L2800G-S08-T [UTC]
SWITCHING REGULATOR CONTROLLER(LOW VOLTAGE); 开关稳压器控制器(低电压)型号: | L2800G-S08-T |
厂家: | Unisonic Technologies |
描述: | SWITCHING REGULATOR CONTROLLER(LOW VOLTAGE) |
文件: | 总7页 (文件大小:248K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
UNISONIC TECHNOLOGIES CO., LTD
L2800
LINEAR INTEGRATED CIRCUIT
SWITCHING REGULATOR
CONTROLLER(LOW VOLTAGE)
SOP-8
DESCRIPTION
The UTC L2800 which is incorporating a soft start function and
short circuit detection function is a single-channel switching
regulator control IC and is made for low voltage applications.
Because the device has a low minimum operating voltage of 1.8V,
so it is ideal for the power supply of battery-operated electronic
equipment.
TSSOP-8
FEATURES
*Wide supply voltage operating range: 1.8V~15V
*Low current consumption: Typically 5.5mA in operation,1μA or
less in stand-by
*High speed operation is possible: Maximum 1MHz
*The error amplifier gain is set inside the IC, so peripheral
components are minimized.
*Incorporates a soft start circuit.
*Incorporates a timer-latch type short circuit detection circuit (SCP).
*Totem-pole type output with adjustable on/off current (for NPN
transistors)
*Incorporates a stand-by function.
ORDERING INFORMATION
Ordering Number
Package
Packing
Lead Free
Halogen Free
L2800G-S08-T
L2800G-S08-R
L2800G-P08-T
L2800G-P08-R
L2800L-S08-T
L2800L-S08-R
L2800L-P08-T
L2800L-P08-R
SOP-8
SOP-8
Tube
Tape Reel
Tube
TSSOP-8
TSSOP-8
Tape Reel
www.unisonic.com.tw
1 of 7
Copyright © 2011 Unisonic Technologies Co., Ltd
QW-R103-030,B
L2800
LINEAR INTEGRATED CIRCUIT
PIN CONFIGURATION
PIN DESCRIPTION
PIN NO.
SYMBOL
-IN
I/O
DESCRIPTION
1
2
3
4
5
6
7
8
I
-
Error amplifier inverting input pin
SCP
Soft start and SCP setting capacitor connection pin
Power supply pin
VCC
-
BR/CTL
OUT
I
Output current setting and control pin
Totem-pole type output pin
O
-
GND
OSC
FB
Ground pin
-
Capacitor and resistor connection pin for setting the oscillation frequency
Error amplifier output pin
O
BLOCK DIAGRAM
UNISONIC TECHNOLOGIES CO., LTD
2 of 7
QW-R103-030,B
www.unisonic.com.tw
L2800
LINEAR INTEGRATED CIRCUIT
ABSOLUTE MAXIMUM RATINGS (TA=25℃)
PARAMETER
SYMBOL
VCC
RATINGS
16
UNIT
V
Power Supply Voltage
Output Source Current
Output Sink Current
+
IO
-50
mA
mA
-
IO
50
SOP-8
570
Power Dissipation (Note2)
PD
mW
TSSOP-8
580
Storage Temperature
Operating Temperature
TSTG
TOPR
-55 ~ +125
-30 ~ +85
°C
°C
Notes: 1. Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.
2. When mounted on a 10cm square double-sided epoxy board.
RECOMMENDED OPERATING CONDITIONS (TA=25°C)
PARAMETER
SYMBOL
VCC
MIN
1.8
TYP
MAX
15
UNIT
V
Power Supply Voltage
Error Amplifier Input Voltage
BR/CTL Pin Input Voltage
Output Source Current
Output Sink Current
VI
-0.2
-0.2
-40
1.0
V
VBR
VCC
V
+
IO
mA
mA
μF
μF
Ω
kΩ
pF
kHz
°C
-
IO
40
SCP Pin Capacitance
CPE
CP
0.1
0.1
Phase Compensation Capacitance
Output Current Setting Resistance
Timing Resistance
RB
150
1.0
100
10
390
3.0
5000
10.0
RT
Timing Capacitance
CT
270
500
+25
10000
1000
+85
Oscillation Frequency
fOSC
TOPR
Operating Temperature
-30
UNISONIC TECHNOLOGIES CO., LTD
3 of 7
QW-R103-030,B
www.unisonic.com.tw
L2800
LINEAR INTEGRATED CIRCUIT
ELECTRICAL CHARACTERISTICS (TA=25°C, VCC=+2V)
PARAMETER SYMBOL TEST CONDITIONS
CIRCUIT TO PREVENT MALFUNCITION AT LOW INPUT OLTAGE (U.V.L.O)
MIN TYP MAX UNIT
Reset Voltage
VR
0.9
1.5
V
V
Threshold Voltage
VTH
1.1
1.3
Soft Start
Charging Current
ICS
VSCP=0V
VSCP=0V
-1.5 -1.0 -0.7
0.7 0.8 0.9
μA
V
Voltage at soft start completion
Short Circuit Detection(S.C.P.)
