AIMTRON AT1780M-GRE

AT1780
Preliminary Product Information
640kHz/1.2MHz,Low-Noise Step-Up
Current-Mode PWM Controller
Features
General Description
• 1.6A,0.21Ω,14V Power MOSFET
• Operating input voltage:+2.6V to +5.5V
• Adjustable Output from VIN to 12V
• 640kHz /1.2MHz pin selectable switching
Frequency
• 0.1μA shutdown Current
• Built-in Soft-Start function
• Small 8-Pin MSOP Package
The AT1780 is a current-mode step-up DC/DC
converter with a 1.6A, 0.21Ω power MOSFET.
The soft-start function is programmed with an
external capacitor, which sets the input current
ramp rate. It is ideal for generating bias voltages
for LCD panels. Pin selectable frequency 640KHz
or 1.2MHz operation results in a low noise output
that is easy to filter and faster loop performance.
An external compensation pin provides the user
flexibility in determining loop dynamics, allowing
the use of small, low equivalent series resistance
(ESR) ceramic output capacitors.
Applications
• LCD Displays
• Digital Cameras
• Portable Applications
• Hand-Held Devices
*Protected by U.S. Patent # 6,791,368
Block Diagram
COMP
VIN
SHDN
Reference
1.24V
Power
ON/OFF
SOFTSTART
BIAS
4uA
SS
Enable
+
Error
Amplifier
FB
Comparator
gm
1.24V
LX
-
+
R
+
Clock
Q
N
S
GND
FSLC
Oscillator
Ramp
Generator
+
+
CURRENT
SENSE
Aimtron reserves the right without notice to change this circuitry and specifications.
7F, No.9, PARK AVENUE II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 Fax: 886-3-563-0879
WWW: http://www.aimtron.com.tw
3/24/06 REV 1.1
Email: service@aimtron.com.tw
1
AT1780
Preliminary Product Information
640kHz/1.2MHz,Low-Noise Step-Up
Current-Mode PWM Controller
Pin Configuration
8
7
6
5
1780
1
2
3
4
Ordering Information
Part number
AT1780M_GRE
Package
MSOP8,Green
Marking
1780,data code with one bottom line
*For more marking information, contact our sales representative directly
Pin Description
Pin No.
Symbol
I/O
1
2
3
4
5
6
7
8
COMP
FB
/SHDN
GND
LX
VIN
FSLC
SS
I
I
O
I
—
Description
Compensation network connection.
Output voltage feedback input
Shutdown control input, active low
Ground
Switch Pin.
Power supply pin.
Frequency select input. Ground=640KHz, VIN=1.2MHz
Soft-Start control pin.
7F, No.9, PARK AVENUE II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 Fax: 886-3-563-0879
WWW: http://www.aimtron.com.tw
3/24/06 REV 1.1
Email: service@aimtron.com.tw
2
AT1780
Preliminary Product Information
640kHz/1.2MHz,Low-Noise Step-Up
Current-Mode PWM Controller
Absolute Maximum Ratings
Parameter
Condition
LX to GND
IN, /SHDN, FREG, FB to GND
SS, COMP to GND
RMS LX pin current
Continuous power dissipation
Operating temperature
Junction temperature
Storage temperature
Lead temperature
—
—
—
—
8pin μMAX(TA=+70℃)
—
—
—
—
Rated Value
Min.
Max.
-0.3
+14
-0.3
+6
-0.3
VIN+0.3
—
1.2
—
330
-30
+85
—
+150
-40
+150
—
+300
Unit
V
V
V
A
mW
0
C
0
C
0
C
0
C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are
stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the
operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended
periods may affect device reliability.
Recommended Operating Conditions
(Ta=+250C)
Parameter
Power supply voltage
SS pin capacitance
Phase compensation capacitance
Phase compensation capacitance
Phase compensation resistance
Oscillation frequency
Operating temperature
Symbol
VIN
CPE
CCOMP1
CCOMP2
RCOMP
fOSC1
fOSC2
TOP
Values
Min.
2.6
----540
1000
-30
Typ.
-0.033
470
18
30
640
1220
+25
Unit
Max.
5.5
----740
1500
+85
V
μF
pF
pF
KΩ
kHz
kHz
°C
7F, No.9, PARK AVENUE II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 Fax: 886-3-563-0879
WWW: http://www.aimtron.com.tw
3/24/06 REV 1.1
Email: service@aimtron.com.tw
3
AT1780
Preliminary Product Information
640kHz/1.2MHz,Low-Noise Step-Up
Current-Mode PWM Controller
Electrical Characteristics
(VIN = SHDN = 3V, FREQ = GND, TA =0℃ to +85℃, unless otherwise noted. Typical values are at TA = +25℃.)
Parameter
Symbol
Condition
Values
Unit
Min. Typ. Max.
