3 6 GND RST 4 5 CLOCK VL 2 SPEED MAX7384 µMAX 8 _______________________________________________________________________________________ Silicon Oscillator with Low-Power Frequency Switching and Reset Output E ÿ 0.50±0.1 8 INCHES DIM A A1 A2 b H c D e E H 0.6±0.1 1 L 1 α 0.6±0.1 S BOTTOM VIEW D MIN 0.002 0.030 MAX 0.043 0.006 0.037 0.014 0.010 0.007 0.005 0.120 0.116 0.0256 BSC 0.120 0.116 0.198 0.188 0.026 0.016 6∞ 0∞ 0.0207 BSC 8LUMAXD.EPS 4X S 8 MILLIMETERS MAX MIN 0.05 0.75 1.10 0.15 0.95 0.25 0.36 0.13 0.18 2.95 3.05 0.65 BSC 2.95 3.05 4.78 5.03 0.41 0.66 0∞ 6∞ 0.5250 BSC TOP VIEW A1 A2 e A c b α L SIDE VIEW FRONT VIEW PROPRIETARY INFORMATION TITLE: PACKAGE OUTLINE, 8L uMAX/uSOP APPROVAL DOCUMENT CONTROL NO. 21-0036 REV. J 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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________ 9 © 2004 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. MAX7384 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.)