ADP1610 Analog Devices, ADP1610 Datasheet - Page 15

• Manufacturer Part Number: ADP1610
• Description: 1.2 MHz DC-DC Step-Up Switching Converter
• Manufacturer: Analog Devices

APPLICATION CIRCUITS
The circuit in Figure 27 shows the ADP1610 in a step-up confi-
guration that can be used to generate a 10 V regulator with the
following specifications: V
I
The output is set to the desired voltage using Equation 1.
To change the compensation network, see Equation 17 and
Equation 18.
DC-TO-DC STEP-UP SWITCHING CONVERTER
WITH TRUE SHUTDOWN
Some battery-powered applications require very low standby
current. The ADP1610 typically consumes 10 nA from the
input, which makes it suitable for these applications. However,
the output is connected to the input through the inductor and
the rectifying diode, allowing load current draw from the input
while shut down. The circuit in Figure 28 enables the ADP1610
to achieve output load disconnect at shutdown. To shut down
the ADP1610 and disconnect the output from the input, drive
the SD pin below 0.4 V.
10kΩ
OUT
3.3V
R3
3.3V
10µF
C
Q1
≤ 400 mA.
IN
Q1
B
A
OFF
FDC6331
Figure 28. Step-Up Regulator with True Shutdown
22nF
C
10µF
SS
C
Figure 27. 3.3 V to 10 V Step-Up Regulator
IN
ON
6
3
7
8
22nF
C
IN
SD
RT
SS
SS
ADP1610
IN
= 2.5 V to 5.5 V, V
4.7µH
GND
6
3
7
8
L
4
SD
RT
SS
IN
COMP
ADP1610
SW
FB
4.7µH
GND
L
4
5
1
2
COMP
R
220kΩ
SW
FB
C
150pF
COMP
71.3kΩ
COMP
D1
OUT
10kΩ
5
1
2
R1
R2
= 10 V, and
R
220kΩ
C
150pF
COMP
71.3kΩ
COMP
D1
10kΩ
C
10µF
R1
R2
10V
OUT
Rev. A | Page 15 of 20
C
10mF
10V
OUT
TFT LCD BIAS SUPPLY
Figure 29 shows a power supply circuit for TFT LCD module
applications. This circuit has +10 V, −5 V, and +22 V outputs.
The +10 V is generated in the step-up configuration. The −5 V
and +22 V are generated by the charge-pump circuit. During
the step-up operation, the SW node switches between 10 V and
ground (neglecting forward drop of the diode and on resistance
of the switch). When the SW node is high, C5 charges up to 10 V.
C5 holds its charge and forward-biases D8 to charge C6 to −10 V.
The Zener diode (D9) clamps and regulates the output to −5 V.
The VGH output is generated in a similar manner by the charge-
pump capacitors, C1, C2, and C4. The output voltage is tripled
and regulated down to 22 V by the Zener diode, D5.
3.3V
10µF
C
IN
22nF
C
BZT52C5VIS
SS
VGL
–5V
ON
6
3
7
8
D9
IN
SD
RT
SS
Figure 29. TFT LCD Bias Supply
ADP1610
200Ω
R4
10µF
4.7mH
C6
GND
L
4
BAV99
COMP
D8
D7
SW
FB
10nF
C5
5
1
2
10nF
10nF
R
220kΩ
C
150pF
C4
C1
COMP
COMP
D1
71.3kW
BAV99
BAV99
10kΩ
D5
D4
D3
D2
R1
R2
10µF
C3
ADP1610
C2
1µF
200Ω
C
10µF
R3
10V
OUT
BZT52C22
D5
VGH
22V