Input Supply Range
VIN
VIN
Undervoltage
UVLO
Lockout
Entire device
Quiescent Current
Error amplifier
Sawtooth wave
oscillator (OSC)
N-CHANNEL
SWITCH
SOFT-START
CONTROL INPUTS
IIN
Shutdown Supply
Current
IIN
Feedback Voltage
VFB
FB Input Bias Current
IFB
Feedback-Voltage Line
Regulation
Transconductance
Voltage Gain
gm
Av
Frequency
fosc
Maximum Duty Cycle
DC
Current Limit
ILIM
On-Resistance
RON
Leakage Current
Current-Sense
Transresistance
Reset Switch
Resistance
Charge Current
ILXOFF
VIL
Input High Voltage
VIH
IFSLC
ISHDN
2.1
Level to produce
1.222
VCOMP = 1.24V
VFB = 1.25V
Level to produce
VCOMP = 1.24V,
2.6V < VIN < 5.5V
ΔI = 5µA
-FSLC = GND
540
FSLC = IN
1050
FSLC = GND
79
FSLC = IN
VFB = 1V, duty cycle =
1.2
65%
ILX = 1.2A
VLX = 12V
0.3
VSS = 1.2V
/SHDN, FREQ;
VIN = 2.6V to 5.5V
/SHDN, FREQ;
VIN = 2.6V to 5.5V
SHDN, FREQ
2.3
5.5
V
2.5
V
0.218 0.35
/SHDN = GND
RCS
Input Low Voltage
Hysteresis
FSLC Pull-Down
Current
/SHDN Input Current
2.6
VIN rising, typical
hysteresis is 40mV,LX
remains off below this
level
VFB = 1.3V, not
switching
VFB = 1.0V, switching
1.5
2.045
5
0.1
10
1.24 1.258
0
40
mA
μA
V
nA
0.05 0.15 %/V
μmhos
140
500
V/V
640 740
kHz
1200 1350
91.3 92
%
82.1
1.6
2.3
A
0.21
0.5
0.01
20
Ω
μA
0.45 0.65 V/A
4
100
Ω
7
μA
0.4
V
1.6
V
100
mV
1.5
5
9
μA
0.001
1
μA
7F, No.9, PARK AVENUE II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 Fax: 886-3-563-0879
WWW: http://www.aimtron.com.tw
3/24/06 REV 1.1
Email: service@aimtron.com.tw
4
AT1780
Preliminary Product Information
640kHz/1.2MHz,Low-Noise Step-Up
Current-Mode PWM Controller
Typical Characteristics
(VIN = 3.3V, FREQ = GND, TA=25℃, unless otherwise noted.)
Efficiency vs. Output current
Efficiency vs. Output current
90
90
85
85
Efficiency Eff (%)
Efficiency Eff (%)
AT1780
95
AT1780
95
80
75
80
70
75
70
Vin=3.3V
Vout=10V
fosc=640kHz
L=10uH
65
1
10
100
Output current Iout (mA)
Vin=3.3V
Vout=10V
fosc=1.2MHz
L=4.7uH
65
1000
1
10
100
Output current Iout (mA)
Output voltage vs. Output current
Output voltage vs. Output current
AT1780
10.05
Output voltage Vout (V)
10.05
10.00
9.95
9.90
9.85
9.80
9.75
Vin=3.3V
Vout=10V
fosc=640kHz
L=10uH
9.70
9.65
0
40
80
120
160
200
Output current Iout (mA)
CH1:Output voltage,100mV/div/AC
CH4:Output current,100mA/div/DC
Vout=10V,fosc=640kHz,L=10uH
R1=100k,C1=470PF,C2=18PF
240
AT1780
10.10
10.10
Output voltage Vout (V)
1000
10.00
9.95
9.90
9.85
9.80
9.75
Vin=3.3V
Vout=10V
fosc=1.2MHz
L=4.7uH
9.70
9.65
0
40
80
120
160
200
Output current Iout (mA)
240
CH1:Output voltage,100mV/div/AC
CH4:Output current,100mA/div/DC
Vout=10V,fosc=1.2MHz,L=4.7uH
R1=100k,C1=470PF,C2=18PF
7F, No.9, PARK AVENUE II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 Fax: 886-3-563-0879
WWW: http://www.aimtron.com.tw
3/24/06 REV 1.1
Email: service@aimtron.com.tw
5
AT1780
Preliminary Product Information
640kHz/1.2MHz,Low-Noise Step-Up
Current-Mode PWM Controller
Typical Characteristics (continuted)
CH1:LX voltage,5V/div/DC
CH4:Inductor current,500mA/div/DC
Vout=10V,fosc=640kHz,L=10uH
CH1:LX voltage,5V/div/DC
CH4:Inductor current,500mA/div/DC
Vout=10V,fosc=1.2MHz,L=4.7uH
CH1:LX voltage,5V/div/DC
CH2:Vin and /SHDN voltage,2V/div/DC
