FP115
Dual OPA Circuit with Precision Shunt Regulator
General Description
The FP115 incorporates dual operation amplifier and a precision shunt regulator (typ. 1.25V). The
main function of FP115 is CV control and OC sense for low power RCC circuits. The small package
SOT-23-5L is suitable for mini-size AC-DC power supply or adapter applications.
Features
 Fixed Reference Voltage: 1.25V
 Reference Voltage Precision: 2%
 Output Sink Current: 5mA
 Current Consumption: 2.4mA
 Output Inverting Voltage Deviation: OPA1: 3mV, OPA2: 1mV
 Wide Operation Voltage Range: 2.5V ~ 20V
 Package: SOT23-5L
Applications
 Charger
 Switching Power Supply
 AC Adapter
Function Block Diagram
VFB
VCC
2K
SHUNT
REGULATOR
OUT
GND
CS
This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice.
No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product.
Rev. 0.6
Website: http://www.feeling-tech.com.tw
1/9
FP115
Pin Descriptions
SOT23-5L
Name
Top View
1
GND
2
CS
3
4B915
OUT
5
4
VCC
No. I / O
Description
OUT
1
I
Open Emitter
GND
2
P
Ground
CS
3
I
Current Sense Input
VFB
4
I
Voltage Feedback Sense Input
VCC
5
P
IC Power Supply
VFB
IC Date Code Identification
SOT23-5L
Lot Number: Wafer lot number’s last two digits
For Example: 132386TB  86
Year: Production year’s last digit
Mass Production Version: Mass production mask version
Part Number Code: Part number identification code for this product. It should be always “4”.
This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice.
No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product.
Rev. 0.6
Website: http://www.feeling-tech.com.tw
2/9
FP115
Ordering Information
Part Number
Operating Temperature
Package
MOQ
Description
-20°C ~ +85°C
SOT23-5L
2500EA
Tape & Reel
FP115KR-LF
Absolute Maximum Ratings
Parameter
Symbol
Conditions
Min.
Typ.
Max.
Unit
Supply Voltage
Vcc
2.5
20
V
Input Voltage On Other Pins
Vi
-0.3
Vcc
V
250
mW
+125
°C
+150
°C
+250
°C / W
Power Dissipation
TA=25°C
Storage Temperature
Maximum Junction Temperature
-40
TJ
Lead Temperature (soldering, 10 sec)
IR Re-flow Soldering Curve
This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice.
No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product.
Rev. 0.6
Website: http://www.feeling-tech.com.tw
3/9
FP115
Recommended Operating Conditions
Parameter
Supply Voltage
Symbol
Conditions
Vcc
Operating Temperature
Min.
Typ.
Max.
Unit
2.5
20
V
-20
+85
°C
DC Electrical Characteristics (Vcc=5V, TA= 25°C, unless otherwise noted)
Parameter
Symbol
Conditions
Min.
Typ.
Max.
Unit
1.225
1.25
1.275
V
30
150
nA
OPA1 Section
Output Inverting Voltage
VFB
VCS=0V, RL=4.3K, VCC=5K
Input Bisa Current
IB1
VCS=0V, RL=4.3K
PSRR
Output Sink Current
Output Inverting Voltage Deviation
PSRR1 VCS=0V, RL=4.3K
VFB=1.35V, VCS=0V,
IO1
VOUT=1.5V
Vcs=0V, RL=4.3V,
△VFB
VCC=2.5V~5V
50
dB
5
mA
Output Inverting Voltage
Temperature Coefficient
3
mV
±100
ppm / ℃
OPA2 section
Output Inverting Voltage
VCS
VFB=0V, RL=4.3K, VCC=5V
Input Bias Current
IB2
VFB=0V, RL=4.3K
PSRR
Output Sink Current
Output Inverting Voltage Deviation
PSRR2 VFB=0V, RL=4.3K
VCS=0.17V, VFB=0V,
IO2
VOUT=1.5V
VFB=0V, RL =4.3K,
△VCS
VCC=2.5~5V
Output Inverting Voltage
Temperature Coefficient
150
156
162
mV
30
150
nA
50
dB
5
mA
1
mV
±100
ppm/℃
Total Device
Current Consumption
ICC
VFB=0V, VCS=0V, RL=∞
2.4
3.4
mA
This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice.
No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product.
Rev. 0.6
Website: http://www.feeling-tech.com.tw
4/9
FP115
Typical Operating Characteristics
(TA=25°C, unless otherwise noted)
This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice.
