PAM2310
2A Low Noise Step-Down DC-DC Converter
Features
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Output Current: Up to 2A
Output Voltage: 0.6V to V
IN
Input Voltage: 2.7V to 5.5V
Peak Efficiency up to 95%
42
μ
A (Typ) No Load Quiescent Current
Shutdown Current: <1
μ
A
100% Duty Cycle Operation
1.5MHz Switching Frequency
Internal Soft Start
No external Compensation Required
Current Limit Protection
Thermal Shutdown
SOP-8 Package
Description
T h e PA M 2 3 1 0 i s a 2 A s t e p - d o w n D C - D C
converter. At heavy load, the constant-frequency
PWM control performs excellent stability and
transient response. No external compensation
components are required
.
The PAM2310 supports a range of input voltages
from 2.7V to 5.5V, allowing the use of a single
L i + /L i - p o l y m e r c e l l , m u l ti p l e A l k a l i n e /N i M H
cell,and other standard power sources. The
output voltage is adjustable from 0.6V to the input
voltage. The PAM2310 employs internal power
switch and synchronous rectifier to minimize
external part count and realize high efficiency.
During shutdown, the input is disconnected from
the output and the shutdown current is less than
1
μ
A. Other key features include over-temperature
and short circuit protection, and under-voltage
lockout to prevent deep battery discharge.
The PAM2310 delivers 2A maximum output
current while consuming only 42
μ
A of no-load
quiescent current. Ultra-low RDS(ON) integrated
MOSFETs and 100% duty cycle operation make
the PAM2310 an ideal choice for high output
voltage, high current applications which require a
low dropout threshold.
The PAM2310 is available in SOP-8 package.
Applications
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5V or 3.3V Point of Load Conversion
Telecom/Networking Equipment
Set Top Boxes
Storage Equipment
Video Cards
DDR Power Supply
Typical Application
L
VIN
VO
VIN (2)
CI N
(3)SW
22uF
PAM2310
EN(7)
(5)FB
0
R1
Cfw
100p
Co
22uF
R2
N C(1,6,8)
GND (4)
0
0
0
R
1
V
O
=
0.6
1
+
R
2
Power Analog Microelectronics
,
Inc
www.poweranalog.com
05/2011 Rev1.0
1
PAM2310
2A Low Noise Step-Down DC-DC Converter
Block Diagram
1.5M
OSC
SLOPE
COMP
+
IAMP
-
VIN
FB
FREQ
SHIFT
OSC
MAIN
SWITCH
(
PCH
)
S Q
R1
-
R2
VIN
R Q
RS LATCH
+
EA
COMP
SWITCHING
LOGIC
AND
BLANKING
CIRCUIT
ANTI
-
SHOOT
-
THRU
SYNCHRONOUS
RECTIFIER
(
NCH
)
SW
EN
0.6VREF
SHUTDOWN
+
IRCMP
-
GND
Pin Configuration & Marking Information
Top View
SOP-8
NC
VIN
SW
GND
NC
EN
NC
FB
P2310:PAM2310
V: Output Voltage
X: Internal Code
Y: Year
W: Week
Power Analog Microelectronics
,
Inc
www.poweranalog.com
05/2011 Rev1.0
2
PAM2310
2A Low Noise Step-Down DC-DC Converter
Pin Description
Name
NC
VIN
SW
GND
FB
NC
EN
NC
Pin Number
1
2
3
4
5
6
7
8
No Connected
Bias supply. Chip main power supply pin
The drains of the internal main and synchronous power MOSFET.
GND
Feedback voltage to internal error amplifier, the threshold voltage is 0.6V.
No Connected
Enable control input. Force this pin voltage above 1.5V, enables the chip, and
below 0.3V shuts down t he device.
No Connected
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.
