MAX8520:Smallest TEC Power Drivers for Optical Modules

Industry's Smallest TEC Drivers for SFF/SFP Modules Reduce Heat Generation by 50%

The MAX8520/MAX8521 are designed to drive thermoelectric coolers (TECs) in space-constrained optical modules. Both devices deliver ±1.5A output current and control the TEC current to eliminate harmful current surges. On-chip FETs minimize external components and high switching frequency reduces the size of external components. The MAX8520/MAX8521 operate from a single supply and bias the TEC between the outputs of two synchronous buck regulators. This operation allows for temperature control without "dead zones" or other nonlinearities at low current. This arrangement ensures that the control system does not hunt when the set-point is very close to the natural operating point, requiring a small amount of heating or cooling. An analog control signal precisely sets the TEC current. Both devices feature accurate, individually-adjustable heating current limit and cooling current limit along with maximum TEC voltage limit to improve the reliability of optical modules. 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 TQFN package and its switching frequency is adjustable up to 1MHz through an external resistor. The MAX8521 is also available in a 5mm x 5mm TQFN as well as space-saving 3mm x 3mm UCSP™ and 36-bump WLP (3mm x 3mm) packages, with a pin-selectable switching frequency of 500kHz or 1MHz.

Key Features
  • Circuit Footprint of 0.31in²
  • Low-Profile Design
  • On-Chip Power MOSFETs
  • High-Efficiency Switch-Mode Design
  • Ripple Cancellation for Low Noise
  • Direct Current Control Prevents TEC Current Surges
  • 5% Accurate Adjustable Heating/Cooling Current Limits
  • 2% Accurate TEC Voltage Limit
  • No Dead Zone or Hunting at Low Output Current
  • ITEC Monitors TEC Current
  • 1% Accurate Voltage Reference
  • Switching Frequency Up to 1MHz
  • Synchronization (MAX8521)
MAX8520, MAX8521: Typical Operating Circuit
MAX8520, MAX8521: Typical Operating Circuit
  • Automated Test Equipment (ATE)
  • Biotech Lab Equipment
  • Fiber Optic Network Equipment
  • Fiber-Optic Laser Modules
  • SFF/SFP Modules
titleDownload file
MAX8520-MAX8521 Data SheetMAX8520-MAX8521.pdf
Part NumberPrimary TopologyMonitor/Control FeaturesDC-DC/Power FeaturesVIN
Oper. Freq.
Inverting OutputsPackage/PinsBudgetary
minmaxminmaxSee Notes
MAX8520H-BridgeOutput OVP
Volt. or PWM Controlled Output
Adj. Frequency
Avg. Current Mode Control
Current Limit
Fixed Freq./PWM
Internal Switch
Soft Start
Sync. Rectifier
TEC Driver
35.5-$8.42 @1k
MAX8521Avg. Current Mode Control
Current Limit
Fixed Freq./PWM
Internal Switch
Soft Start
Sync. Rectifier
TEC Driver
$5.23 @1k
Design kits & evaluation modules
Quality and Environmental Data
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX8520ETPNo Longer AvailableMAX8520ETP+TQFN,;20 pin;26 mm²-40°C to +85°CNo
MAX8520ETP+ActiveTQFN,;20 pin;26 mm²-40°C to +85°CLead Free
MAX8520ETP+TActiveTQFN,;20 pin;26 mm²-40°C to +85°CLead Free
MAX8520ETP-TNo Longer AvailableMAX8520ETP+TTQFN,;20 pin;26 mm²-40°C to +85°CNo
MAX8520ETP/GG8ActiveMAX8520ETP+TQFN,;20 pin;26 mm²-40°C to +85°CNo
MAX8520EVKITActiveEVKIT;-40°C to +85°CSee data sheet
MAX8520-MAX8521.pdf MAX8521
Stabilizing Thermoelectric Controller (TEC) Loops Using a Unit-Step Response MAX8521
HFTA-12.0: Measuring Crosstalk Penalty in High-Speed Bidirectional Serial Communication Modules DS1862
HFAN-08.2.0: How to Control and Compensate a Thermoelectric Cooler (TEC) MAX4477
Compact DWDM laser Temperature Control with the MAX8521 MAX5144
MAX8520.pdf MAX8520
典型工作电路 MAX8521