Charging Current
VTS
ICPC
-1.5 -1.0 -0.7
0.7 0.8 0.9
μA
V
Threshold Voltage
VTPC
SAWTOOTH WAVE OSCILLATOR(OSC)
Oscillation Frequency
Frequency Input Stability
Frequency Variation With Temperature
ERROR AMPLIFIER
Input Threshold Voltage
VT Input Stability
fOSC
fDV
RT=3.0kΩ, CT=270pF
VCC=2V ~ 15V
400 500 600 kHz
2
5
10
%
%
fDT
TA=-30°C ~ +85°C
VT
VTDV
VTDT
IB
VFB=450mV
480 500 520 mV
VCC=2V ~ 15V
TA= -30°C ~ +85°C
VIN=0V
5
1
20
mV
%
VT Variation With Temperature
Input Bias Current
-1.0 -0.2
1.0
μA
Voltage Gain
Av
70
100 145 V/V
Frequency Bandwidth
BW
AV=0dB
6
MHz
V
+
VOM
0.78 0.87
0.05 0.2
Maximum Output Voltage Range
-
VOM
V
+
Output Source Current
IOM
-40
40
-24
μA
μA
VFB=0.45V
-
Output Sink Current
IOM
24
65
IDLE PERIOD ADJUSTMENT SECTION
Maximum Duty Cycle
tDUTY
RT=3.0kΩ, CT=270pF, VFB=0.8V
75
85
%
OUTPUT SECTION
VOH1
VOH2
VOL1
VOL2
RB=390Ω, Io=-15mA
RB=750Ω, VCC=1.8V, Io= -10mA
RB=390Ω, Io=15mA
RB=750Ω, VCC=1.8V, Io=10mA
RB=390Ω, Vo=0.9V
RB=390Ω, Vo=0.3V
1.0
0.8
1.2
1.0
0.1
0.1
-30
60
V
V
Output Voltage
0.2
0.2
-20
V
V
+
Output Source Current
Output Sink Current
Pull Down Resistance
IO
mA
mA
kΩ
-
IO
30
20
RO
30
40
OUTPUT CURRENT SETTING SECTION/CONTROL SECTION
Pin Voltage
VBR
IOFF
ION
RB=390Ω
0.2
-20
0.3
0.4
0
V
Input Off Condition
Input On Condition
Pin Current Range
ENTIRE DEVICE
Stand-by Current
Average Supply Current
μA
μA
-45
IBR
-1.8
-0.1 mA
ICCS
ICC
BR/CTL pin open or VCC
1
μA
mA
RB=390Ω
5.5
9.3
UNISONIC TECHNOLOGIES CO., LTD
4 of 7
QW-R103-030,B
www.unisonic.com.tw
L2800
LINEAR INTEGRATED CIRCUIT
DIAGRAM
HOW TO SET THE TIME CONSTANT FOR SHORT CIRCUIT DETECTION AND SOFT
START
1. SHORT CIRCUIT PROTECTION
Te error amplifier output (FB pin) is fixed at VOM+ and capacitor CPE starts charging i the switching regulator
output suddenly drops due to load effect. The output pin is set low and the SCP pin stays low when the voltage at
the SCP pin reaches approximately 0.8V.
As the protection circuit operates, by resetting the power supply the circuit will be restored.
•Short circuit detection time
t
PE[S]≒0.8*CPE[μF]
2. SOFT START
Once power on, the capacitor CPE which is connected to the SCP pin starts charging.The soft start setting
voltage is compared by the PWM comparator as the voltage’s proportion at the SCP pin with the sawtooth
waveform. The comparison controls the OUT pin’s ON duty,which is causing the soft start operation. During the
time for completion of soft start operation, the SCP pin’s voltage stays low, but the soft start setting voltage stays
high, and the circuit then enters the output short circuit detection wait state.
Soft start time (until the output ON duty reaches approximately 50%)
ts[S]≒0.35*CPE[μF]
UNISONIC TECHNOLOGIES CO., LTD
5 of 7
QW-R103-030,B
www.unisonic.com.tw
L2800
LINEAR INTEGRATED CIRCUIT
APPLICATION EXAMPLE
22μH
18kΩ
VO
5V
1
8
-IN
FB
VIN
3V
0.1μF
7
2
3
4
OSC
SCP
10μF
6
GND
Vcc
33μF
2kΩ
5
OUT
BR/CTL
0.1μF
390Ω
270pF
3kΩ
CTL
UNISONIC TECHNOLOGIES CO., LTD
6 of 7
QW-R103-030,B
www.unisonic.com.tw
L2800
LINEAR INTEGRATED CIRCUIT
TYPICAL CHARACTERISTICS
UTC assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or
other parameters) listed in products specifications of any and all UTC products described or contained
herein. UTC products are not designed for use in life support appliances, devices or systems where
malfunction of these products can be reasonably expected to result in personal injury. Reproduction in
whole or in part is prohibited without the prior written consent of the copyright owner. The information
presented in this document does not form part of any quotation or contract, is believed to be accurate
and reliable and may be changed without notice.
UNISONIC TECHNOLOGIES CO., LTD
7 of 7
QW-R103-030,B
www.unisonic.com.tw
相关型号:
©2020 ICPDF网 联系我们和版权申明