No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product.
Rev. 0.6
Website: http://www.feeling-tech.com.tw
5/9
FP115
Function Description
Internal Reference Regulator
The FP115 includes a 1.25V high precision shut regulator to reduce application circuit external
part number. This 1.25V reference voltage is divided down by resistor string to 156mV then connects
to OPA1 and OPA2’s non-inverting input for comparison. Applications with VCC voltage higher than 20V
are not suitable for this chip as an internal 2KΩ resistor which connected between Vcc and 1.25V
reference will draw too much current and increase power loss.
VCC
5
2K
1.25V
156mV
2
GND
Figure 5 1.25V Reference Regulator With Resistor Divider
For example:
If VCC is 6V, the power loss of the 2KΩ resistor is (6-1.25)2/2KΩ=11.3mW. When VCC is 12V, the
power loss of the 2KΩ resistor is (12-1.25)2/2KΩ=57.8mW.
This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice.
No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product.
Rev. 0.6
Website: http://www.feeling-tech.com.tw
6/9
FP115
Operation Amplifier 1 and Operation Amplifier 2
FP115 includes two operation amplifiers. Their outputs are tied together to implement wired-NOR
function. When the inverting input voltage of OPA is lower than non-inverting reference voltage, the
output transistor is turn-off; otherwise the output transistor is turn-on. The output total sink current
ability is near 10mA
When apply FP115 in an AC-DC converter circuit, connect FP115’s output (pin1) to a
photo-coupler. The output will drive photo diode turning-on or off depending on the FB and CS pin
voltage to adjust AC-DC converter’s output voltage.
In general, OPA1 is used for voltage feedback and OPA2 is used for over current feedback.
Please check FP115 application note for detail design reference circuits.
Voltage feedback equation:
R2 

VOUT  1 
  1.25 V
R1 

Current feedback equation:
156mV  Io  Rs
This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice.
No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product.
Rev. 0.6
Website: http://www.feeling-tech.com.tw
7/9
FP115
Application Circuit
1
1
M1
N
4 -
RV1
07D471K
1
BD1
DB105G
1
18uH
3
F1
+
222 50V
5
L2
VB
C1
4.7uF 400V
C2
4.7uF 400V
+
VOUT
22uH
R3
100K
C3
6
4
102 1KV
0.1 1W
M2
C7
T1
L1
+ 2
SB260
D3
+
C8
1000uF 10V
+
C9
220uF/16V
3
L
2
D1
PS1010
VB
ST
U2
OUT
R2
4.3M
R5
1.1K
1
2
C10
104
CS 3
ZD2
8.1V 1/2W
OUT
CS
C4
2200pF
VFB
R6 82
Q1
2N60B
0.22
R19
Q2
2N3904
R7
0.22
220
VOUT
R10
R13
C11
300K
VOUT
220
R11
39K 1%
4
C5
0.1uF
RTN
R16
4.7K
3
2
OUT
C12
CS
OUT
M4
1
RTN
103
PC817
Figure 6
VOUT
R20
4.7K
1
LED1
R12
330
1
0.22u
R14
82K
R15
10
M3
OUT
FB
U1
150
750
R18
2200pF
VB
1N4148
FB
1.8K
R8
2.2
R9
4
RTN
R4
ZD1
9V 1/2W
D2
5
FP115
R17
C6
VCC
GND
3.5W RCC Adapter Application Circuit
This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice.
No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product.
Rev. 0.6
Website: http://www.feeling-tech.com.tw
8/9
FP115
Package Outline
SOT23-5L
UNIT: mm
Symbols
Min. (mm)
Max.(mm)
A
1.050
1.350
A1
0.050
0.150
A2
1.000
1.200
b
0.250
0.500
c
0.080
0.200
D
2.700
3.000
E
2.600
3.000
E1
1.500
1.700
e
0.950 BSC
e1
1.900 BSC
L
0.300
0.550
L1
0.600 REF
L2
0.250 BSC
θ°
0°
10°
θ1°
3°
7°
θ2°
6°
10°
Note:
1. Package dimensions are in compliance with JEDEC outline: MO-178 AA.
2. Dimension “D” does not include molding flash, protrusions or gate burrs.
3. Dimension “E1” does not include inter-lead flash or protrusions.
This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice.
No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product.
Rev. 0.6
Website: http://www.feeling-tech.com.tw
9/9