ht7a6003v130.pdf

HT7A6003
EMI-Improved Green Mode PWM
Controller with Integrated Protections
Feature
General Description
• Frequency jitter for restraining EMI
HT7A6003 is an advanced, highly integration OffLine PWM Controller. This device provides many
protection functions with ultra low power circuit
design, and is optimized for restraining EMI. By
integrated a Non-Audible Noise Green Mode Control
Scheme and optimizing for the Energy Star 5.0 spec.,
the Power Supply Unit (PSU) implemented using
the HT7A6003 can satisfy the “Energy Star NoLoad Mode” Stand-by Power standard, which is
less than 0.3W within all Nameplate Output Power
Range of 0~250W. This device also integrated various
protection functions such as Short-Circuit Protection
(SCP, which can also be used for Over-Load
Protection, OLP), Cycle-by-Cycle Current Limiting,
Over Voltage Protection (OVP), and Soft-Start
function for reducing inrush current during system
initialization and preventing device burn-out.
• Integrated Soft-Start function
• Very low operating current and start-up current
(<20mA) for satisfying Energy-Star 5.0 "No-Load
Mode" (Stand-by) power standard
• ±5% trimmed oscillator for precise frequency
• Programmable switching frequency
• Non-audible-noise Green Mode Control
• LEB (Leading-Edge Blanking) on CS pin
• Internal slope compensation
• Cycle-by-Cycle current limiting
• Short-Circuit-Protection(SCP) for Short-Circuit
and Over-Load condition
• Over-Voltage-Protection(OVP) on VCC Pin
• 8-Pin SOP package
The HT7A6003 also integrates Leading-Edge
Blanking and Slope Compensation for minimizing
external components cost and system complexity.
Applications
• Switching AC-DC adaptor
• Open frames switching power supply
• UPS
• LCD TV
Application Circuits
EMI Filter
Flyback Converter
VOUT
RT
GD
HT7A6003
GND
CS
VCC
COMP
VREF
0.1 F
Rev. 1.30
Voltage Sense
GND
1
FOD817
TL431
March 25, 2016
HT7A6003
Block Diagram
Pin Assignment
VREF
VCC
UVLO
Soft-Start
14V / 8V
Driver
Stage
Green Mode
OSC
RT
COMP
VCC
Internal
Bias & Vref
32V OVP
S
GD
Q
GND
R
Frequency
Jitter
8
2
7
3
6
4
5
VREF
VCC
GD
GND
HT7A6003
8 SOP-A
Slop
Compensation
PWM
2R
COMP
NC
CS
RT
1
R
OCP
CS
SCP
LEB
350nS
1V
Pin Description
Pin No.
Pin Name
Description
1
COMP
2
N.C
No connection
3
CS
A voltage proportional to inductor current is connected to this input. The PWM generator
uses this voltage information to terminate the output switch conduction.
4
RT
The oscillator frequency is programmed by connecting a resistor RT between this pin and
ground. A maximum frequency of 500kHz is possible.
5
GND
6
GD
7
VCC
Positive Supply.
8
VREF
Reference output.
Voltage Feedback Pin. Connected to a Photo-Coupler for close-loop control.
Combined control circuitry and power ground.
Power MOSFET gate driver output.
Absolute Maximum Ratings
Supply Voltage VCC�������������������������������������������������������������������������������������������������������������������������������� -0.3V~30.0V
COMP, RT, CS Pins����������������������������������������������������������������������������������������������������������������������������������� -0.3V~5.5V
Junction Temperature������������������������������������������������������������������������������������������������������������������������������������������ 150°C
Operating Ambient Temperature��������������������������������������������������������������������������������������������������������������� -40°C~85°C
Storage Temperature Range�������������������������������������������������������������������������������������������������������������������� -65°C~150°C
Package Thermal Resistance (8-Pin SOP)����������������������������������������������������������������������������������������������������� 160°C/W
ESD Protection:
Human Body Model��������������������������������������������������������������������������������������������������������������������������������������3kV
Machine Model�������������������������������������������������������������������������������������������������������������������������������������������200V
Note: These are stress ratings only. Stresses exceeding the range specified under “Absolute Maximum Ratings”
may cause substantial damage to the device. Functional operation of this device at other conditions beyond
those listed in the specification is not implied and prolonged exposure to extreme conditions may affect
device reliability.
