HM8119B [HMSEMI]
Standoff 55V 500mA 850KHz Sync Step-Down Regulator;
| 型号： | HM8119B |
| 厂家： | 
H&M Semiconductor |
| 描述： | Standoff 55V 500mA 850KHz Sync Step-Down Regulator |
| 文件： | 总13页 (文件大小：1892K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
HM8119
Standoff 55V 500mA 850KHz Sync Step-Down Regulator
Features
•
•
•
•
•
•
•
•
•
Wide 4.5V to 45V Operating Input Range
Standoff Voltage: 55V
•
500mΩ/300mΩ Low RDS(ON) Internal Power
MOSFETs
500mA Continuous Output Current
850KHz Switching Frequency
Short Protection with Foldback-Mode
Built-in Over Current Limit
•
•
•
•
•
•
Output Adjustable from 0.8/0.765/0.6V
No Schottky Diode Required
Integrated internal compensation
Thermal Shutdown
Built-in Over Voltage Protection
PSM Mode for High Efficiency in Light Load
Internal Soft-Start
Available in SOT23-6 Package
-40°C to +85°C Temperature Range
Applications
•
•
Battery-Powered Equipment
Portable Media Players
•
•
Industrial Distributed Power Applications
Portable Hand-Held Instruments
General Description
The HM8119 device is high-efficiency, synchronous step-down DC/DC regulators. With a wide input range, it is
suitable for a wide range of applications, such as power conditioning from unregulated sources. It features a low
RDSON (500mΩ/300mΩ typical) internal switch for maximum efficiency (92% typical). Supports PSM mode, the
operating frequency is fixed at 850kHz, allowing the use of small external components while still being able to have
low output voltage ripple. With OVP function, the IC can stand off input voltage as high as 55V. The HM8119
supports 600mA continuous output current, and it has a 0.8V nominal feedback voltage.
Additional features include: thermal shutdown, VIN undervoltage lockout, and gate drive undervoltage lockout. The
HM8119 is available in a low-profile SOT23-6 package.
Typical Application Circuit
C1
BS
L1
VOUT
VIN
IN
SW
FB
COUT
R1
CFF
ON/
OFF
CIN
EN
GND
R2
Basic Application Circuit
Page 1 / 13
HM8119
Standoff 55V 500mA 850KHz Sync Step-Down Regulator
Pin Description
Pin Configuration
TOP VIEW
BS
GND
FB
SW
IN
EN
SOT23-6
HM8119A Top Marking: HMYLL (device code: HM, Y=year code, LL= lot number code)
HM8119B Top Marking: HNYLL (device code: HN, Y=year code, LL= lot number code)
HM8119C Top Marking: HSYLL (device code: HS, Y=year code, LL= lot number code)
Pin Description
Pin
1
Name
BS
Function
Bootstrap. A capacitor connected between SW and BST pins is required to form a
floating supply across the high-side switch driver.
2
GND
FB
Ground Pin
Adjustable Version Feedback input. Connect FB to the center point of the external
resistor divider
3
Drive this pin to a logic-high to enable the IC. Drive to a logic-low to disable the
IC and enter micro-power shutdown mode.
4
EN
5
6
IN
Power Supply Pin
Switching Pin
SW
Order Information (1)
Marking
Part No.
Model
Description
Package
T/R Qty
HM8119 PSM SYN Buck, 4.5-45V,
0.5A, 850KHz, VFB 0.8V, SOT23-6
HMYLL
70301620
HM8119A
SOT23-6
3000PCS
HM8119 PSM SYN Buck, 4.5-45V,
0.5A, 850KHz, VFB 0.765V, SOT23-6
HNYLL
HSYLL
70301621
70301622
HM8119B
HM8119A
SOT23-6
SOT23-6
3000PCS
3000PCS
HM8119 PSM SYN Buck, 4.5-45V,
0.5A, 850KHz, VFB 0.6V, SOT23-6
Page 2 / 13
HM8119
Standoff 55V 500mA 850KHz Sync Step-Down Regulator
Specifications
Absolute Maximum Ratings (1) (2)
Item
Min
Max
55
55
55
7
Unit
V
VIN voltage
-0.3
EN voltage
–0.3 (VIN + 0.3 V)
-0.3
V
SW voltage
V
BS voltage
V
FB voltage
–0.3
6
V
Power dissipation (3)
Operating junction temperature, TJ
Storage temperature, Tstg
Lead Temperature (Soldering, 10sec.)
