SUTEX HV9967BMG-G Integrated led driver with average-mode current control Datasheet

Supertex inc.
HV9967B
Integrated LED Driver
with Average-Mode Current Control
Features
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General Description
3% accurate LED current
Integrated 60V, 0.8Ω MOSFET
Low sensitivity to external component variation
Single resistor LED current setting
Fixed off-time control
PWM dimming input
Output short circuit protection with skip mode
Over-temperature protection
Available in compact 8-Lead MSOP and 8-Lead
DFN packages
The HV9967B is an average-mode current control LED driver IC
operating in a constant off-time mode.
The IC features an integrated 60V, 0.8Ω MOSFET that can be
used as a stand-alone buck converter switch, or connected as a
source driver for driving an external high-voltage depletion-mode
MOSFET. The HV9967B is powered through its switching output
when the integrated switch is off. Hence, the same external
MOSFET can be used as a high-voltage linear regulator for
powering the IC.
The LED current is programmed with one external resistor. The
average-mode current control method does not produce a peakto-average error, and therefore greatly improves current accuracy
and line and load regulation of the LED current without any need
for loop compensation or direct sensing of the LED current at a
high-voltage potential. The auto-zero circuit cancels the effects of
the input offset voltage and of the propagation delay of the current
sense comparator.
Applications
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DC/DC or AC/DC LED drivers
RGB backlighting drivers for flat panel displays
General purpose constant current source
Signage and decorative LED lighting
Chargers
Typical Application Circuit
8.0 - 60VDC
+
CO
D1
CIN
LED
String
U1
4
2
RSENSE
SW
PWMD
HV9967B
RSENSE
PGND AGND
3
7
VDD
RT
1
L1
8
6
CDD
RT
Doc.# DSFP-HV9967B
B060712
Supertex inc.
www.supertex.com
HV9967B
Pin Configurations
Ordering Information
Part Number
Package Options
Packing
HV9967BK7-G
8-Lead DFN (3x3mm)
3000/Reel
RSENSE 2
HV9967BMG-G
8-Lead MSOP
2500/Reel
PGND 3
SW 1
GND
PWMD 4
-G indicates package is RoHS compliant (‘Green’)
8
VDD
7
AGND
6
RT
5
NC
8-Lead DFN (K7)
(top view)
Absolute Maximum Ratings*
Parameter
Value
SW to GND
-0.5V to +65V
VDD to GND
-0.3V to 6.0V
Other I/O to GND
-0.3V to (VDD + 0.3V)
RT, ISET
2.0mA
Continuous power dissipation (TA = +25°C)
8-Lead DFN (K7)
8-Lead MSOP (MG)
-40°C to +150°C
Storage temperature range
-65°C to +150°C
8-Lead DFN
37OC/W
8-Lead MSOP
216 C/W
RSENSE 2
7
AGND
PGND 3
6
RT
PWMD 4
5
NC
Product Marking
Y = Last Digit of Year Sealed
W = Code for Week Sealed
L = Lot Number
= “Green” Packaging
H6 7 B
YWLL
Package may or may not include the following marks: Si or
8-Lead DFN (K7)
Top Marking
967B
LLLL
Typical Thermal Resistance
θja
VDD
(top view)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause
permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in
the operational sections of the specifications is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
Package
8
8-Lead MSOP (MG)
1.6W
350mW
Junction temperature
SW 1
Bottom Marking
YYWW
L = Lot Number
YY = Year Sealed
WW = Week Sealed
= “Green” Packaging
O
Package may or may not include the following marks: Si or
8-Lead MSOP (MG)
Electrical Characteristics
(The * denotes specifications which apply over the full operating ambient temperature range of -40°C < TA < 125°C. Otherwise specifications are at TA =
25°C. VSW = 10V/10mA, VDD = 5.0V unless otherwise noted)
Sym
Description
Min
Typ
Max
Units
Conditions
Input
VSWDC
IINSD
Input DC supply voltage range
*
8.0
-
60
V
Shut-down mode supply current
-
-
0.5
1.0
mA
DC input voltage
Pin PWMD to GND
Notes:
#
Not production tested; guaranteed by design or characterization.
