Rainbow Electronics ATA5812 - Manual (Page 26)

26
ATA5811/ATA5812 [Preliminary]
4689B–RKE–04/04
Power Supply
Figure 21. Power Supply
The supply voltage range of the ATA5811/ATA5812 is 2.4 V to 3.6 V or 4.4 V to 6.6 V.
Pin VS1 is the supply voltage input for the range 2.4 V to 3.6 V and is used in battery
applications using a single lithium 3 V cell. Pin VS2 is the voltage input for the range
4.4 V to 6.6 V (2 Battery Application and Car Applications) in this case the voltage regu-
lator V_REG1 regulates VS1 to typically 3.25 V. If the voltage regulator is active a
blocking capacitor of 2.2 µF has to be connected to VS1.
Pin VAUX is an input for an additional auxiliary voltage supply and can be connected
e.g., to an inductive supply (see Figure 26 on page 32). This input can only be used
together with a rectifier or as in the application of Figure 5 on page 7 and must otherwise
be left open.
Pin VSINT is the voltage input for the Microcontoller_Interface and must be connected
to the power supply of the microcontroller. The voltage range of V
VSINT
is 2.4 V to 5.25 V
(see Figure 25 on page 31 and Figure 26 on page 32).
V_REG1
3.25 V typ.
IN OUT
V_REG2
3.25 V typ.
IN
S
R
≥ 1
AVCC_EN
VAUX
T1
PWR_ON
DVCC_OK
OFFCMD
Q
VS2
VS1
EN
VSOUT_EN
VS1+
0.55V
typ.
and
AVCC
DVCC
VSOUT
(Control Register 3)
(Control Register 1)
OUT
EN
P_On_Aux
(Status Register)
(Command via SPI)
DVCC_OK
(to XTO and
Reset Logic )
Low_Batt
(Status Register
and Reset Logic)
SW_AVCC
SW_DVCC
SW_VSOUT
S R Q
0 0 no change
0 1 0
1 0 1
1 1 1
FF1
VSINT
V_Monitor
(1.5 V typ.)
V_Monitor
(2.3 V/
2.38 V typ.)
T5
VSOUT_OK
(to XTO and
Reset Logic)
≥
1