Internally Limited
-40
150
150
260
°C
°C
°C
–65
Note (1): Exceeding these ratings may damage the device.
Note (2): The device is not guaranteed to function outside of its operating conditions.
Note (3): The maximum allowable power dissipation is a function of the maximum junction temperature, TJ(MAX)
,
the junction-to-ambient thermal resistance, RθJA, and the ambient temperature, TA. The maximum allowable power
dissipation at any ambient temperature is calculated using: PD (MAX) = (TJ(MAX) − TA)/RθJA. Exceeding the maximum
allowable power dissipation causes excessive die temperature, and the regulator goes into thermal shutdown.
Internal thermal shutdown circuitry protects the device from permanent damage. Thermal shutdown engages at
TJ=150°C (typical) and disengages at TJ= 130°C (typical).
ESD Ratings
Item
Description
Value
Unit
Human Body Model (HBM)
ANSI/ESDA/JEDEC JS-001-2014
Classification, Class: 2
V(ESD-HBM)
±2000
V
Charged Device Mode (CDM)
ANSI/ESDA/JEDEC JS-002-2014
Classification, Class: C0b
JEDEC STANDARD NO.78E APRIL 2016
Temperature Classification,
Class: I
V(ESD-CDM)
±200
±150
V
ILATCH-UP
mA
Recommended Operating Conditions
Item
Min
–40
-40
4.5
0
Max
125
85
Unit
°C
°C
V
Operating junction temperature (1)
Operating temperature range
Input voltage VIN
45
Output current
0.5
A
Note (1): All limits specified at room temperature (TA = 25°C) unless otherwise specified. All room temperature
limits are 100% production tested. All limits at temperature extremes are ensured through correlation using standard
Page 3 / 13
HM8119
Standoff 55V 500mA 850KHz Sync Step-Down Regulator
Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL).
Thermal Information
Item
RθJA
RθJC(top)
RθJB
ψJT
Description
Value
105
55
Unit
Junction-to-ambient thermal resistance (1)(2)
Junction-to-case (top) thermal resistance
Junction-to-board thermal resistance
Junction-to-top characterization parameter
Junction-to-board characterization parameter
°C/W
°C/W
°C/W
°C/W
°C/W
17.5
3.5
ψJB
17.5
Note (1): The package thermal impedance is calculated in accordance to JESD 51-7.
Note (2): Thermal Resistances were simulated on a 4-layer, JEDEC board.
Electrical Characteristics (1) (2)
VIN=12V, TA=25°C, unless otherwise specified.
Parameter
Test Conditions
Min
Typ.
Max
45
Unit
V
Input Voltage Range
Supply Current (Quiescent)
Supply Current (Shutdown)
4.5
VEN =3.0V
0.4
0.8
mA
uA
V
VEN =0 or EN = GND
HM8119A
10
0.780
0.746
0.585
0.800
0.765
0.600
500
0.820
0.784
0.615
Feedback Voltage
HM8119B
V
HM8119C
V
High-Side Switch On-Resistance
Low-Side Switch On-Resistance
Valley Switch Current Limit
Over Voltage Protection Threshold
Switching Frequency
ISW=100mA
ISW=-100mA
mΩ
mΩ
A
300
1
48
850
89
V
KHz
%
Maximum Duty Cycle
VFB=90%
Minimum On-Time
83
nS
V
EN Rising Threshold
1.2
3.4
EN Falling Threshold
0.9
4.4
V
Wake up VIN Voltage
Shutdown VIN Voltage
Hysteresis VIN voltage
4.2
3.7
500
1
V
Under-Voltage Lockout Threshold
V
mV
mS
℃
℃
Soft Start
Thermal Shutdown
Thermal Hysteresis
150
30
Note (1): MOSFET on-resistance specifications are guaranteed by correlation to wafer level measurements.
Note (2): Thermal shutdown specifications are guaranteed by correlation to the design and characteristics analysis.