*
Specifications apply over the full operating ambient temperature range of -40°C < TA < +125°C.
Doc.# DSFP-HV9967B
B060712
2
Supertex inc.
www.supertex.com
HV9967B
Electrical Characteristics (cont.)
(The * denotes specifications which apply over the full operating ambient temperature range of -40°C < TA < 125°C. Otherwise specifications are at TA =
25°C. VSW = 10V/10mA, VDD = 5.0V unless otherwise noted)
Sym
Description
Min
Typ
Max
Units
Conditions
Internal Regulator
VDD
Internally regulated voltage
-
4.70
5.00
5.20
V
PWMD = VDD; RT = 100kΩ
UVLO
VDD undervoltage lockout threshold
*
4.10
-
4.70
V
VDD rising, as needed to
ensure IC(MIN)
ΔUVLO
VDD undervoltage lockout hysteresis
-
-
150
-
mV
VDD falling
PWM Dimming
VEN(LO)
PWMD input low voltage
*
-
-
0.8
V
---
VEN(HI)
PWMD input high voltage
*
2.0
-
-
V
---
Internal pull down resistance at PWMD
-
50
100
150
kΩ
VPWMD = 5.0V
---
REN
Current Control
VCS(TH)
RSENSE current threshold
-
243
-
257
mV
dVCS/dt
Temperature regulation
-
-
0.1
-
mV/ C
TBLANK
Current sense blanking interval
*
140
-
290
ns
---
TON(MIN)
Minimum ON-time
*
-
-
950
ns
VRSENSE = VCS(TH) + 50mV
Reduction in output LED
current occurs beyond this
duty cycle due to saturation
of T2 timers.
O
*
80
-
-
%
Hiccup threshold voltage at RSENSE
*
355
-
440
mV
---
TDELAY
Current limit delay RSENSE to SW-OFF
-
-
-
150
ns
VRSENSE = VCS(SHORT) + 50mV
THICCUP
Hiccup time
-
-
800
-
μs
---
TON(MIN)
Minimum ON-time (short circuit)
-
-
-
400
ns
VRSENSE = VCS(SHORT) + 50mV
28
40
48
7.0
10
12
0.7
1.0
1.2
DMAX
Maximum steady-state duty cycle
O
Short Circuit Protection
VCS(SHORT)
TOFF Timer
TOFF
OFF time
*
RT = 400kΩ
μs
RT = 100kΩ
RT = 10kΩ
SW Output
RON
IC
ON resistance
-
-
0.8
-
Ω
VDD = 5.0V
Continuous current
*
0.75
-
-
A
VDD = 4.75V,
VRSENSE = 370mV, VSW =10V
Shut-down temperature
#
125
-
-
O
C
---
Hysteresis
#
-
20
-
O
C
---
Over-temperature Protection
TSD
ΔTSD
Notes:
#
Not production tested; guaranteed by design or characterization.
*
Specifications apply over the full operating ambient temperature range of -40°C < TA < +125°C.
Doc.# DSFP-HV9967B
B060712
3
Supertex inc.
www.supertex.com
HV9967B
Functional Block Diagram
VDD
HV9967B
4.35V
UVLO
VCS
REG
POR
L/E
Blanking
IN
SW
Average
Current
Control Logic
OTP
RSENSE
VCS
OUT
RQ
0.4V
PGND
S Q
SET
PWMD
100kΩ
PGND
TOFF
Timer
AGND
i
0.8ms
RT
Application Information
Average Current Control Feedback and Output
Short Circuit Protection
General description
The HV9967B employs Supertex’ proprietary control scheme,
achieving fast and very accurate control of average current
in the buck inductor through sensing the switch current only.
