MAX3514

The MAX3514/MAX3516/MAX3517 programmable-gain amplifiers are designed for use in CATV upstream applications. The MAX3514/MAX3517 drive up to +61dBmV (QPSK) into a 75 load when driven with a +34dBmV nominal input signal. The MAX3516 drives up to +64dBmV (QPSK). Both input and output ports are differential, requiring that an external balun be used at the output port. The variable gain feature provides greater than 56dB of dynamic range, which is controlled by an SPI™ 3-wire interface. Gain control is available in 0.5dB steps. The MAX3514 operate over a frequency range of 5MHz to 65MHz.

The MAX3514 is a pin-for-pin compatible upgrade for the MAX3510. Like the MAX3510, the MAX3514 is internally matched for use with a 2:1 (voltage ratio) balun. The MAX3517 utilizes an external output resistor for greater load-matching flexibility, and offers the same performance as the MAX3514. The MAX3516 is a higher power version of the MAX3514 with 3dB more gain and output power capability, and is offered in a smaller thermally enhanced TSSOP-EP package.

These MAX3514 operate from a single +5V DC supply and draw 120mA during transmit (100% duty cycle, +61dBmV out). The bias current is automatically adjusted based on the output level to increase efficiency. Additionally, the MAX3514 are shut off between bursts to minimize noise and save power while still maintaining a match at the output port. Shutdown mode disables all circuitry and reduces current consumption to 10A (typ).

The MAX3514/MAX3517 are available in a 20-pin QSOP package and the MAX3516 is available in a 20-pin TSSOP-EP package. All devices operate in the extended industrial temperature range (-40°C to +85°C).