Page 4 / 13
HM8119
Standoff 55V 500mA 850KHz Sync Step-Down Regulator
Typical Performance Characteristics (1) (2)
Note (1): Performance waveforms are tested on the evaluation board.
Note (2): VIN =12V, VOUT=3.3V, TA = +25ºC, unless otherwise noted.
Efficiency vs Load Current
Load Regulation
Line Regulation
VOUT=5V, 3.3V, 1.2V
VOUT=5V, 3.3V, 1.2
VOUT=3.3V
Output Ripple Voltage
Output Ripple Voltage
Output Ripple Voltage
VIN=12V, VOUT=3.3V, IOUT=0mA
VIN=12V, VOUT=3.3V, IOUT=250mA
VIN=12V, VOUT=3.3V, IOUT=500mA
Loop Response
Output Short
Short Circuit Entry
VIN=12V, VOUT=3.3V, IOUT=100mA-500mA
VIN=12V, VOUT=3.3V
VIN=12V, VOUT=3.3V
Page 5 / 13
HM8119
Standoff 55V 500mA 850KHz Sync Step-Down Regulator
Short Circuit Recovery
Enable Startup at No Load
Enable Shutdown at No Load
VIN=12V, VOUT=3.3V
VIN=12V, VOUT=3.3V, IOUT=0mA
VIN=12V, VOUT=3.3V, IOUT=0mA
Enable Startup at Full Load
Enable Shutdown at Full Load
Power Up at No Load
VIN=12V, VOUT=3.3V, IOUT=500mA
VIN=12V, VOUT=3.3V, IOUT=500mA
VIN=12V, VOUT=3.3V, IOUT=0mA
Power Up at Full Load
VIN=12V, VOUT=3.3V, IOUT=500mA
Page 6 / 13
HM8119
Standoff 55V 500mA 850KHz Sync Step-Down Regulator
Functional Block Diagram
IN
Peak Curve
Detection
Regulator
BS
Bias&Ref
EN
0.8/2MHz
Clock
Slope
Compensation
Driver
SW
Comparator
Error Amplifier
FB
Fault
Detection
Valley Curve
Detection
GND
OTP
Block Diagram
Functions Description
Internal Regulator
The HM8119 is a current mode step down DC/DC converter that provides excellent transient response with no extra
external compensation components. This device contains an internal, low resistance, high voltage power MOSFET,
and operates at a high 850KHz operating frequency to ensure a compact, high efficiency design with excellent AC
and DC performance.
Under-Voltage Lockout (UVLO)
Under-voltage lockout (UVLO) protects the chip from operating at an insufficient supply voltage. UVLO protection
monitors the internal regulator voltage. When the voltage is lower than UVLO threshold voltage, the device is shut
off. When the voltage is higher than UVLO threshold voltage, the device is enabled again.
Thermal Shutdown
Thermal shutdown prevents the chip from operating at exceedingly high temperatures. When the silicon die
temperature exceeds 150°C, it shuts down the whole chip. When the temperature falls below its lower threshold
(Typ. 130°C) the chip is enabled again.
Internal Soft-Start
The soft-start is implemented to prevent the converter output voltage from overshooting during startup. When the
chip starts, the internal circuitry generates a soft-start voltage (SS) ramping up from 0V to VFB. When it is lower
than the internal reference (REF), SS overrides REF so the error amplifier uses SS as the reference. When SS is
higher than REF, REF regains control. The SS time is internally max to 1ms.
Page 7 / 13
HM8119
Standoff 55V 500mA 850KHz Sync Step-Down Regulator
Over Current Protection
The HM8119 has cycle-by-cycle over current limit when the inductor current peak value exceeds the set current
limit threshold. Meanwhile, output voltage starts to drop until FB is below the Under-Voltage (UV) threshold. Once
a UV is triggered, the HM8119 enters hiccup mode to periodically restart the part. This protection mode is especially
useful when the output is dead-short to ground. The average short circuit current is greatly reduced to alleviate the
thermal issue and to protect the regulator. The HM8119 exits the foldback mode once the over current condition is
removed.
