MAX1978/MAX1979 Integrated Temperature Controllers for Peltier Modules General Description Features Smallest, Safest, Most Accurate Complete The MAX1978/MAX1979 are the smallest, safest, most Single-Chip Controller accurate complete single-chip temperature controllers for Peltier thermoelectric cooler (TEC) modules. On-chip power On-Chip Power MOSFETSNo External FETs FETs and thermal control-loop circuitry minimize external 2 Circuit Footprint < 0.93in components while maintaining high efficiency. Selectable Circuit Height < 3mm 500kHz/1MHz switching frequency and a unique ripple-can- cellation scheme optimize component size and efficiency Temperature Stability to 0.001C while reducing noise. Switching speeds of internal Integrated Precision Integrator and Chopper MOSFETs are optimized to reduce noise and EMI. An ultra- Stabilized Op Amps low-drift chopper amplifier maintains 0.001C temperature Accurate, Independent Heating and Cooling stability. Output current, rather than voltage, is directly con- Current Limits trolled to eliminate current surges. Individual heating and Eliminates Surges By Directly Controlling cooling current and voltage limits provide the highest level of TEC Current TEC protection. Adjustable Differential TEC Voltage Limit The MAX1978 operates from a single supply and provides Low-Ripple and Low-Noise Design bipolar 3A output by biasing the TEC between the outputs of two synchronous buck regulators. True bipolar operation TEC Current Monitor controls temperature without dead zones or other nonlin- Temperature Monitor earities at low load currents. The control system does not Over- and Undertemperature Alarm hunt when the set point is very close to the natural operating point, where only a small amount of heating or cooling is Bipolar 3A Output Current (MAX1978) needed. An analog control signal precisely sets the TEC Unipolar +6A Output Current (MAX1979) current. The MAX1979 provides unipolar output up to 6A. Ordering Information A chopper-stabilized instrumentation amplifier and a high- precision integrator amplifier are supplied to create a pro- PART TEM P R A N G E PIN-PACKAGE portional-integral (PI) or proportional-integral-derivative (PID) MAX1978ETM+ -40 C to +85 C 48 Thin QFN-EP* controller. The instrumentation amplifier can interface to an MAX1979ETM+ -40 C to +85 C 48 Thin QFN-EP* external NTC or PTC thermistor, thermocouple, or semicon- ductor temperature sensor. Analog outputs are provided to *EP = Exposed pad. +Denotes a lead(Pb)-free/RoHS-compliant package. monitor TEC temperature and current. In addition, separate Functional Diagrams overtemperature and undertemperature outputs indicate Pin Configuration when the TEC temperature is out of range. An on-chip volt- age reference provides bias for a thermistor bridge. TOP VIEW The MAX1978/MAX1979 are available in a low-profile 48-lead thin QFN-EP package and is specified over the 1 36 -40C to +85C temperature range. The thermally OS2 + FREQ N.C. 2 35 N.C enhanced QFN-EP package with exposed metal pad 34 PGND2 3 PGND1 minimizes operating junction temperature. An evaluation 4 33 LX1 LX2 kit is available to speed designs. PGND2 5 32 PGND1 LX2 31 6 LX1 MAX1978 Applications PV 2 7 30 PV 1 DD MAX1979 DD N.C. 8 29 N.C. Fiber Optic Laser Modules 28 LX2 9 LX1 PV 2 10 27 PV 1 DD DD WDM, DWDM Laser-Diode Temperature Control SHDN 11 26 GND 25 GND OT 12 Fiber Optic Network Equipment EDFA Optical Amplifiers Telecom Fiber Interfaces Pin Configurations appear at end of data sheet. ATE TQFN-EP Functional Diagrams continued at end of data