ata5780 ATMEL Corporation, ata5780 Datasheet - Page 18

• Manufacturer Part Number: ata5780
• Description: Uhf Ask/fsk Receiver
• Manufacturer: ATMEL Corporation

4.5
4.5.1
4.5.2
4.5.2.1
18
Power Management
Atmel ATA5780 [Preliminary]
Introduction
Supplies
AVCC Supply Regulator
The IC has three power domains:
Each supply regulator has a corresponding reset. The reset thresholds ensure correct opera-
tion of the supplied circuits when the reset is de-asserted. This keeps inadvertent memory
content loss from happening without notice. The AVCC regulator has an additional threshold
above the reset to ensure that the analog circuits are working properly.
Figure 4-3.
The DVCC supply is enabled by a pin power-up. A pin power up happens when PWRON is set
to high or NPWRONx, are set to low for a time period longer than T
power-up source can be determined by reading the corresponding input ports.
The AVCC supply regulator provides the supply for the RF front end. It delivers a high output
current while retaining close control of voltage. Load transitions up to 3mA do not trigger the
AVCC low and reset indicators. This is necessary to allow timely activation of all front-end
circuits.
At supply voltages above 2.1V AVCC load transients of more than 8mA are allowed without
triggering the reset circuit.
• Vs - the unregulated battery voltage from the supply pin.
• DVCC - the regulated digital supply voltage.
• AVCC - the regulated RF-front-end supply.
Power Supply Management Overview
Rx/Tx
Front-End
AVCC
1.8 to 1.9V
RF-
AVCC_sup
AVCC_res
1.7 to 1.8
EN_AVCC
H
L
V
L
S
VS
1.9 to 5.5V
DSP
VMEM_sup
DVCC_sup
DVCC_res
1.2 to 1.3
LVLSH
Port B
EN_DVCC
SRC, FRC
EEPROM
AVR
DVCC
1.3 to 1.4V
V
S
H
L
L
O
R
C
P
T
power_on_REQ
9207BS–RKE–01/11
. The actual