AS1301A-BWLT austriamicrosystems, AS1301A-BWLT Datasheet - Page 10

• Manufacturer Part Number: AS1301A-BWLT
• Description: IC BOOST/SW CAP 5V 50MA 8WLCSP
• Manufacturer: austriamicrosystems
• Type: Step-Up (Boost), Switched Capacitor (Charge Pump)r

Specifications of AS1301A-BWLT

• Internal Switch(s): Yes
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: 5V
• Current - Output: 50mA
• Frequency - Switching: 1MHz
• Voltage - Input: 2.7 ~ 5.25 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Other names: AS1301A-BWLTTR

AS1301
Datasheet - D e t a i l e d D e s c r i p t i o n
8.2 Switch Configuration
The AS1301 has nine built-in power switches in the shape of two coupled H-bridge topologies. The system features 1:2 and 2:3 operation modes
as well as a 1:1 operation where the input is directly connected to the output. This feedthrough mode is suitable for input voltages higher than the
output voltage.
In 2:3 operation mode two flying capacitors are placed in series and each capacitor is charged to a half of the input voltage. In pumping phase
the flying capacitors are placed in parallel. The bottom-plates of the parallel flying capacitors C
voltage so that the voltage at the top-plates of the flying capacitors is boosted to a voltage equal to V
plates of the capacitors to the output, the output voltage in 2:3 mode can be up to one and a half of V
5V, the regulation loop adapts the power transistor’s current drive capability to drop some voltage. The 2:3 operation mode runs in single-phase
operation only.
Figure 27. 2:3 Operating Mode
In 1:2 operation mode just one of both flying capacitors is placed in series to the input voltage, and therefore charged to the input voltage. During
pumping phase the input voltage is connected to the bottom-plate of the discharged flying capacitor C
capacitor is now boosted to 2V
V
capacitor this mode features dual-phase operation.
Figure 28. 1:2 Operating Mode
www.austriamicrosystems.com/DC-DC_Step-Up/AS1301
BATT
. If the top-plate voltage is higher than 5V the regulation loop limits the charge transfer to the output. In collaboration with the second flying
VBATT
VBATT
Charging Phase
BATT
SW2
SW2
Charging Phase
C
C
. By connecting the top-plate of the capacitor to the output, the output can be charged to twice the voltage of
FLY1
FLY1
SW4
SW4
SW1
SW1
SW3
SW3
C
C
FLY2
FLY2
VOUT
VOUT
Revision 1.05
VBATT
VBATT
FLY1
Pumping Phase
and C
BATT
BATT
FLY
Pumping Phase
SW2
. The voltage at the top-plate of the
SW2
FLY2
. If the top-plate voltage is higher than
+ V
C
C
FLY1
FLY1
BATT
are then connected to the input
/2. By connecting the top-
SW4
SW4
SW1
SW1
SW3
SW3
C
C
FLY2
FLY2
VOUT
VOUT
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