No compensation of the current control loop is required. The
LED current response to PWMD input is similar to that of the
peak-current control ICs, such as HV9910B. The inductor
current ripple amplitude does not affect this control scheme
significantly, and therefore, the LED current is independent
of the variation in inductance, switching frequency or output
voltage. Constant off-time control of the buck converter is
used for stability and to reduce input voltage regulation of
the LED current.
The constant-current control feedback derives the average current signal from the source current of the switching
MOSFET. This current is detected using a sense resistor at
the RSENSE pin. The feedback operates in a fast open-loop
mode. No compensation is required. Output current is programmed simply as:
ILED =
(2)
VO(MAX) • TOFF
LO =
(3)
0.4 • IO
The duty-cycle range of the current control feedback is limited to D ≤ 0.8. A reduction in the LED current may occur
when the LED string voltage VO is greater than 80% of the
input voltage VIN of the HV9967B LED driver.
(1)
within the range of 10kΩ ≤ RT ≤ 400kΩ.
Doc.# DSFP-HV9967B
B060712
The above equation is only valid for continuous conduction
of the output inductor. It is a good practice to design the inductor such that the switching ripple current in it is 30~40%
of its average full load DC current peak-to-peak. Hence, the
recommended inductance can be calculated as:
OFF Timer
The timing resistor connected to RT determines the off-time
of the gate driver, and it must be wired to VDD. The equation
governing the off-time of the GATE output is given by:
TOFF = RT • 100pF
0.25V
RCS
4
Supertex inc.
www.supertex.com
HV9967B
Reducing the output LED voltage VO below VO(MIN) = VIN • DMIN,
where DMIN = 0.8µs/(TOFF + 0.8µs), may also result in the loss
of regulation of the LED current. This condition, however,
causes increase in the LED current and can potentially trip
the short-circuit protection comparator threshold.
SW Input and Linear Regulator
The short circuit protection comparator trips when the voltage at RSENSE exceeds 0.4V. When this occurs, the SW
off-time THICCUP = 800µs is generated to prevent stair-casing
of the inductor current and potentially its saturation due to
insufficient output voltage. The typical short-circuit current is
shown in the waveform of Fig. 1.
PWM Dimming
HV9967B includes an integrated 60V, 0.8Ω switching
MOSFET at the SW input. The power for the IC is supplied
from a linear 5.0V regulator that is also derived from the SW
input.
The HV9967B features a TTL compatible dimming input
PWMD. Applying a square-wave voltage to PWMD will modulate the duty ratio of the LED current accordingly. The rising
and falling edges are limited by the current slew rate in the
inductor. The first switching cycle is terminated upon reaching the 250mV level at RSENSE. The circuit will reach the
steady state within 3~4 switching cycles regardless of the
switching frequency.
0.44V/RSENSE
800µs
Over-Temperature Protection
The HV9967B includes over-temperature protection. Typically, when the junction temperature exceeds 145OC, switching of the SW input is disabled. The switching resumes when
the temperature falls by approximately 20OC from the trip
point.
Fig.1. Short-circuit inductor current.
A leading-edge blanking delay is provided at RSENSE to
prevent false triggering of the current feedback and the short
circuit protection.
Pin Description
Pin #
Function
1
SW
2
RSENSE
3
PGND
Power ground. Must be wired to AGND on PCB.
4
PWMD
PWM dimming input. This TTL input enables switching of SW when in high state.
5
NC
No connection.
6
RT
Resistor connected between RT and VDD programs the off-time of SW.
7
AGND
8
VDD
Doc.# DSFP-HV9967B
B060712
Description
Drain of 60V 0.8Ω NDMOS switch and input of H/V regulator.
Source of NDMOS switch and current sense input.
Connect a resistor to GND to program the output current and short circuit thresholds.
Analog ground (0V).
Power supply for all internal circuits. Bypass with a low ESR capacitor to PGND (>0.5μF).
