MAX2602ESA-T

Overview

The MAX2602ESA-T is a silicon bipolar RF power transistor integrated with a thermally matched biasing diode, housed in an 8-pin SO package. It delivers 1W of output power at 900MHz from a 3.6V supply with 58% collector efficiency for constant-envelope applications. For NADC (IS-54) operation, it provides 29dBm output with -28dBc ACPR from a 4.8V supply. The device operates over a DC-to-microwave frequency range with a typical power gain of 11.6dB and noise figure of 3.3dB. It functions without negative bias or supply switches, supporting extended temperature ranges from -40°C to +85°C.

Feature Summary

• Integrated on-chip biasing diode that matches the thermal and process characteristics of the power transistor for accurate collector current control across temperature variations.
• Operates directly from standard battery configurations including one Li-Ion cell or three NiCd/NiMH cells without requiring voltage inverters or sequencing circuitry.
• Eliminates the need for drain switches to turn off the device, thereby increasing operating time by allowing lower end-of-life battery voltages and removing wasted switch power.
• Utilizes low-cost silicon bipolar technology optimized for portable cellular and wireless equipment final stages.

Applications

• Narrow-Band PCS (NPCS)
• 915MHz ISM Transmitters
• Microcellular GSM (Power Class 5)
• AMPS Cellular Phones
• Digital Cellular Phones

Procurement Notes

Verify the specific ordering suffix against official manufacturer documentation to confirm package type and temperature rating. Ensure the component meets RoHS compliance requirements if mandated by your design specifications. Confirm availability through authorized distributors as stock levels may vary. Cross-reference the datasheet revision date to ensure all electrical parameters align with your system requirements before procurement.

Selection Notes

Select the MAX2602ESA-T when a built-in thermal tracking mechanism is required to stabilize collector current without external complex bias networks. This component is suitable for designs needing high efficiency at low supply voltages where GaAsFET alternatives would require additional negative bias generation. Consider the 8-pin SO package constraints for thermal management and PCB layout space compared to other available packages in the series.

Part Context

This component belongs to the MAX2601/MAX2602 family of RF power transistors designed for 900MHz applications. While the MAX2601 lacks the internal diode, the MAX2602 variant specifically includes the biasing diode to simplify thermal compensation. Both devices share similar electrical performance metrics but differ in biasing architecture, making the MAX2602 ideal for applications prioritizing simplified thermal stability.

Replacement Considerations

The MAX2601ESA-T serves as a direct functional substitute if the integrated biasing diode is not required for the specific application. Verify that the replacement part maintains compatibility with the existing PCB footprint and thermal dissipation requirements of the 8-pin SO package.

FAQ

How does the integrated biasing diode in the MAX2602 function?

The diode is a scaled version of the power transistor's base-emitter junction. Current through the diode is proportional to 1/15th of the quiescent collector current, ensuring the transistor's collector current remains constant despite temperature changes.

What are the optimum source and load impedances at 836MHz?

For maximum efficiency at VBB = 0.75V and VCC = 3.6V, the optimum source impedance (ZS) is 5.5 + j2.0 ohms and the load impedance (ZL) is 6.5 + j1.5 ohms.

Why is the backside slug connection critical for this device?

The backside slug connects directly to the PC board ground plane to reduce emitter inductance and serve as the primary thermal path for heat dissipation, which is essential for maintaining performance and reliability.