MAX8520 MAXIM [Maxim Integrated Products], MAX8520 Datasheet
MAX8520
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MAX8520 Summary of contents
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... An analog output signal monitors the TEC current. A unique ripple cancellation scheme helps reduce noise. The MAX8520 is available in a 5mm x 5mm thin QFN package and its switching frequency is adjustable up to 1MHz through an external resistor. The MAX8521 is also available in a 5mm x 5mm thin QFN, as well as a space- saving 3mm x 3mm UCSP™ ...
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Smallest TEC Power Drivers for Optical Modules ABSOLUTE MAXIMUM RATINGS V to GND ..............................................................-0.3V to +6V DD SHDN, MAXV, MAXIP, MAXIN, CTLI to GND .........................................................-0.3V to +6V COMP, FREQ, OS1, OS2, CS, REF, ITEC to GND...........................................-0. ...
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... MAX8521, FREQ MAX8520 60kΩ, V EXT DD f SW-INT MAX8520 60kΩ, V EXT DD MAX8520 150kΩ, V EXT MAX8520 150kΩ, V EXT 25% < duty cycle <75% (MAX8521 only) (Note OS2 FREQ applicable for the SHDN ...
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... MAX8521, FREQ = MAX8520 60kΩ EXT DD MAX8520 60kΩ EXT DD MAX8520 150kΩ EXT DD MAX8520 150kΩ EXT DD 25% < duty cycle <75% (MAX8521 only) (Note OS2 FREQ applicable for the MAX8521 DD ...
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... CTLI Input Resistance Error-Amp Transconductance V Accuracy ITEC Note 3: Enter 1MHz mode by tying a 60kΩ resistor from FREQ to ground for the MAX8520, and tying FREQ to V Note 4: Includes PFET leakage. Note 5: Duty-cycle specification is guaranteed by design and not production tested. Note 6: CTLI Gain is defined as: ∆ ...
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... TEC 400ns/div ZERO-CROSSING TEC CURRENT MAX8520/21 toc08 V CTLI I00mV/div 1. TEC 100mA/div 1ms/div 1100 1000 900 800 700 600 500 400 - TEC CURRENT RIPPLE MAX8520/21 toc06 400ns/div V vs. TEC CURRENT ITEC 3.0 2.5 2.0 1.5 1.0 0.5 0 -2.0 -1.5 -1.0 -0.5 0 0.5 1.0 1.5 2.0 TEC CURRENT (A) SWITCHING FREQUENCY vs. TEMPERATURE FREQ = 1MHz ...
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... Optical Modules REFERENCE VOLTAGE CHANGE vs. V EXT 0.6 REF SOURCING 150µA 0.4 0.2 0.0 -0.2 -0.4 -0.6 -0.8 -1.0 -1.2 -1.4 160 3.0 3.5 4.0 4.5 V (V) DD STARTUP AND SHUTDOWN WAVEFORMS 1.0 200µs/div V STEP RESPONSE DD MAX8520/21 toc19 V DD 2V/div TEC 10mA/div 10ms/div DD 5.0 5.5 MAX8520/21 toc17 V SHDN 5V/div 200mA/div 0mA I TEC 500mA/div 0mA 7 ...
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... To lower this limit, connect MAXV to a resistor-divider network from REF to DD GND. The maximum TEC voltage is equal 1.50V Reference Output. Bypass REF to GND with a 0. 1µF ceramic capacitor. THERMAL STABILITY, HEATING MODE MAX8520/21 toc22 TEMPERATURE 0.001°C/div T = +25°C TEC T = +5° ...
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... Analog Ground. Start connect to PGND at underside exposed pad for QFN package Analog Supply Voltage Input. Bypass V DD For MAX8520: Analog FREQ Set Pin (see the Switching Frequency section). For MAX8521: Digital FREQ Selection Pin. Tie FREQ 500kHz operation. The PWM oscillator can synchronize to FREQ by switching at FREQ between 700kHz and 1 ...
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... R a known supply voltage. Voltage and Current-Limit Setting Both the MAX8520 and MAX8521 provide control of the maximum differential TEC voltage. Applying a voltage to MAXV limits the maximum voltage across the TEC. The voltage at MAXIP and MAXIN sets the maximum positive and negative current through the TEC ...
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1µ 1µF PGND1 1µF PGND2 REF C6 0.1µF MAXIP MAXIN 49.9kΩ MAXV 100kΩ CTLI 243kΩ Figure 1. MAX8521 Typical Application Circuit ______________________________________________________________________________________ Smallest TEC Power Drivers for ...
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... 1µ 1µF PGND1 PV C4 1µF PGND2 REF C6 0.1µF MAXIP MAXIN 49.9kΩ MAXV 100kΩ Figure 2. Typical Application Circuit for the MAX8520 with Reduced Op-Amp Count Configuration 12 ______________________________________________________________________________________ L1 4.7µF LX1 SENSE 0.09Ω OS1 C5 10µ MAX8520 ...
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... R 0.5X Figure 3. Functional Diagram of the Current-Control Loop Inductor Selection The MAX8520/MAX8521 dual buck converters operate in phase and in complementary mode to drive the TEC differentially in a current-mode control scheme. At zero TEC current, the differential voltage is zero; hence, the outputs with respect to GND are equal to half of V ...
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... Decouple each power-supply input ( with a 1µF ceramic capacitor close to the supply DD pins. In applications with long distances between the source supply and the MAX8520/MAX8521, additional 14 ______________________________________________________________________________________ bypassing may be needed to stabilize the input supply. In such cases, a low-ESR electrolytic or ceramic capaci- tor of 100µF or more compensation capacitor is needed to ensure current- control-loop stability (see Figure 3) ...
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... OS2 OS1 The MAX8520/MAX8521 can be placed in a power-saving shutdown mode by driving SHDN low. When the MAX8520/MAX8521 are shut down, the TEC is off (OS1 and OS2 decay to GND) and supply current is reduced to 2mA (typ). ITEC is a status output that provides a voltage proportional to the actual TEC current ...
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... TOP VIEW LX1 1 PGND1 2 MAX8520/ SHDN 3 MAX8521 COMP 4 ITEC 5 THIN QFN 16 ______________________________________________________________________________________ Refer to the MAX8520/MAX8521 evaluation kit for a PC board layout example. TRANSISTOR COUNT: 3007 PROCESS: BiCMOS LX2 E6 14 PGND2 LX2 D6 13 FREQ PGND2 PGND2 PGND2 PGND1 PGND1 PGND1 12 ...
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... SENSE MAX I = TEC MAXIN ) × MAXIN REF (0.15V/R ) SENSE CS ITEC OS1 REF CTLI COMP GND MAX8520/ MAX8521 FREQ (MAX8520) ______________________________________________________________________________________ Optical Modules Functional Diagram FREQ (MAX8521 LX1 PWM CONTROL PGND1 AND GATE CONTROL CS OS1 OS2 LX2 PGND2 ...
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Smallest TEC Power Drivers for Optical Modules (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) 18 ______________________________________________________________________________________ Package Information ...
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For the latest package outline information www.maxim-ic.com/packages.) Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim ...