3-Pin Synchronous Step-Up DC/DC Converter F eatures
n Schottky Diode Embedded, Saving Cost and Space n Low Start-up Voltage (0.9V) n High Efficiency up to 88% n Low Quiescent Current n Low Ripple and Noise n Available Output Voltage: 2.0V,2.7V,2.8V, 3.0V, 3.3V,3.8V and 5.0V n Space Saving Packages: SOT-89, SOT-23 n Pb-Free Package
PAM2400
General Description
The PAM2400 is a high efficiency step-up DC/DC converter, delivering a fixed output voltage of 2.0V, 2.7V, 2.8V, 3.0V, 3.3V, 3.8V or 5.0V. The device starts up with an input voltage as low as 0.9V at 1mA load. The Pulse Frequency Modulation (PFM) scheme provides optimized performance for applications with light load and low input voltages. The PAM2400 employs a built-in synchronous rectifier, instead of requiring an external Schottky diode, so that to improve system efficiency and save system cost and PCB area. The internal PFM control circuit operates at constant switching frequency of 100KHz. Only three external components are required. The space saving SOT-89 and SOT-23 packages make t h e PA M 2 4 0 0 i d e a l f o r s p a c e c o n s c i o u s applications.
Applications
n n n n n n
Pagers Cameras Wireless Microphones Pocket Organizers Battery Backup Suppliers Portable Instruments
Typical Application
V IN
L1 100 μ H
VO
Block Diagram
SW
PAM2400
VOUT
VOUT
1M
SW
GND +
C IN 22 μ F
+
+
CO 47 μ F
1.25V REF
Enable GND
OSC 100KHz
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3-Pin Synchronous Step-Up DC/DC Converter P in Configuration & Marking Information
SOT89-3 V: Voltage Code X: Internal Code Y: Year W: Week
PAM2400
P2400V XXXYW
1
2 SOT23-3
3
3
CC: Product Code of PAM2400 V: Voltage Code Y: Year W: Week
CCVYW
1
Pin Number 1 2 3
2
Name GND VOUT SW Ground Output Switch Pin Function
Absolute Maximum Ratings
These are stress ratings only and functional operation is not implied . Exposure to absolute maximum ratings for prolonged time periods may affect device reliability . All voltages are with respect to ground . Supply Voltage............................................ 6.0V SW pin Voltage............................................. 6.0V SW pin Switch Current..................................0.4A Operating Temperature Range.........-40 ° C to 85 ° C Storage Temperature Range...........-65 ° C to 150 ° C Lead Temperature (Soldering 5 Sec.)...........300 ° C
Thermal Information
Parameter Thermal Resistance (Junction to Case) Thermal Resistance (Junction to Ambient) Internal Power Dissipation Symbol θJC θJA PD Package SOT89-3 SOT-23 SOT89-3 SOT-23 SOT89-3 SOT-23 Maximum 45 130 160 250 550 400 Unit °C/W °C/W mW
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3-Pin Synchronous Step-Up DC/DC Converter E lectrical Characteristic
C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted.
Parameter Output Voltage Accuracy Input Voltage Start-Up Voltage Hold-on Voltage Supply Current (Vo pin) VIN VSTA RT VHOLD IDD1 IDD2 IO=1mA IO=0mA,V IN =2V to 0V VO =VO X 1.05 VO =VO X 0.95 Vo=2.0V Vo=2.7V No-Load Input Current IIN IO=0mA, VIN =1.5V Vo=2.8V Vo=3.0V Vo=3.3V Vo=3.8V Vo=5.0V SW Leakage Current SW Switch-On Resistance Oscillator Duty Cycle Oscillator Frequency Efficiency (Note 2) R ON DC fOS C η VSW =5V,V IN =V O+0.5V Isw=50mA VIN =VO * 90%
Current Limit Appears
PAM2400
Symbol
Test Conditions VIN =1.5V, IO=1mA
MIN -3
TYP
MAX +3 5.5
UNIX % V V V μA μA
0.9 0.4 8.5 33 19 23 25 26 29 34 45
1.0 0.6 12
μA
1.0 1.0 70 70 80 100 85 90 130
μA Ω % kHz %
Peak value
Note 1: V O means the nominal output voltage Note 2: Refer to “Efficiency vs Output Current” curve
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3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics
C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=2.0V 1.Output voltage vs Output current 4. Output Voltage vs Temperature
PAM2400
2.4 2.2
2.1
Output voltage(V)
Output voltage(V)
Vin=0.9V Vin=1.2V Vin=1.5V
2.06 2.02 1.98 1.94 1.9
2 1.8 1.6 1.4 0 30 60 90 120 150 Output current(mA)
0
30
60
90
120
150
Temperature(℃)
90 80 70
2.Efficiency vs Output Current
14 12 10
5. I DD1 vs Temperature
Efficiency(%)
IDD1(uA)
Vin=0.9V Vin=1.2V Vin=1.5V
60 50 40 30 20 10 0 0 20 40 60 80 100 120 Output current(mA)
8 6 4 2 0 0 30 60 90 120 150 Temperature( ℃)
1.2 1
3.Start up Voltage and Hold on voltage vs Output Current
Input voltage(V)
0.8 0.6 0.4 0.2 0 0 5 10 15 Output current(mA) 20 25
Start up Hold on
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3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics (continued)
C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=2.7V
3 2.5
PAM2400
1.Output voltage vs Output current
2.8
4. Output Voltage vs Temperature
Output voltage(V)
2
Output voltage(V)
2.76 2.72 2.68 2.64 2.6
1.5 1
Vin=0.9V Vin=1.2V Vin=1.5V
0.5 0 0 30 60 Output current(mA) 90
120
0
30
60
90
120
150
Temperature(℃)
90% 80% 70%
2.Efficiency vs Output Current
16 14 12
5. I DD1 vs Temperature
IDD1(uA)
Vin=0.9V Vin=1.2V Vin=1.5V
Efficiency
60% 50% 40% 30% 20% 10% 0% 0 20 40 60 80 100 120 Output current(mA)
10 8 6 4 2 0 0 30 60 90 120 150 Temperature(℃)
1.2 1 0.8
3.Start up Voltage and Hold on voltage vs Output Current
Vin(V)
0.6 0.4 0.2 0 0 5 10 15 Output current(mA) 20 25
Start up Hold on
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3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics (continued)
C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=2.8V
3 2.5
PAM2400
1.Output voltage vs Output current
2.9
4. Output Voltage vs Temperature
Output voltage(V)
2 1.5 1 0.5 0 0 30 60 Output current(mA) 90 120
Vin=0.9V Vin=1.2V Vin=1.5V
Output voltage(V)
2.86 2.82 2.78 2.74 2.7 0 30 60 90 120 150 Temperature(℃)
2.Efficiency vs Output Current
90% 80% 70%
16 14 12
5. I DD1 vs Temperature
Efficiency
50% 40% 30% 20% 10% 0% 0 30 60 Output current(mA) 90 120
Vin=0.9V Vin=1.2V Vin=1.5V
IDD1(uA)
60%
10 8 6 4 2 0 0 30 60 90 120 150 Temperature( ℃)
1.4 1.2
3.Start up Voltage and Hold on voltage vs Output Current
Input voltage(V)
1 0.8 0.6 0.4 0.2 0 0 5 10 15 20 Output current(mA)
Start up Hold on
25
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3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics (continued)
C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=3.0V
3.2 3
PAM2400
1.Output voltage vs Output current
3.1
4. Output Voltage vs Temperature
2.8 2.6 2.4 2.2 2 0 30 60 Output current(mA) 90 120
Vin=0.9V Vin=1.2V Vin=1.5V
Output Voltage(V)
3.06 3.02 2.98 2.94 2.9 0 30 60 90 120 150 Temperature(℃)
Output voltage(V)
100 90 80 70 60 50 40 30 20 10 0 0
2.Efficiency vs Output Current
16 14 12
5. I DD1 vs Temperature
Efficiency(%)
IDD1(uA)
Vin=0.9V Vin=1.2V Vin=1.5V
10 8 6 4 2 0
30
60 Output current(mA)
90
120
0
30
60
90
120
150
Temperature( ℃)
3.Start up Voltage and Hold on voltage vs Output Current
1.2 1
Input voltage(V)
0.8 0.6 0.4 0.2 0 0 5 10 15 20 25 Output current(mA)
Start up Hold on
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3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics (continued)
C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=3.3V
4 3.5
PAM2400
1.Output voltage vs Output current
3.4 3.36
4. Output Voltage vs Temperature
Output voltage(V)
2.5 2 1.5 1 0.5 0 0 30 60 90 120 Output current(mA) 150
Vin=0.9V Vin=1.2V Vin=1.5V Vin=1.8V Vin=2.0V
Output Voltage(V)
3
3.32 3.28 3.24 3.2 0 30 60 90 120 150 Temperature( ℃)
2.Efficiency vs Output Current
90% 85% 80%
16 14 12
5. I DD1 vs Temperature
IDD1(uA)
150
Efficiency
75% 70% 65% 60% 55% 50% 0 30 60 90 120 Output current(mA)
Vin=0.9V Vin=1.2V Vin=1.5V Vin=1.8V Vin=2V
10 8 6 4 2 0 0 30 60 90 120 150 Temperature(℃)
1.4 1.2
3.Start up Voltage and Hold on voltage vs Output Current
Input voltage(V)
1 0.8 0.6 0.4 0.2 0 0 5 10 15 20 25 Output current(mA)
Start up Hold on
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3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics (continued)
C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=3.8V
4 3.5
PAM2400
1.Output voltage vs Output current
3.9 3.86
4. Output Voltage vs Temperature
Output voltage(V)
2.5 2 1.5 1 0.5 0 0 30 60 90 Output current(mA)
Vin=0.9V Vin=1.2V Vin=1.5V Vin=1.8V Vin=2V
Output voltage(V)
3
3.82 3.78 3.74 3.7
120
0
30
60
90
120
150
Temperature( ℃)
2.Efficiency vs Output Current
90% 80%
18 16 14 12 10 8 6 4 2 0
5. I DD1 vs Temperature
60%
Vin=0.9V
50% 40% 30%
Vin=1.2V Vin=1.5V Vin=1.8 Vin=2V
IDD1(uA)
Efficiency
70%
0
30
60
Output current(mA)
90
120
0
30
60
90
120
150
Temperature(℃)
1.4 1.2
3.Start up Voltage and Hold on voltage vs Output Current
Input voltage(V)
1 0.8 0.6 0.4 0.2 0 0 5 10 15 20 25 Output current(mA)
Start up Hold on
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3-Pin Synchronous Step-Up DC/DC Converter Typical Performance Characteristics (continued)
C IN=22 μ F,C O=47 μ F,T A=25°C, unless otherwise noted. Vo=5.0V
6 5
PAM2400
1.Output voltage vs Output current
5.1
4. Output Voltage vs Temperature
Output voltage(V)
4 3 2 1 0 0 30 60 Output current(mA) 90
Vin=0.9V Vin=1.2V Vin=1.5V Vin=1.8V Vin=2V
Output Voltage(V)
5.06 5.02 4.98 4.94 4.9
120
0
30
60
90
120
150
Temperature(℃)
2.Efficiency vs Output Current
95% 90% 85%
20 25
5. I DD1 vs Temperature
Efficiency
IDD1(uA)
Vin=0.9V Vin=1.2V Vin=1.5V Vin=1.8V Vin=2V
80% 75% 70% 65% 60% 55% 50% 0
15 10 5 0
20
40
60
80
100
120
0
30
60
90
120
150
Output current(mA)
Temperature( ℃)
1.4 1.2
3.Start up Voltage and Hold on voltage vs Output Current
Input voltage(V)
1 0.8 0.6 0.4 0.2 0 0 5 10 15 20 25 Output current(mA)
Start up Hold on
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3-Pin Synchronous Step-Up DC/DC Converter Application Information
Inductor Selection To select an inductor for PAM2400 applications, it should be noted that the inductors current saturation rating should be larger than the possible peak inductor current to ensure proper operation, and it should have low DCR (DC resistance). Using an inductor with the saturation current lower than the possible peak indicator current can cause a dramatic drop in the inductance and severely decay the maximum output current levels. An inductor is chosen based on desired ripple current. Larger inductors result in lower ripple currents, and smaller ones higher ripple. A 100uH inductor will b e a s u i t a b l e c h o i c e f o r m o s t PA M 2 4 0 0 applications. The following equation can also help to get a good approximate value for the inductor. L=V IN*D /(△I L* f ) D ( Duty Cycle) = 1 - V IN/ V OUT ΔI L (Ripple Current) in the Inductor, i.e., 20% to 40% of the maximum inductor current(Ip). F (Switching Frequency)=100K. Output and Input Capacitor Selection Input Capacitor An input capacitor of minimum 22μF is recommended to reduce input ripple and switching noise for normal operating conditions. A larger capacitor with lower ESR (Equivalent Series Resistance) may be needed if the application requires very low input ripple. Usually ceramic capacitors are a good choice for applications. Note that the input capacitor should be located as close as possible to the IC. Output Capacitor A minimum 47μF output capacitor is recommended and may-be a larger one is better. The total output voltage ripple has two components, the capacitive ripple caused by the charging and discharging on the output capacitor, and the ohmic ripple due to the capacitor's equivalent series resistance (ESR): V RIPPLE=V RIPPLE(C)+V RIPPLE(ESR) V RIPPLE(C) ≈1 / 2 *( L /( C ( OUT) *(( V OUT( MAX) - V IN( MIN) ) ) ) ) *( I 2PEAK- I 2OUT) And V RIPPLE( ESR) = I PEAK* R ESR( COUT) Where Ipeak is the peak inductor current . Multilayer ceramic capacitors are a good choice as they have extremely low ESR and are available in small footprints. Capacitance and ESR variation vs temperature should be considered for best performance in applications with wide operating temperature ranges. Component Power Dissipation Operating in discontinuous mode, power loss in the winding resistance of the inductor is approximately equal to PDL=2/3(T ON/L)*R D*((V OUT+V F)/V OUT)*P OUT The power dissipated in a switch loss is PDsw=2/3(T ON/L)*R ON*((V OUT+V D-V IN)/V OUT)*(P OUT) The power disspated in rectifier diode(Internal Diode) is PDd=V D*I OUT Where POUT=VOUT*IOUT, RD=Inductor DCR, V D=Diode drop PC Board Layout considerations Careful PC board layout is important for minimizing ground bounce and noise. Keep the IC's GND pin and the ground leads of input and output capacitors as close as possible. In addition, connect L1 and SW with short and wide connections.
PAM2400
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3-Pin Synchronous Step-Up DC/DC Converter O rdering Information
PAM2400 X X X XXX
Output Voltage Number of Pins Package Type Pin Configuration
Pin Configuration A Type 1. GND 2. VOUT 3. SW Package Type A: SOT-23-3 C: SOT-89-3 Number of Pins A: 3 Output Voltage 200: 2.0V 270: 2.7V 280: 2.8V 300: 3.0V 330: 3.3V 380: 3.8V 500: 5.0V
PAM2400
Part Number PAM2400AAA200 PAM2400ACA200 PAM2400AAA270 PAM2400ACA270 PAM2400AAA280 PAM2400ACA280 PAM2400AAA300 PAM2400ACA300 PAM2400AAA330 PAM2400ACA330 PAM2400AAA380 PAM2400ACA380 PAM2400AAA500 PAM2400ACA500
Output Voltage 2.0V 2.0V 2.7V 2.7V 2.8V 2.8V 3.0V 3.0V 3.3V 3.3V 3.8V 3.8V 5.0V 5.0V
Marking CCGYW P2400G XXXYW CCHYW P2400H XXXYW CCRYW P2400R XXXYW CCCYW P2400C XXXYW CCDYW P2400D XXXYW CCEYW P2400E XXXYW CCFYW P2400F XXXYW
Package Type SOT-23-3 SOT-89-3 SOT-23-3 SOT-89-3 SOT-23-3 SOT-89-3 SOT-23-3 SOT-89-3 SOT-23-3 SOT-89-3 SOT-23-3 SOT-89-3 SOT-23-3 SOT-89-3
MOQ 3,000Unites/Tape&Reel 1,000Unites/Tape&Reel 3,000Unites/Tape&Reel 1,000Unites/Tape&Reel 3,000Unites/Tape&Reel 1,000Unites/Tape&Reel 3,000Unites/Tape&Reel 1,000Unites/Tape&Reel 3,000Unites/Tape&Reel 1,000Unites/Tape&Reel 3,000Unites/Tape&Reel 1,000Unites/Tape&Reel 3,000Unites/Tape&Reel 1,000Unites/Tape&Reel
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3-Pin Synchronous Step-Up DC/DC Converter O utline Dimension
SOT89-3
PAM2400
4 . 5 0 . 05 1 . 650 REF 1 . 400 REF 1 . 50 0 . 05
4 . 20 0 . 05
2 . 5 0 . 05
1 . 00 0 . 07 1 . 50 1 . 50 3 . 00 0 . 025 6’-2X
6’ 0 . 46 0 . 025 0 . 38 0 . 01
6’-2X
( Unit : mm )
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3-Pin Synchronous Step-Up DC/DC Converter O utline Dimension
SOT23-3
PAM2400
D B A
A1
E
H
Dim
S e
Millimeters Min. 1.00 0.00 0.35 0.10 2.70 1.40 2.40 0.37 Typ. 1.15 0.05 0.43 0.175 2.90 1.60 1.90BSC 2.70 3.00 Max. 1.30 0.10 0.51 0.25 3.10 1.80
A A1 B C D E e H L
L
C
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