Rev. 1.30
2
March 25, 2016
HT7A6003
Electrical Characteristics
Unless otherwise stated, this specifications apply for 0°C ≤ Ta ≤ 70°C, VCC=15V, RT=10kW
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
Supply Voltage (VCC Pin)
IST
Startup Current
ICC
Operating Current
VTL
UVLO (Off)
VTH
UVLO (On)
VCC
OVP Trip Level
VCC
OVP Strobe Time
VCC=12.9V
—
12
30
mA
VCOMP=0V
—
2.0
3.0
mA
—
2.5
—
mA
7
8
9
V
VCOMP=3V
—
—
VCC(Over Voltage Protection)
—
13
14
15
V
26.5
28.0
29.5
V
—
80
—
ms
—
5.5
—
V
Reference Section
VREF
Output Voltage
Tj = 25°C, IO = 1mA
∆VREF
Line Regulation
12V ≤ VCC ≤ 25V
—
3
20
mV
∆VREF
Load Regulation
1mA ≤ IO ≤ 10mA
—
4
25
mV
Current Sensing (CS Pin)
VCS(OFF)
Maximum Input Voltage, Vcs(off)
—
0.9
1.0
1.1
V
tLEB
Leading Edge Blanking Time
—
—
350
—
ns
tD-OVP
Delay to Output
—
—
100
—
ns
Oscillator (RT pin)
Oscillator Frequency
Tj=25°C, RT=10kW (See Note *)
49
52
55
kHz
∆fOSC
∆TA
Temperature Stability
-40°C ~105°C
—
5
—
%
∆fOSC
∆VREF
Voltage Stability
VCC=10V~25V
—
0.2
1.0
%/V
DMAX
Maximum Duty
—
—
75
—
%
Frequency Jitter
—
—
±4
—
%
V
fOSC
Gate Drive Output (GD Pin)
VOL
Output Low Level
VCC=15V, Isink=20mA
—
—
1
VOH
Output High Level
VCC=15V, Isource=20mA
9
—
—
V
tr
Rising Time
Tj=25°C, Load Capacitance=1nF
—
50
150
ns
tf
Falling Time
Tj=25°C, Load Capacitance=1nF
—
50
150
ns
Voltage Feedback (COMP Pin)
ISINK
Short Circuit Current
VCOMP=0V
—
1.5
2.2
mA
VCOMP
Open Loop Voltage
COMP pin open
—
5.5
—
V
SCP Trip Level
VCOMP (SCP)
4.2
4.7
—
V
SCP Delay Time (See Note)
fS=52kHz
—
40
—
ms
Soft-Start Time
RT=10kW
—
8.5
—
ms
SCP (Short Circuit Protection)
VCOMP
Soft-Start
tSTART
Note: These Parameters, although guaranteed, are not 100% tested in production.
"*" It is necessary that the operating frequency is set at 40kHz~60kHz for Green Mode operation. The
relationship between the resistor value of external RT and the operating frequency is provided in the Figure
14. (page 7).
Rev. 1.30
3
March 25, 2016
HT7A6003
Typical Performance Characteristics
15.5
10
9.5
UVLO (off)(V)
UVLO (on)(V)
15
14.5
14
13.5
13
12.5
8
7.5
7
12
11.5
9
8.5
6.5
-40
-20
0
20
40
60
80
100
6
120
-40
10
Temperature (degree C)
Frequency (KHz)
Frequency (KHz)
-20
0
20
40
60
80
100
120
57
56
55
54
53
52
51
50
49
48
47
11
13
15
17
Temperature (degree C)
0
20
40
60
80
100
Vcomp (V)
23
25
31
29
27
25
23
21
19
17
15
11
120
Temperature (degree C)
13
15
17
19
21
23
25
Vcc (V)
Figure 6. Green Mode Frequency vs Vcc
Figure 5. Vcomp for SCP vs Temperature
Rev. 1.30
21
Figure 4. Frequency vs Vcc
Green Mode Frequency (KHz)
-20
19
Vcc (V)
Figure 3. Frequency vs Temperature
4.9
4.85
4.8
4.75
4.7
4.65
4.6
4.55
4.5
4.45
4.4
-40
110
Figure 2. UVLO (off)(V) vs Temperature
Figure 1. UVLO (on) (V) vs Temperature
57
56
55
54
53
52
51
50
49
48
47
-40
60
Temperature (degree C)
4
March 25, 2016
HT7A6003
Application Information
Full-Range (115V, 230V Vac) input, the Stand-by
Power will remain less than 0.3W@Pno=60W(as
shown in Table 2).This is within the Energy Star 5.0
criteria.
