RFICs supplier SST Communications, a subsidiary of Silicon Storage Technology, Inc., has introduced two new high-efficiency power amplifiers for 802.11a and 802.11b/g WLAN systems. Both devices offer low power consumption, as well as on-chip power detection to provide efficiency and cost savings to designers of power-sensitive WLAN equipment, such as PCMCIA, MiniPCI and USB cards, and handheld computing and communications devices.

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The new power amplifiers include the SST12LP14A for 2.4 GHz 802.11b/g and the SST11LP11 for 5 GHz 802.11a. When configured for high-efficiency operation, the versatile SST12LP14A only requires a low-quiescent current (Icq) of 45 mA. It provides 29 dB gain and linear output power of 17 dBm at Icc of 85 mA. Under high-power configuration, the same device provides Pout of 22 dBm at 210 mA for 802.11g and Pout of 23 dBm at 240 mA for 802.11b application, respectively. It offers excellent linearity of approximately 4% added EVM (error vector magnitude) at 22 dBm output power, which is essential for 54 Mbps 802.11g operation while meeting the standard’s spectrum mask at +24 dBm.

Designed to operate over the entire 802.11a band between 4.9-5.8 GHz, the SST11LP11 requires Icq of 80 mA. It consumes 180 mA when delivering 24 dB gain and 18 dBm output power across the entire 4.9-5.8 GHz band with 4% added EVM.

The SST12LP14A power amplifier features a load-insensitive, on-chip power detector with detection ranging from 0.6-1.8 V to cover 0-23 dBm output power with dB-wise linearization and high stability over temperature (<±0.3 dB over 0-85°C), frequency (<±0.3 dB across channel 1-14), and output load (<±0.4 dB with a 2:1 VSWR mismatch load at all angles). Likewise, the SST11LP11 features on-chip power detector ranges from 0.6-2.0 V to cover 0-20 dBm output power, with <±0.5 dB over -10-+85°C temperature stability. In addition to the on-chip power detectors, the SST12LP14a and the SST11LP11 also feature high-speed (less than 200 ns) power up/down control through a single combined reference voltage pin. The ultra-low reference current of the devices (Iref of 2 mA for the SST12LP14A and 14 mA for the SST11LP11) allows them to be controlled by on/off switching signals directly from the baseband chip, thus resulting in further power consumption savings.

The power amplifiers are manufactured using a reliable InGaP/GaAs HBT technology, with tested MTTF exceeding 6x10⁸ hours at 100°C. The SST12LP14A and the SST11LP11 are available now in production quantities. Pricing for the SST12LP14A devices start at $0.45 and pricing for the SST11LP11 devices start at $0.70, each in 10K unit quantities. The SST12LP14A is pin-compatible to the SST12LP14 and is offered in a 3 mm x 3 mm, 16-pin LCC (leadless chip carrier) package. The SST11LP11 is offered in a 3 mm x 3 mm, 16-pin VQFN (very thin quad flat no-lead) package. Both devices are also offered in lead-free packages.