sheet. *ELECTRICALLY CONNECTED TO THE UNDERSIDE METAL SLUG. UCSP is a trademark of Maxim Integrated Products, Inc.Typical Operating Circuit appears at end of data sheet. NOTE: GND IS CONNECTED TO THE UNDERSIDE METAL SLUG. For pricing, delivery, and ordering information, please contact Maxim Direct 19-2490 Rev 3 3/10 at 1-888-629-4642, or visit Maxims website at www.maxim integrated.com. Pin Configuration Typical Operating Circuit appears at end of data sheet. AVAILABLE 48 UT 13 OS1 INTOUT 14 47 CS INT- 15 46 REF 45 GND 16 CTLI DIFOUT 17 44 V DD FB- 18 43 GND FB+ 19 42 GND 20 41 BFB- MAXV BFB+ 21 40 MAXIN 22 39 AIN+ MAXIP 23 38 COMP AIN- AOUT 24 37 ITECMAX1978/MAX1979 Integrated Temperature Controllers for Peltier Modules ABSOLUTE MAXIMUM RATINGS V to GND..............................................................-0.3V to +6V Peak LX Current (MAX1978) (Note 1).................................4.5A DD SHDN, MAXV, MAXIP, MAXIN, Peak LX Current (MAX1979) (Note 1)....................................+9A Continuous Power Dissipation (T = +70C) CTLI, OT, UT to GND............................................-0.3V to +6V A 48-Lead Thin QFN-EP FREQ, COMP, OS1, OS2, CS, REF, ITEC, AIN+, AIN-, (derate 26.3mW/C above +70C) (Note 2).................2.105W AOUT, INT-, INTOUT, BFB+, BFB-, FB+, FB-, Operating Temperature Ranges DIFOUT to GND......................................-0.3V to (V + 0.3V) DD MAX1978ETM ..................................................-40C to +85C PV 1, PV 2 to V ...........................................-0.3V to +0.3V DD DD DD MAX1979ETM ..................................................-40C to +85C PV 1, PV 2 to GND...............................-0.3V to (V + 0.3V) DD DD DD Maximum Junction Temperature .....................................+150C PGND1, PGND2 to GND .......................................-0.3V to +0.3V Storage Temperature Range .............................-65C to +150C COMP, REF, ITEC, OT, UT, INTOUT, DIFOUT, Lead Temperature (soldering, 10s) .................................+300C BFB-, BFB+, AOUT Short to GND .............................Indefinite Note 1: LX has internal clamp diodes to PGND and PVDD. Applications that forward bias these diodes should not exceed the ICs package power dissipation limits. Note 2: Solder underside metal slug to PCB ground plane. 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 (V = PV 1 = PV 2 = V = 5V, FREQ = GND, CTLI = FB+ = FB- = MAXV = MAXIP = MAXIN = REF, T = 0C to +85C, DD DD DD SHDN A unless otherwise noted. Typical values at T = +25C.) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Input Supply Range V 3.0 5.5 V DD V = 5V, I = 0 to 3A, DD TEC -4.3 +4.3 V = V - V (MAX1978) OUT OS1 OS2 V = 5V, I = 0 to 6A, DD TEC 4.3 V = V (MAX1979) OUT OS1 Output Voltage Range V V OUT V = 3V, I = 0 to 3A, DD TEC -2.3 +2.3 V = V - V (MAX1978) OUT OS1 OS2 V = 3V, I = 0 to 6A, DD TEC 2.3 V = V (MAX1979) OUT OS1 MAX1978 3 Maximum TEC Current I A TEC(MAX) MAX1979 6 Reference Voltage V V = 3V to 5.5V, I = 150A 1.485 1.500 1.515 V REF DD REF Reference Load Regulation V V = 3V to 5.5V, I = +10A to -1mA 1.2 5 mV REF DD REF V = V 135 150 160 MAXI REF V < V OS1 CS V = V /3 40 50 60 MAXI REF Current-Sense Threshold mV V = V 135 150 160 MAXI REF V > V OS1 CS V = V /3 40 50 60 MAXI REF V = 5V, I = 0.5A 0.04 0.07 DD NFET On-Resistance R DS(ON-N) V = 3V, I = 0.5A 0.06 0.08 DD V = 5V, I = 0.5A 0.06 0.10 DD PFET On-Resistance R DS(ON-P) V = 3V, I = 0.5A 0.09 0.12 DD V = V = 5V, T = +25C 0.02 10 LX DD A NFET Leakage I A LEAK(N) V = V = 5V, T = +85C1 LX DD A 2 Maxim Integrated