Page No. : 1/8
RS6501
150KHz, 40V, 2A PWM Buck DC/DC Converter
General Description
The RS6501 is Monolithic IC that design for a step‐down DC/DC Converter, and own the ability of driving a 2A load without
additional transistor component.
The output version included 3.3V, 5V, 12V and an adjustable type. It operates at a switching frequency of 150KHz thus
allowing smaller sized filter components than what would be needed with lower frequency switching regulators. Other
features include a guaranteed ±4% tolerance on output voltage under specified input voltage and output load conditions,
and
±15%
on the oscillator frequency. Regarding protected function, thermal shutdown is to prevent over temperature
operating from damage, and current limit is against over current operating of the output switch.
Features
●
●
●
●
●
●
●
●
●
●
Applications
●
Simple High‐efficiency step‐down regulator
3.3V, 5V, 12V and adjustable
●
Positive to negative converter
Adjustable version output voltage range: 1.23‐37V
●
On‐card switching regulators
±4% max over line and load conditions
150KHz ±15% fixed switching frequency
TTL shutdown capability
Operating voltage can be up to 40V
Output load current: 2A
SOP‐8 package
Low power standby mode
Thermal‐shunt down and current‐limit protection
●
Built‐in switching a transistor on chip, requires only 4
external components
Application Circuits
VCC_INPUT
1
2
3
4
U1
VIN
Output
FB
SD
GND
GND
GND
GND
8
7
6
5
DS-SS33
2
1
1
L1
33uH
2
+5.0V
1
220uF/25V
1
1
C4
220uF/25V
+
C5
1
2
R1
+
C2 3.1K(0805)
21
R2
1K(0805)
2
1
R1
10
2
2
0.1uF
2
1
D1
2
C3
1000pF
1
2
0.1uF
C1
RS6501-ADS
Adjustable Output Voltage Version
This integrated circuit can be damaged by ESD. Orister Corporation recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
DS‐RS6501‐06
September, 2010
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Page No. : 2/8
Pin Assignments
SOP‐8(EP)
PACKAGE
PIN
1
2
3
4
5, 6, 7, 8 ,9
SYMBOL
VIN
VOUT
FB
SD
GND
DESCRIPTION
Regulator Input Pin
Regulator Output Pin
Output Voltage Feed Back Control Pin
ON/OFF Shutdown Pin
Ground Pin
SOP‐8(EP)
Ordering Information
DEVICE
DEVICE CODE
XX is nominal output voltage (for example, AD=ADJ, 33 = 3.3V, 50 = 5.0V, 12 = 12V).
Y is package designator :
SE : SOP‐8(EP)
Z is Lead Free designator :
P: Commercial Standard, Lead (Pb) Free and Phosphorous (P) Free Package
G: Green (Halogen Free with Commercial Standard)
RS6501‐XX YY Z
Block Diagram
SD
VIN
Current
Source
Bias
+
+
220mV
R
1.235V
Reference
2.5V
Regulator
Start
Up
200mV
+
COMP
-
Current
Limit
FB
R2
+
AMP
-
+
COMP
-
-
COMP
+
150KHz
OSC.
-
COMP
+
3A
Switch
Driver
Thermal
Limit
R1=2.5K
Output
GND
DS‐RS6501‐06
September, 2010
www.Orister.com
Page No. : 3/8
Absolute Maximum Ratings
(Note1)
Parameter
Supply Voltage
On/Off Pin Input Voltage
Feedback Pin Voltage
Output Voltage to Ground
Power Dissipation
Operating Temperature
Storage Temperature
Operating Junction Temperature Range
Operating Voltage
Symbol
V
CC
V
SD
V
FB
V
OUT
P
D
T
opr
T
stg
T
J
V
OP
Value
40
‐0.3~+25
‐0.3~+25
‐1
Internally Limited
0~+70
‐65~+150
‐40~+125
+4.5~+40
Unit
V
V
V
V
W
o
C
o
C
o
C
V
Electrical Characteristics (Continued)
Specifications with boldface type apply over for full operating temperature range, the other type are for TJ=25oC
(Note 2)
Part No.
Parameter
Symbol
Conditions
Min.
Typ.
Max.