Operation Overview
The HT7A6003 is a highly function-integrated off-line
PWM Controller which is optimized for applications
that needs strong EMI-Restraining and various
abnormal conditions protecting capability. This
device has a wide operating temperature range (-40°C
to 85 °C), and provides many protection functions
such as Cycle-by-Cycle Current Limiting, SCP/
OLP, OVP, and Soft-Start function,, that ensure the
system implemented by HT7A6003 can operate very
stably at extreme environment like outdoor with ultra
low temperature (-40°C, the polar region), or high
EMI environment (factory or the region with highly
electromagnetic wave). The device is optimized for
the Energy Star 5.0 specification, this ensures that any
EPS (External Power Supply) implemented using the
HT7A6003 can fully satisfy the Energy Star 1.1/2.0
Stand-by (No-Load) criteria.
Demo Board
Input Condition
(Pno=60 watts)
0 to < 50 watts
≥ 50 to ≤ 250 watts
Stand-by Power
115V VAC
< 0.3W
230V VAC
< 0.3W
Table 2. Demo Board Stand-by Power Results
Advanced Precise-Oscillator for
Green-Mode Switching and Non-Acoustic
Noise Requirement
A Trimmed Precise Green Mode Oscillator is
implemented in the device to enhance the conversion
efficiency under conditions of light loads. As the
data shown in Fig. 8, the efficiency difference of the
traditional current mode PWM Controller between
light loads and heavy loads is more than 8%, while
the average efficiency is only 82%, the efficiency
difference of the HT7A6003 is only 1%, while
average efficiency is up to 87.5%.
Energy Consumption Criteria for No-Load
Nameplate Output
Power (Pno)
Input Range
Maximum Power in No-Load
AC-AC EPS
AC-DC EPS
≤ 0.5 watts
≤ 0.3 watts
≤ 0.5 watts
≤ 0.3 watts
Table 1: Energy Star 5.0 No-Load Criteria
Ultra Low Stand-by Power for Energy Star
5.0 and Later Energy Star Requirement
The device contains many advanced control schemes
for Low Stand-by Power like tiny Operating/Standby Current, Green Mode for Light-Load, etc. By
choosing an appropriate Stand-by resistor (as shown
in Fig. 7), EPS implemented by the device can fully
satisfy the Energy Star 5.0 No-Load criteria.
Figure 8. Efficiency Comparison between
HT7A6003 & Traditional Current Mode PWM
Figure 7. Stand-by Resistor
Controller (Measured at HT7A3942 Demo Board)
Base on device field test demo board results, for the
Rev. 1.30
5
March 25, 2016
HT7A6003
The Green Mode Oscillator types supplied by other
PWM Controller providers are plagued by the
problems of Acoustic-Noise. This is because, under
the conditions of light loads, the frequency will keep
decreasing through Human Acoustic Range (from
20Hz to 20KHz), these audio frequencies may create
audible noise in the transformer. Holtek’s HT7A6003
patented Green Mode Oscillator designed using an
advanced Non-Acoustic Noise Scheme to prevent
the generation of frequencies in the audio frequency
band, thus eliminating any transformer noise.
Start-up Current
(~uA)
Figure 10. UVLO Scheme and Start-Up Current
Current Sense and Leading-Edge
Blanking (LEB)
A Leading-Edge Blanking Scheme is integrated in
the device to prevent false triggering due to feedback
current spikes which may appear on the CS pin,
further eliminate the need for R-C filter which is
always a requirement in the traditional current mode
PWM Controller applications.
Figure 9. Oscillator Behavior Compared with
HT7A6003 and other Green Mode PWM Controller
Under Voltage Lockout (UVLO)
An UVLO comparator is implemented in to ensure
that the device is fully functional before the output
stage is enabled. As shown in Fig. 10, a hysteresis
is provided to prevent the PWM Controller from
shutting down during any voltage dips which might
occur during startup process. The turn-on and turnoff threshold levels are set at 14.0V and 8.0V,
respectively.
