AIS Baseband IC with/without RF Synthesiser
CMX7032/CMX7042
Figure 5 CMX7042 Power Supply Connections and De-coupling
Component Values as per Table 2.
Notes:
1. It is important to protect the analogue pins from extraneous inband noise and to minimise the impedance
between the CMX7032 and the supply and bias de-coupling capacitors. The supply decoupling capacitors
should be as close as possible to the CMX7032. It is therefore recommended that the printed circuit board
is laid out with separate ground planes for the AV , RFV
and DV
supplies in the area of the
SS
SS
SS
CMX7032, with provision to make links between them, close to the CMX7032. Use of a multi-layer printed
circuit board will facilitate the provision of ground planes on separate layers.
2. The central metal pad (which is exposed on Q1 and Q3 packages only) may be electrically unconnected or,
alternatively, may be connected to Analogue Ground (AV ). No other electrical connection is permitted.
SS
3.
V
is used as an internal reference for detecting and generating the various analogue signals. It must
BIAS
be carefully decoupled to ensure its integrity so, apart from the decoupling capacitor shown, no other loads
should be connected. If V needs to be used to set the discriminator mid-point reference, it must be
BIAS
buffered with an external high input impedance buffer.
4. The 2.5V V
output can be used to supply the 2.5V RFV , to remove the need for an external 2.5V
DEC
DD
regulated supply. VDEC can be directly connected to RFVDD.
2012 CML Microsystems Plc
16
D/7032/42_FI1.2/13
CMLMICRO [ CML MICROCIRCUITS ]