CH3:SS voltage,2V/div/DC
CH4:Iin current,500mA/div/DC
Vout=10V,Iout=100mA,
fosc=640kHz,L=10uH
CH1:LX voltage,5V/div/DC
CH2:Vin and /SHDN voltage,2V/div/DC
CH1:SS voltage,2V/div/DC
CH4:Iin current,500mA/div/DC
Vout=10V,Iout=100mA,
fosc=1.2MHz,L=4.7uH
7F, No.9, PARK AVENUE II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 Fax: 886-3-563-0879
WWW: http://www.aimtron.com.tw
3/24/06 REV 1.1
Email: service@aimtron.com.tw
6
AT1780
Preliminary Product Information
640kHz/1.2MHz,Low-Noise Step-Up
Current-Mode PWM Controller
Typical Application Circuit
Vin
2.6V to 5.5V
Vout
D1
L1
Cin
Cout
Aimtron
6
3
C1
0.1UF
1
4
LX
/SHDN
FB
COMP
FLSC
5
2
7
R2
8
SS
Rcomp
Cout
AT1780
VIN
GND
R1
Css
Ccomp1
Ccomp
Figure 1.Typical application circuit
Vin
3.0V to 3.6V
CRS01
4.7UH
VAA
10V/150mA
22UF
10UF
6
3
C1
0.1UF
1
4
Aimtron
LX
/SHDN
FB
COMP
FLSC
SS
5
47K
2
D2
7
0.1UF
8
D5
0.1UF
30K
18PF
10UF
AT1780
VIN
GND
332K
0.033UF
D3
1UF
D4
VGH
30V/5mA
1UF
470PF
0.1UF
D7
D6
VGL
-10V/10mA
4.7UF
Figure 2.TFT panel power supply application circuit
7F, No.9, PARK AVENUE II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 Fax: 886-3-563-0879
WWW: http://www.aimtron.com.tw
3/24/06 REV 1.1
Email: service@aimtron.com.tw
7
AT1780
Preliminary Product Information
640kHz/1.2MHz,Low-Noise Step-Up
Current-Mode PWM Controller
Small Outline
8-pin Plastic µMAX
D
S
8
7
6
5
E
1
2
3
5
5
7
8
4
3
2
1
H
4
A
α
A1
C
B
e
SYMBOL
A
A1
B
C
D
e
E
H
L
α
S
INCHES
MIN
MAX
0.037
0.043
0.002
0.006
0.010
0.014
0.005
0.007
0.116
0.120
0.0256 BSC
0.116
0.120
0.188
0.198
0.016
0.026
0°
6°
0.207 BSC
L
MILLIMETERS
MIN
MAX
0.94
1.10
0.05
0.15
0.25
0.36
0.13
0.18
2.95
3.05
0.65 BSC
2.95
3.05
4.78
5.03
0.41
0.66
0°
6°
0.525 BSC
NOTES
-
7F, No.9, PARK AVENUE II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 Fax: 886-3-563-0879
WWW: http://www.aimtron.com.tw
3/24/06 REV 1.1
Email: service@aimtron.com.tw
8
AT1780
Preliminary Product Information
640kHz/1.2MHz,Low-Noise Step-Up
Current-Mode PWM Controller
Reflow Profiles
Profile Feature
Average ramp-up rate
(TL to TP)
Preheat
-Temperature Min(Tsmin)
-Temperature Max (Tsmax)
-Time (min to max)(ts)
Tsmax to TL
-Ramp-up Rate
Time maintained above:
-Temperature (TL)
-Time (tL)
Peak Temperature(TP)
Time within 5°C of actual Peak
Temperature (tP)
Ramp-down Rate
Time
25°C
to
Peak
Temperature
Sn-Pb Eutectic Assembly
Large Body
Small Body
Pkg. thickness
Pkg. thickness
<2.5mm or Pkg.
≥2.5mm or Pkg.
3
volume ≥350mm3 volume <350mm
3°C/second max.
Pb-Free Assembly
Large Body
Small Body
Pkg. thickness
Pkg. thickness
≥2.5mm or Pkg.
≥2.5mm or Pkg.
volume ≥350mm3 volume ≥350mm3
3°C/second max.
100°C
150°C
60-120 seconds
150°C
200°C
60-180 seconds
3°C/second max.
183°C
60-150 seconds
217°C
60-150 seconds
225+0/-5°C
10-30 seconds
240+0/-5°C
10-30 seconds
6°C/second max.
6 minutes max.
245+0/-5°C
10-30 seconds
250+0/-5°C
20-40 seconds
3°C/second max.
8 minutes max.
*All temperatures refer to topside of the package, measured on the package body surface.
7F, No.9, PARK AVENUE II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 Fax: 886-3-563-0879
WWW: http://www.aimtron.com.tw
3/24/06 REV 1.1
Email: service@aimtron.com.tw
9