Startup and Shutdown
If both VIN and EN are higher than their appropriate thresholds, the chip starts. The reference block starts first,
generating stable reference voltage and currents, and then the internal regulator is enabled. The regulator provides
stable supply for the remaining circuitries. Three events can shut down the chip: EN low, VIN low and thermal
shutdown. In the shutdown procedure, the signaling path is first blocked to avoid any fault triggering. The comp
voltage and the internal supply rail are then pulled down. The floating driver is not subject to this shutdown
command.
Page 8 / 13
HM8119
Standoff 55V 500mA 850KHz Sync Step-Down Regulator
Applications Information
Setting the Output Voltage
HM8119 require an input capacitor, an output capacitor, and an inductor. These components are critical to the
performance of the device. HM8119 integrates internal loop compensating resistors, so we do not recommend using
a value of more than 50K for R1. The output voltage can be programmed by resistor divider.
푅1 + 푅2
푉푂푈푇 = 푉퐹퐵
×
푅2
Example for VFB=0.8V
VOUT(V)
1.0
R1(KΩ)
51
R2(KΩ)
204
L1(μH)
1.0
C1(nF)
100
CIN(μF)
22
COUT(μF)
22×2
CFF (pF) Opt.
CFF Chapter
CFF Chapter
CFF Chapter
CFF Chapter
CFF Chapter
CFF Chapter
CFF Chapter
1.2
51
102
1.5
100
22
22×2
1.5
51
58.29
40.8
2.2
100
22
22×2
1.8
51
2.2
100
22
22×2
2.5
51
24
2.2
100
22
22×2
3.3
51
16.32
9.71
3.3
100
22
22×2
5.0
51
4.7
100
22
22×2
All the external components are the suggested values, the final values are based on the application testing results.
Selecting the Inductor
The recommended inductor values are shown in the Application Diagram. It is important to guarantee the inductor
core does not saturate during any foreseeable operational situation. The inductor should be rated to handle the
maximum inductor peak current: Care should be taken when reviewing the different saturation current ratings that
are specified by different manufacturers. Saturation current ratings are typically specified at 25°C, so ratings at
maximum ambient temperature of the application should be requested from the manufacturer. The inductor value
can be calculated with:
(
)
푉푂푈푇 × 푉퐼푁 − 푉푂푈푇
퐿 =
푉
퐼푁 × ∆ꢀꢁ × ꢂ푂푆퐶
Where ΔIL is the inductor ripple current. Choose inductor ripple current to be approximately 30% to 40% of the
maximum load current. The maximum inductor peak current can be estimated as:
∆ꢀꢁ
ꢀꢁ(푀퐴푋) = ꢀꢁ푂퐴퐷
+
2
Under light load conditions below 100mA, larger inductance is recommended for improved efficiency. Larger
inductances lead to smaller ripple currents and voltages, but they also have larger physical dimensions, lower
saturation currents and higher linear impedance. Therefore, the choice of inductance should be compromised
according to the specific application.
Page 9 / 13
HM8119
Standoff 55V 500mA 850KHz Sync Step-Down Regulator
Selecting the Input Capacitor
The input current to the step-down converter is discontinuous and therefore requires a capacitor to supply AC current
to the step-down converter while maintaining the DC input voltage. For a better performance, use ceramic capacitors
placed as close to VIN as possible and a 0.1µF input capacitor to filter out high frequency interference is
recommended. Capacitors with X5R and X7R ceramic dielectrics are recommended because they are stable with
temperature fluctuations.
The capacitors must also have a ripple current rating greater than the maximum input ripple current of the converter.
The input ripple current can be estimated with Equation:
푉푂푈푇
푉푂푈푇
ꢀ퐶퐼푁 = ꢀ푂푈푇 × √
× ꢃ1 −
ꢄ
푉
퐼푁
푉
퐼푁
From the above equation, it can be concluded that the input ripple current reaches its maximum at VIN=2VOUT where
퐼
I퐶퐼푁
=
ꢅꢆꢇ. For simplification, choose an input capacitor with an RMS current rating greater than half of the
ꢈ
maximum load current.