Output Voltage
V
OUT
5V≤V
IN
≤40V, 0.2A≤I
LOAD
≤2A
3.135 3.3
3.465
RS6501‐3.3V
Efficiency
V
IN
=12V, I
LOAD
=2A
‐
72
‐
η
Output Voltage
V
OUT
7V≤V
IN
≤40V, 0.2A≤I
LOAD
≤2A
4.750 5.0
5.250
RS6501‐5.0V
Efficiency
V
IN
=12V, I
LOAD
=2A
‐
79
‐
η
Output Voltage
V
OUT
15V≤V
IN
≤40V, 0.2A≤I
LOAD
≤2A
11.40
12.0
12.60
RS6501‐12V
Efficiency
V
IN
=25V, I
LOAD
=2A
‐
90
‐
η
4.5V≤V
IN
≤40V, 0.2A≤I
LOAD
≤2A
1.193 1.230 1.280
Reference Voltage
V
FB
V
OUT
programmed for 3V
RS6501‐ADJ
Efficiency
V
IN
=12V, I
LOAD
=2A
‐
72
‐
η
Unit
V
%
V
%
V
%
V
%
All Output Voltage Versions Electrical Characteristics
Specifications with boldface type apply over for full operating temperature range, the other type are for T
J
=25
o
C
(Unless otherwise specified, V
IN
=12V for the 3.3V, 5V, and adjustable version and V
IN
=24V for the 12V version, I
LOAD
=500mA)
Parameter
Feedback Bias Current
Oscillator Frequency
Saturation Voltage
Max. Duty Cycle (ON)
Min. Duty Cycle (OFF)
Current Limit
Output Leakage Current
Quiescent Current
Standby Quiescent Current
Thermal Resistance
Symbol
I
b
f
O
V
SAT
DC
I
CL
I
L
I
Q
I
STBY
θ
JC
θ
JA
(Note 10)
V
IH
V
IL
I
IH
I
IL
Test Condition
Device Parameters
Adjustable Version Only, V
FB
=1.3V
(Note 5)
I
OUT
=2A (Note 6,7)
(Note 7)
(Note 8)
Peak Current (Note 6,7)
Output=0V (Note 6,8)
(Note 8)
ON/OFF pin=5V (Note 9)
SOP‐8
SOP‐8
ON/OFF Control
ON/OFF Pin Logic Input Threshold Voltage
ON/OFF Pin Input Current
Low (Regulator ON)
High (Regulator OFF)
V
LOGIC
=2.5V (Regulator OFF)
V
LOGIC
=0.5V (Regulator ON)
‐
2.0
‐
‐
1.4
6
0.02
0.6
‐
15
5
V
uA
Junction to Case
Junction to ambient
Min.
‐
127
110
‐
‐
‐
‐
‐
‐
‐
‐
Typ.
40
150
1.16
100
0
3.6
‐
5
85
15
70
Max.
50
100
173
173
1.4
1.5
‐
‐
50
30
200
300
‐
‐
o
o
Unit
nA
KHz
V
%
A
uA
mA
uA
C/W
C/W
DS‐RS6501‐06
September, 2010
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Page No. : 4/8
NOTE:
1.
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate
conditions for which the device is intended to be functional, but do not guarantee specific performance limits. For
guaranteed specifications and test conditions, see the Electrical Characteristics.
2.
External components such as the catch diode, inductor, input and output capacitors, and voltage programming
resistors can affect switching regulator system performance.
3.
Typical numbers are at 25
o
C and represent the most likely norm.
4.
All limits guaranteed at room temperature (standard type face) and at temperature extremes (bold type face). All room
temperature limits are 100% production tested. All limits at temperature extremes are guaranteed via correlation using
standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level
(AOQL).
5.
The switching frequency is reduced when the second stage current limit is activated.
6.
No diode, inductor or capacitor connected to output pin.
7.
Feedback pin removed from output and connected to 0V to force the output transistor switch ON.
8.
Feedback pin removed from output and connected to 12V for the 3.3V, 5V, ADJ. version, and 15V for the 12V version,
to force the output transistor switch OFF.
9.
V
IN
=40V.
10. Junction to ambient thermal resistance. (With copper area of approximately 3in
2
)
DS‐RS6501‐06
September, 2010
www.Orister.com
Page No. : 5/8
Characteristics Curve
Normalized Output Voltage
1.5
V
IN
=12V
I
LOAD
=200mA
160
140
120
Shutdown Quiescent Current
1
Output Voltage Change (%)
.
.
Current (uA)
0.5
100
80
60
40
V
ON
/V
OFF
=5V
T
J
=25
o
C
0
-0.5
-1
20
-1.5
0
25
50
75
100
o
125
150
175
0
0
10
20
30
Supply Voltage (V)
40
Junction Temperature ( C)
Switch Current Limit
6.00
5.90
1.30
V
IN
=12V
T
J
=25
o
C
1.20
Switch Saturation Voltage
Switch Current Limit (A)
5.70
5.60
5.50
5.40
5.30
5.20
0
25
50
75
100
o
Saturation Voltage (V)
5.80
1.10
V
IN
=12V
V
OUT
=5V
1.00
0.90
0.80
125
150
0
1
2
3
4
Junction Temperature ( C)
Switch Current (A)
On/Off Pin Current (Sinking)
12
10
Vin=22V
8
Current (uA)
6
4
2
0
0
5
10
15
20
25
30
Tj=25
℃
On/Off Pin Voltage (V)
DS‐RS6501‐06
September, 2010
www.Orister.com