micrf004 Micrel Semiconductor, micrf004 Datasheet - Page 3

• Manufacturer Part Number: micrf004
• Description: Micrf004/micrf044 Qwikradio? Low-power Vhf Receiver
• Manufacturer: Micrel Semiconductor

Pin Description
February 9, 2000
MICRF004/RF044
Pin Number
16-Pin Pkg.
2, 3
10
11
12
13
14
15
16
1
4
5
6
7
8
9
Pin Number
8-Pin Pkg.
1
2
3
4
5
6
7
8
Pin Name
REFOSC
WAKEB
VSSRF
VDDRF
VDDBB
VSSBB
SWEN
CAGC
SHUT
SEL0
SEL1
ANT
CTH
NC
DO
Pin Function
Bandwidth Selection Bit 0 (Input): Configure with SEL1 to set the desired
demodulator filter bandwidth. See Table 1. Internally pulled-up to VDDRF.
RF [Analog] Return (Input): Ground return to the RF section power supply.
See “Application Information” for bypass capacitor details.
Antenna (Input): High-impedance, internally ac coupled receiver input.
Connect this pin to the receive antenna. This FET gate input has approxi-
mately 2pF of shunt (parasitic) capacitance. See “Applications Information”
for optional band-pass filter information.
RF [Analog] Supply (Input): Positive supply input for the RF section of the
IC. VDDBB and VDDRF should be connected together directly at the IC
pins. Connect a low ESL, low ESR decoupling capacitor from this pin to
VSSRF, as short as possible.
Base-Band [Digital] Supply (Input): Positive supply input for the baseband
section of the IC. VDDBB and VDDRF should be connected together at the
IC pins.
[Data Slicing] Threshold Capacitor (External Component): Capacitor
extracts the dc average value from the demodulated waveform which
becomes the reference for the internal data slicing comparator. See “Appli-
cations Information” for selection.
not internally connected
Base-Band [Digital] Return (Input): Ground return to the baseband section
power supply. See “Application Information” for bypass capacitor and layout
details.
Digital Output (Output): CMOS-level compatible data output signal.
Shutdown (Input): Shutdown-mode logic-level control input. Pull low to
enable the receiver. This input has an internal pulled-up to VDDRF.
Wakeup (Output): Active-low output that indicates detection of an incoming
RF signal. Signal is determined by monitoring for data preamble. CMOS-
level compatible.
AGC Capacitor (External Component): Integrating capacitor for on-chip
AGC (automatic gain control). The decay/attack time-constant ( ) ratio is
nominally 10:1. See “Applications Information” for capacitor selection.
Bandwidth Selection Bit 1 (Input): Configure with SEL0, programs to set the
desired demodulator filter bandwidth. See Table 1. Internally pulled-up to
VDDRF.
Reference Oscillator (External Component or Input): Timing reference for
on-chip tuning and alignment. Connect either a ceramic resonator or crystal
(mode dependent, see “Application Information”). between this pin and
VSSBB, or drive the input with an ac-coupled 0.5Vpp input clock.
Sweep-Mode Enable (Input): Sweep- or fixed-mode operation control input.
When VSWEN is high, the MICRF004 is in sweep mode; when SWEN is
low, the receiver operates as a conventional single-conversion superhetero-
dyne receiver. This pin is internally pulled-up to VDDRF.
3
MICRF004/RF044
Micrel