Input Voltage V
I N
......................................6V
SW Pin Voltage......................-0.3V to (V
IN
+0.3V)
FB Pin Voltage.........................-0.3V to (V
IN
+0.3V)
EN Pin Voltage....................................- 0.3V to 6V
Maximum Junction Temperature..................150°
C
Storage Temperature Range...........-65° to 150°
C
C
Soldering Temperature.......................300° 5sec
C,
Recommended Operating Conditions
Supply Voltage..................................2.7V to 5.5V
Junction Temperature Range..........-40 ° to 125 °
C
C
Ambient Temperature Range...........-40 ° to 85 °
C
C
Thermal Information
Parameter
Thermal Resistance (Junction to Ambient)
Thermal Resistance (Junction to Case)
Internal Power Diss ipation (@TA=25°
C)
Symbol
θ
JA
θ
JC
P
D
Package
SOP-8
SOP-8
SOP-8
Maximum
90
11
1100
Unit
°
C/W
°
C/W
mW
Power Analog Microelectronics
,
Inc
www.poweranalog.com
05/2011 Rev1.0
3
PAM2310
2A Low Noise Step-Down DC-DC Converter
Electrical Characteristic
T
A
=25 ° ,
Vin=5.0V, Vo=1.8V, Cin=22uF,Co=22uF, L=2.2uH,
unless otherwise noted.
C
PARAMETER
Input Voltage Range
Output Voltage Range
Regulated Output Voltage Accuary
Regulated Feedback Voltage
FB Leak age Current
Output Voltage Line Regulation
Output Voltage Load Regulation
Quies cent Current
Shutdown C urrent
Peak Inductor Current
Oscillator Frequency
Drain-Source On-State Res istance
Start up Time
EN Threshold High
EN Threshold Low
EN Leakage Current
Over T emperature Protection
OTP
Hysteresis
SYM BOL
V
IN
V
O
V
O
V
F B
I
FB
LNR
LDR
I
Q
I
SD
I
LIM
f
OS C
R
DS( ON)
t
S
V
E H
V
E L
I
EN
OTP
OT H
V
IN
=V
EN
= 0V
-1.0
150
30
Isw=100mA
High Side
Low Side
1.5
0.3
1.0
V
O
=1V
V
IN
= 2.7V t o 5V
I
O
=0A to 2A
No load
V
E N
= 0V
3
1.5
90
70
0.5
0.2
0.5
42
90
1
I
O
= 0 to 2A,V
IN
=2.7V to 5.5V
Test Co nditions
MIN
2.7
0.6
-2
0.588
0.6
TYP
M AX
5.5
V
IN
+2
0.612
0.2
UNITS
V
V
%
V
µA
%/V
%/A
µA
µA
A
MH z
mΩ
mΩ
ms
V
V
µA
°
C
°
C
From enable to output regulation
Power Analog Microelectronics
,
Inc
www.poweranalog.com
05/2011 Rev1.0
4
PAM2310
2A Low Noise Step-Down DC-DC Converter
Typical Performance Characteristics
T
A
=25 ° , C
IN
=22uF,Co=22
μ
F, unless otherwise noted.
C
Efficiency vs Output Current (Vo=1.2V)
100
90
80
70
75
95
90
85
80
Efficiency vs Input Voltage (Vo=1.2V)
60
50
40
1
10
100
1000
10000
Vin=3.6V
Vin=5.0V
Vin=5.5V
Io=100mA
Io=1000mA
70
65
Io=2000mA
60
2.0
3.0
4.0
5.0
6.0
Output Current(mA)
Input Voltage(V)
Efficiency vs Output Current (Vo=1.8V )
100
90
80
70
80
1 00
95
90
85
Efficiency vs Input Voltage (Vo=1.8V)
60
50
40
1
10
100
1000
Io= 100mA
Vin=3.6V
Vin=5.0V
Vin=5.5V
10000
.
75
Io= 1000mA
70
Io= 2000mA
65
2.0
3.0
4.0
5.0
6.0
Ou t Cu
tpu rrent(m
A)
Efficiency vs Output Current(Vo=3.3V)
100
95
90
85
85
80
75
70
65
60
1
10
100
1000
10000
80
Vin=4.5V
Vin=5.0V
Vin=5.5V
75
70
65
4.0
Io=1000mA
Io=100mA
100
95
90
Input Voltage(V)
Efficiency vs Input Voltage (Vo=3.3V)
Io=2000mA
4.5
5.0
5.5
6.0
O utput C u rrent(mA)
Input Voltage(V )
Power Analog Microelectronics
,
Inc
www.poweranalog.com
05/2011 Rev1.0
5
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