Philips BGM1012 specifications Application Information, MMIC wideband amplifier

Philips Semiconductors	Product specification
MMIC wideband amplifier	BGM1012

APPLICATION INFORMATION

Figure 2 shows a typical application circuit for the BGM1012 MMIC. The device is internally matched to

50 Ω, and therefore does not need any external matching. The value of the input and output DC blocking capacitors C2 and C3 should not be more than 100 pF for applications above 100 MHz. However, when the device is operated below 100 MHz, the capacitor value should be increased.

The nominal value of the RF choke L1 is 100 nH. At frequencies below 100 MHz this value should be increased to 220 nH. At frequencies above 1 GHz a much lower value (e.g. 10 nH) can be used to improve return losses. For optimal results, a good quality chip inductor such as the TDK MLG 1608 (0603), or a wire-wound SMD type should be chosen.

Both the RF choke L1 and the 22 nF supply decoupling capacitor C1 should be located as closely as possible to the MMIC.

Separate paths must be used for the ground planes of the ground pins GND1 and GND2, and these paths must be as short as possible. When using vias, use multiple vias per pin in order to limit ground path inductance.

handbook,V halfpage
s
	C1		Vs			L1
RF input		RF in			RF out		RF output
	C2					C3
		GND1		GND2			MGU436

Fig.2 Typical application circuit.

Figure 3 shows two cascaded MMICs. This configuration doubles overall gain while preserving broadband characteristics. Supply decoupling and grounding conditions for each MMIC are the same as those for the circuit of Fig.2.

The excellent wideband characteristics of the MMIC make it an ideal building block in IF amplifier applications such as LBNs (see Fig.4).

As a buffer amplifier between an LNA and a mixer in a receiver circuit, the MMIC offers an easy matching, low noise solution (see Fig.5).

In Fig.6 the MMIC is used as a driver to the power amplifier as part of a transmitter circuit. Good linear performance and matched input and output offer quick design solutions in such applications.

DC-block	DC-block	DC-block
handbook, halfpage
100 pF	100 pF	100 pF
input			output
			MGU437

Fig.3 Easy cascading application circuit.

handbook, halfpage	mixer
		to IF circuit
from RF
circuit		or demodulator
	wideband
	amplifier	MGU438
	oscillator

Fig.4 Application as IF amplifier.

handbook, halfpage		mixer
		to IF circuit
antenna
		or demodulator
LNA	wideband
	amplifier	MGU439
	oscillator

Fig.5 Application as RF amplifier.

mixer

handbook, halfpage	to power
from modulation
or IF circuit	amplifier
wideband
amplifier	MGU440
oscillator

Fig.6 Application as driver amplifier.

2002 Sep 06 5