SP6850
Green-Mode PWM Controller
DESCRIPTION
The SP6850 is the current mode PWM controller
with green-mode power-saving operation, to meet the
low standby-power needs of low-power SMPS. This
green-mode function enables the power supply to
easily meet even the strictest power conservation
requirements. The functions such as the leading-edge
blanking of the current sensing, internal slope
compensation and the small package provide the high
efficiency / low cost for SMPS power applications.
SP6850 is processed by BiCMOS fabrication, that
enables reducing the start-up current and the
operating current. SP6850 is available by SOT-23-6L
/ DIP-8P packages.
APPLICATIONS
AC/DC Switching Power Adaptor
Battery Charger
PC 5V Standby Power.
Open-Frame Switching Power Supply
FEATURES
High-Voltage BiCMOS Process
Very Low Startup Current (Typ
~
8µA)
Under Voltage Lockout (UVLO )
Current Mode Control with Cycle Peak
Current Limiting
Leading-Edge Blanking
Programmable Switching Frequency
Internal Slope Compensation
Green-Mode Control for Power Saving
Non-audible-noise Green Mode Control
300mA Driving Capability
OVP (Over Voltage Protection) on Vcc Pin
PIN CONFIGURATION
SOT-23-6L
DIP-8P
PART MARKING
SOT-23-6L
DIP-8P
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Ver.3
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SP6850
Green-Mode PWM Controller
TYPICAL APPLCATION CIRCUIT
TYPICAL APPLCATION CIRCUIT ( High Efficiency SMPS + Synchronous Rectifier )
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Ver.3
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SP6850
Green-Mode PWM Controller
PIN DESCRIPTION
SP6850D8TG
Pin
Symbol
Description
1
OUT Gate driver output to drive the external MOSFET
2
VCC Supply Voltage in
3
NC
Unconnected pin
Current sense. This pin senses the voltage across a resistor, to control PWM output. This pin
4
CS
also provides current amplitude information for current-mode control.
5
RT
This current is used to charge an internal capacitor, to determine the switching frequency.
6
NC
Unconnected pin
Voltage feedback. The pin provides the output voltage regulation signal., it provides feedback
7
COMP
to the internal PWM comparator, so that the PWM comparator can control the duty cycle.
8
GND Ground
SP6850S26RG
Pin
Symbol
Description
1
GND Ground
Voltage feedback. The pin provides the output voltage regulation signal., it provides feedback
2
COMP
to the internal PWM comparator, so that the PWM comparator can control the duty cycle
3
RT
This current is used to charge an internal capacitor, to determine the switching frequency.
Current sense. This pin senses the voltage across a resistor, to control PWM output. This pin
4
CS
also provides current amplitude information for current-mode control
5
VCC Supply Voltage in
6
OUT Gate driver output to drive the external MOSFET
BLOCK DIAGRAM
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Ver.3
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SP6850
Green-Mode PWM Controller
ORDERING INFORMATION
Part Number
Package
Part Marking
SP6850I
SP6850I
85AYW
850YW
SP6850AD8TG
DIP-8P
SP6850BD8TG
DIP-8P
SP6850AS26RG
SOT-23-6L
SP6850BS26RG
SOT-23-6L
※
SP6850AD8TG / SP6850BD8TG : Tube ; Pb – Free
※
SP6850AS26RG / SP6850BS26RG : Tape Reel ; Pb – Free
ABSOULTE MAXIMUM RATINGS
(T
A
=25
℃
, unless otherwise specified.)
Symbol
V
CC
V
COMP / RT / CS
P
D
ESD
T
ope
T
J
T
STG
T
LEAD
R
ӨJC
Parameter
DC Supply Voltage
COMP / RT / CS Voltage
Power Dissipation @ T
A
=85
℃
(*)
Human Body Model
Machine Model
Operating Ambient Temperature
Operating Junction Temperature Range
Storage Temperature Range
Pb-Free Lead Soldering Temperature for 5 sec.
Thermal Resistance Junction – Case (*)
SOT-23-6L
DIP-8P
The following ratings designate persistent limits beyond which damage to the device may occur
.
Value
36
-0.3 ~ 7.0
0.3
4
300
-40 ~ 85
-40 ~ 150
-40 ~ 150
260
210
95
Unit
V
V
W
KV
V
℃
℃
℃
℃
℃
/W
(*) The power dissipation and thermal resistance are evaluated under copper board mounted with free air conditions.
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SP6850
Green-Mode PWM Controller
ELECTRICAL CHARACTERISTICS
(T
A
=25
℃
, V
CC
=15V, unless otherwise specified.)
Symbol
Parameter
Supply Voltage ( Vcc Pin )
I
stt
Startup
Current
I
op
Operating Current
UVLO
(off)
Min. Operating Voltage
UVLO
(on )
Start Threshold Voltage
OVP Level Over Voltage Protection
Voltage Feedback ( Comp Pin )
Isc
Short Circuit Current
Vop
Open Loop Voltage
V
TH(GM)
Green Mode Threshold VCOMP
Oscillator ( RT Pin )
F
OSC
Frequency
F
OSC(GM)
Green Mode Frequency
Fdt
Frequency Variation versus Temp. Deviation
Fdv
Frequency Variation versus V
CC
Deviation
Current Sensing ( CS Pin )
Vcs(off)
Maximum Input Voltage
Conditions
V
COMP
= 3V
Min.
Typ.
8
2
10.0
16.0
2.2
5.0
2.35
Max.
20
4
11.0
17.0
36
3.0
Unit
uA
mA
V
V
V
mA
V
V
KHz
KHz
%
%
9.0
15.0
28
R
T
=100KΩ
Fs=65.0KHz
(-40°C ~105°C)
(V
CC
=11V-25V)
SP6850BD8TG
SP6850BS26RG
SP6850AD8TG
SP6850AS26RG
60.0
65.0
20
75.0
3
1
0.8
0.7
0.85
0.75
50
150
0.9
V
0.8
KΩ
nS
80
1
%
%
V
V
Zcs
Input impedance
T
PD
Delay to Output
Gate Driver Output ( OUT Pin )
DC
(Max)
Maximum Duty Cycle
DC
(Min)
Minimum Duty Cycle
V
OL
V
OH
Tr
Tf
70
V
CC
=15V,
Io=20mA
V
CC
=15V,
Io=20mA
Load Cap=1000pF
Load Cap=1000pF
75
0
Output Low Level
Output High Level
Rising Time
Falling Time
8
50
30
200
120
nS
nS
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Ver.3
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