Rev. 1.30
Figure 11. LEB with R-C Filter Removed
6
March 25, 2016
HT7A6003
Internal Slope-Compensation
Over-Voltage Protection (OVP) on VCC Pin
An important issue with the current mode control
schemes is the instability due to Sub-Harmonic
Oscillation when the Duty-Cycle > 50%. To prevent
this problem from occurring, a Slope-Compensation
function is always necessary. In traditional current
mode PWM Controller application, many external
components are necessary for Slope-Compensation
function, but in HT7A6003 the internal SlopeCompensation eliminates the need for these external
components resulting in simplified the application
circuit design.
VCC Over-Voltage Protection is integrated in this
device to prevent components damage due to over
voltage condition on VCC pin. The OVP is triggered
when VCC reaches 28V and lasts for 80ms, and the
PWM pulses are disabled when OVP is enabled.
Frequency Jitter for EMI Restraining
EMI restraining is accomplished by Frequency Jitter
function, which spreads the energy over a wider
frequency range than the bandwidth measured by
the EMI test equipment. An internal Frequency Jitter
circuit changes the switching frequency between +4%
and -4% of central frequency with a period of 4ms.
Short-Circuit Protection (SCP) and
Over-Load Protection (OLP)
To protect all the devices of a system from being
damaged under over load or short circuit conditions,
a smart SCP function is implemented in the device.
Here the feedback system will force the voltage loop
to move toward a saturation value and then pull up
the voltage on the COMP pin. Whenever the VCOMP
increases to the SCP threshold of 4.7V and remains
there for longer than 40mS, the protection scheme
will activate and then turn off the gate output to
stop the switching of power circuit. By using such a
protection mechanism, the average input power can
be reduced to a very low level so that the component
temperature and stress can be controlled within safe
operating levels.
Figure 13. Frequency Jitter Function Spreads
Energy Over a Period to Accomplish EMI
Restraining
VCC
Oscillator Frequency Tuning
SCP
By choosing an appropriate value of an external
resistor between the RT Pin and GND, a suitable
operating frequency can be generated. It is necessary
that the operating frequency is set at 40~60kHz for
Green Mode operation. The relationship between the
value of RT and the operating frequency is provided
in the Figure 14.
UVLO(off)
SCP Reset
40ms
4.7V
SCP trip Level
Figure 12. SCP Function Behavior
Figure 14. RT Resistor value vs
Operating Frequency
Rev. 1.30
7
March 25, 2016
HT7A6003
Package Information
Note that the package information provided here is for consultation purposes only. As this information may be
updated at regular intervals users are reminded to consult the Holtek website for the latest version of the package
information.
Additional supplementary information with regard to packaging is listed below. Click on the relevant section to be
transferred to the relevant website page.
• Further Package Information (include Outline Dimensions, Product Tape and Reel Specifications)
• Packing Meterials Information
• Carton information
Rev. 1.30
8
March 25, 2016
HT7A6003
8-pin SOP (150mil) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
A
—
0.236 BSC
—
B
—
0.154 BSC
—
C
0.012
—
0.020
C′
—
0.193 BSC
—
0.069
D
—
—
E
—
0.050 BSC
—
F
0.004
—
0.010
G
0.016
—
0.050
H
0.004
—
0.010
α
0°
—
8°
Symbol
Rev. 1.30
Dimensions in mm
Min.
Nom.
Max.
—
A
—F
6.00 BSC
B
—
3.90 BSC
—
C
0.31
—
0.51
C′
—
4.90 BSC
—
D
—
—
1.75
E
—
1.27 BSC
—
F
0.10
—
0.25
G
0.40
—
1.27
H
0.10
—
0.25
α
0°
—
8°
9
March 25, 2016
HT7A6003
Copyright© 2016 by HOLTEK SEMICONDUCTOR INC.
The information appearing in this Data Sheet is believed to be accurate at the time
of publication. However, Holtek assumes no responsibility arising from the use of
the specifications described. The applications mentioned herein are used solely
for the purpose of illustration and Holtek makes no warranty or representation that
such applications will be suitable without further modification, nor recommends
the use of its products for application that may present a risk to human life due to
malfunction or otherwise. Holtek's products are not authorized for use as critical
components in life support devices or systems. Holtek reserves the right to alter
its products without prior notification. For the most up-to-date information, please
visit our web site at http://www.holtek.com.
Rev. 1.30
10
March 25, 2016