MAX1978:Integrated Temperature Controllers for Peltier Modules

The MAX1978/MAX1979 are the smallest, safest, most accurate complete single-chip temperature controllers for Peltier thermoelectric cooler (TEC) modules. On-chip power FETs and thermal control-loop circuitry minimize external components while maintaining high efficiency. Selectable 500kHz/1MHz switching frequency and a unique ripple-cancellation scheme optimize component size and efficiency while reducing noise. Switching speeds of internal MOSFETs are optimized to reduce noise and EMI. An ultra-low-drift chopper amplifier maintains ±0.001°C temperature stability. Output current, rather than voltage, is directly controlled to eliminate current surges. Individual heating and cooling current and voltage limits provide the highest level of TEC protection. The MAX1978 operates from a single supply and provides bipolar ±3A output by biasing the TEC between the outputs of two synchronous buck regulators. True bipolar operation controls temperature without "dead zones" or other nonlinearities at low load currents. The control system does not hunt when the set point is very close to the natural operating point, where only a small amount of heating or cooling is needed. An analog control signal precisely sets the TEC current. The MAX1979 provides unipolar output up to 6A. A chopper-stabilized instrumentation amplifier and a high-precision integrator amplifier are supplied to create a proportional-integral (PI) or proportional-integral-derivative (PID) controller. The instrumentation amplifier can interface to an external NTC or PTC thermistor, thermocouple, or semiconductor temperature sensor. Analog outputs are provided to monitor TEC temperature and current. In addition, separate overtemperature and undertemperature outputs indicate when the TEC temperature is out of range. An on-chip voltage reference provides bias for a thermistor bridge. The MAX1978/MAX1979 are available in a low-profile 48-lead thin QFN-EP package and is specified over the -40°C to +85°C temperature range. The thermally enhanced QFN-EP package with exposed metal pad minimizes operating junction temperature. An evaluation kit is available to speed designs.

Key Features
  • Smallest, Safest, Most Accurate Complete Single-Chip Controller
  • On-Chip Power MOSFETS—No External FETs
  • Circuit Footprint < 0.93in²
  • Circuit Height < 3mm
  • Temperature Stability to 0.001°C
  • Integrated Precision Integrator and Chopper Stabilized Op Amps
  • Accurate, Independent Heating and Cooling Current Limits
  • Eliminates Surges By Directly Controlling TEC Current
  • Adjustable Differential TEC Voltage Limit
  • Low-Ripple and Low-Noise Design
  • TEC Current Monitor
  • Temperature Monitor
  • Over- and Undertemperature Alarm
  • Bipolar ±3A Output Current (MAX1978)
  • Unipolar +6A Output Current (MAX1979)
MAX1978, MAX1979: Typical Operating Circuit
MAX1978, MAX1979: Typical Operating Circuit
Applications/Uses
  • Automated Test Equipment (ATE)
  • EDFA Optical Amplifiers
  • Fiber Optic Network Equipment
  • Fiber-Optic Laser Modules
  • Telecom Fiber Interfaces
  • WDM, DWDM Laser Diode Temperature Control
DataSheet
titleDownload file
MAX1978-MAX1979 Data SheetMAX1978-MAX1979.pdf
Parametrics
Part NumberPrimary TopologyMonitor/Control FeaturesDC-DC/Power FeaturesVIN
(V)
VIN
(V)
VOUT
(V)
VOUT
(V)
Max. IOUT
(A)
Max. IOUT
(A)
Oper. Freq.
(kHz)
Inverting OutputsPackage/PinsBudgetary
Price
minmaxminmaxSee Notes
MAX1978H-BridgeShutdown
Volt. or PWM Controlled Output
Avg. Current Mode Control
Current Limit
Dual/ Multi-Phase
Fixed Freq./PWM
Internal Switch
Soft Start
Sync. Rectifier
TEC Driver
35.5-4.34.36610001TQFN/48$14.22 @1k
MAX1979Avg. Current Mode Control
Current Limit
Dual/ Multi-Phase
Fixed Freq./PWM
Internal Switch
Soft Start
TEC Driver
TQFN/48
Design kits & evaluation modules
Quality and Environmental Data
Related Products
  • MAX1968:Power Drivers for Peltier TEC Modules
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX1978ETMNo Longer AvailableMAX1978ETM+TQFN,;48 pin;50.4 mm²-40°C to +85°CNo
MAX1978ETM+ActiveTQFN,;48 pin;50.4 mm²-40°C to +85°CLead Free
MAX1978ETM+TActiveTQFN,;48 pin;50.4 mm²-40°C to +85°CLead Free
MAX1978ETM-TNo Longer AvailableMAX1978ETM+TQFN;48 pin-40°C to +85°CSee data sheet
MAX1978-MAX1979.pdf MAX1979
HFAN-08.2.0: How to Control and Compensate a Thermoelectric Cooler (TEC) MAX4477
MAX1978.pdf MAX1978
典型工作电路 MAX1979