AS3930-BQFT austriamicrosystems, AS3930-BQFT Datasheet - Page 12

• Manufacturer Part Number: AS3930-BQFT
• Description: IC RF PROGRAM RECEIVER 16-QFN
• Manufacturer: austriamicrosystems

Specifications of AS3930-BQFT

• Rf Type: Read / Write
• Frequency: 110kHz ~ 150kHz
• Features: RSSI Equipped
• Package / Case: 16-VFQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: AS3930-BQFTTR

AS3930
Data Sheet - D e t a i l e d D e s c r i p t i o n
AS3930 needs the following external components:
In case the internal RC-oscillator is used (no crystal oscillator is mounted), the pin XIN has to be connected to the supply, while pin XOUT should
stay floating. Application diagrams with and without crystal are shown in
8.2 Operating modes
8.2.1 Power Down Mode
In Power Down Mode AS3930 is completely switched off. The typical current consumption is 400 nA.
8.2.2 Listening Mode
In listening mode only the channel amplifier and the RTC are running. In this mode the system detects the presence of a carrier. In case the
carrier is detected the RSSI can be displayed.
Inside this mode it is possible to distinguish the following three sub modes:
8.2.2.1
The channel amplifier, capable to detect the presence of the carrier frequency, is active all the time.
8.2.2.2
The channel amplifier is active for one millisecond to be than switched-off for a certain time. The OFF-time is programmable see
Figure 11. ON/OFF Mode
For both sub modes it is possible to enable a further feature called Artificial Wake-up. If the Artificial Wakeup is enabled the AS3930 produces an
interrupt after a certain time regardless whether any activity is detected on the input. The period of the Artificial Wake-up is defined in the register
R8<2:0>. The user can distinguish between Artificial Wake-up and Wake-up based on the field detection (frequency or pattern detection) since
the Artificial Wake-up interrupt lasts only 128 μs. With this interrupt the microcontroller (μC) can get feedback on the surrounding environment
(e.g. read the false wakeup register, see relator register R13<7:0>) and/or take actions in order to change the setup.
8.2.3 Preamble Detection / Pattern Correlation
The chip can go in to this mode after detecting a LF carrier only if the data correlator function is enabled see
first for preamble frequency (constant frequency of Manchester clock defined according to bit-rate transmission) and then for data pattern.
If the pattern is matched the wake-up interrupt is displayed on the WAKE output and the chip goes in data receiving mode. If the pattern fails the
internal wake-up is terminated and no IRQ is produced.
www.austriamicrosystems.com/AS3930
Presence of
Power supply capacitor - CBAT – 100 nF
32.768 kHz crystal with its two pulling capacitors – XTAL and CL (it is possible to omit these components if the internal RC oscillator is used
instead of the crystal oscillator).
Input LC resonator.
Carrier
Channel
Standard Listening mode
ON/OFF mode (Low Power mode)
t0
t0 + 1ms
t0 + T
Revision 1.0
Figure 1
t0 + T + 1ms
and
Figure 2
t0 + 2T
R1<1>
. The correlator searches
R4<7:6>
Time
Time
12 - 33
.