Connect GATE of external depletion-mode NFET for high-voltage operation.
5
Supertex inc.
www.supertex.com
HV9967B
8-Lead DFN Package Outline (K7)
3.00x3.00mm body, 0.80mm height (max), 0.65mm pitch
D2
D
8
8
E
E2
Note 1
(Index Area
D/2 x E/2)
Note 1
(Index Area
D/2 x E/2)
1
1
Top View
Bottom View
View B
Note 3
θ
A
A3
e
b
A1
L
Seating
Plane
L1
Note 2
View B
Side View
Notes:
1. A Pin 1 identifier must be located in the index area indicated. The Pin 1 identifier can be: a molded mark/identifier; an embedded metal marker; or
a printed indicator.
2. Depending on the method of manufacturing, a maximum of 0.15mm pullback (L1) may be present.
3. The inner tip of the lead may be either rounded or square.
Symbol
Dimension
(mm)
A
A1
MIN
0.70
0.00
NOM
0.75
0.02
MAX
0.80
0.05
A3
0.20
REF
b
D
D2
E
E2
0.25
2.85*
1.60
2.85*
1.35
0.30
3.00
-
3.00
-
0.35
3.15*
2.50
3.15*
1.75
e
0.65
BSC
L
L1
θ
0.30
0.00*
0O
0.40
-
-
0.50
0.15
14O
JEDEC Registration MO-229, Variation WEEC-2, Issue C, Aug. 2003.
* This dimension is not specified in the JEDEC drawing.
Drawings not to scale.
Supertex Doc. #: DSPD-8DFNK73X3P065, Version C081109.
Doc.# DSFP-HV9967B
B060712
6
Supertex inc.
www.supertex.com
HV9967B
8-Lead MSOP Package Outline (MG)
3.00x3.00mm body, 1.10mm height (max), 0.65mm pitch
D
θ1 (x4)
8
E
E1
Gauge
Plane
L2
Note 1
(Index Area
D/2 x E1/2)
L
1
L1
Top View
A
Seating
Plane
θ
View B
View B
A A2
Seating
Plane
b
e
A1
View A-A
Side View
A
Note:
1. A Pin 1 identifier must be located in the index area indicated. The Pin 1 identifier can be: a molded mark/identifier; an embedded metal marker; or
a printed indicator.
Symbol
Dimension
(mm)
A
A1
A2
b
D
E
E1
MIN
0.75*
0.00
0.75
0.22
2.80*
4.65*
2.80*
NOM
-
-
0.85
-
3.00
4.90
3.00
MAX
1.10
0.15
0.95
0.38
3.20*
5.15*
3.20*
e
0.65
BSC
L
0.40
0.60
0.80
L1
L2
0.95
REF
0.25
BSC
θ
θ1
0O
5O
-
-
8O
15O
JEDEC Registration MO-187, Variation AA, Issue E, Dec. 2004.
* This dimension is not specified in the JEDEC drawing.
Drawings are not to scale.
Supertex Doc. #: DSPD-8MSOPMG, Version H041309.
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline
information go to http://www.supertex.com/packaging.html.)
Supertex inc. does not recommend the use of its products in life support applications, and will not knowingly sell them for use in such applications unless it receives
an adequate “product liability indemnification insurance agreement.” Supertex inc. does not assume responsibility for use of devices described, and limits its liability
to the replacement of the devices determined defective due to workmanship. No responsibility is assumed for possible omissions and inaccuracies. Circuitry and
specifications are subject to change without notice. For the latest product specifications refer to the Supertex inc. (website: http//www.supertex.com)
Supertex inc.
©2012 Supertex inc. All rights reserved. Unauthorized use or reproduction is prohibited.
Doc.# DSFP-HV9967B
B060712
7
1235 Bordeaux Drive, Sunnyvale, CA 94089
Tel: 408-222-8888
www.supertex.com
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