The input capacitance value determines the input voltage ripple of the converter. If there is an input voltage ripple
requirement in the system, choose the input capacitor that meets the specification. The input voltage ripple can be
estimate with Equation:
ꢀ푂푈푇
푉푂푈푇
푉푂푈푇
∆푉
=
×
× ꢃ1 −
ꢄ
퐼푁
ꢂ푂푆퐶 × ꢉ퐼푁
푉
퐼푁
푉
퐼푁
ꢊ
4
퐼
ꢅꢆꢇ
Similarly, when VIN=2VOUT, input voltage ripple reaches its maximum of ∆푉
=
×
.
×퐶
ꢍꢎ
퐼푁
퐹
ꢅꢋꢌ
Selecting the Output Capacitor
An output capacitor is required to maintain the DC output voltage. The output voltage ripple can be estimated with
Equation:
푉푂푈푇
푉푂푈푇
1
∆푉푂푈푇
=
× ꢃ1 −
ꢄ × ꢃ푅퐸푆ꢏ
+
ꢄ
ꢂ푂푆퐶 × 퐿
푉
퐼푁
8 × ꢂ푂푆퐶 × ꢉ푂푈푇
There are some differences between different types of capacitors. In the case of ceramic capacitors, the impedance
at the switching frequency is dominated by the capacitance. The output voltage ripple is mainly caused by the
capacitance. For simplification, the output voltage ripple can be estimated with Equation:
푉푂푈푇
푉푂푈푇
∆푉푂푈푇
=
× ꢃ1 −
ꢄ
8 × ꢂ푂푆퐶ꢈ × 퐿 × ꢉ푂푈푇
푉
퐼푁
A larger output capacitor can achieve a better load transient response, but the maximum output capacitor limitation
should also be considered in the design application. If the output capacitor value is too high, the output voltage will
not be able to reach the design value during the soft-start time and will fail to regulate. The maximum output
capacitor value (COUT
_
MAX) can be limited approximately with Equation:
ꢉ푂푈푇_푀퐴푋 = ꢐꢀꢁ퐼푀_퐴ꢑ퐺 − ꢀ푂푈푇ꢒ × ꢓ /푉푂푈푇
푆푆
Page 10 / 13
HM8119
Standoff 55V 500mA 850KHz Sync Step-Down Regulator
Where LLIM_AVG is the average start-up current during the soft-start period, and TSS is the soft- start time.
On the other hand, special attention should be paid when selecting these components. The DC bias of these
capacitors can result in a capacitance value that falls below the minimum value given in the recommended capacitor
specifications table.
The ceramic capacitor’s actual capacitance can vary with temperature. The capacitor type X7R, which operates over
a temperature range of −55°C to +125°C, will only vary the capacitance to within ±15%. The capacitor type X5R
has a similar tolerance over a reduced temperature range of −55°C to +85°C. Many large value ceramic capacitors,
larger than 1uF are manufactured with Z5U or Y5V temperature characteristics. Their capacitance can drop by more
than 50% as the temperature varies from 25°C to 85°C. Therefore, X5R or X7R is recommended over Z5U and
Y5V in applications where the ambient temperature will change significantly above or below 25°C.
Feed-Forward Capacitor (CFF)
HM8119 has internal loop compensation, so adding CFF is optional. Specifically, for specific applications, if
necessary, consider whether to add feed-forward capacitors according to the situation.
The use of a feed-forward capacitor (CFF) in the feedback network is to improve the transient response or higher
phase margin. For optimizing the feed-forward capacitor, knowing the cross frequency is the first thing. The cross
frequency (or the converter bandwidth) can be determined by using a network analyzer. When getting the cross
frequency with no feed-forward capacitor identified, the value of feed-forward capacitor (CFF) can be calculated
with the following Equation:
1
1
1
1
√
ꢉ퐹퐹
=
×
× ꢃ
+
ꢄ
2휋 × ꢂ퐶ꢏ푂푆푆
푅1
푅1 푅2
Where FCROSS is the cross frequency.
To reduce transient ripple, the feed-forward capacitor value can be increased to push the cross frequency to higher
region. Although this can improve transient response, it also decreases phase margin and cause more ringing. In the
other hand, if more phase margin is desired, the feed-forward capacitor value can be decreased to push the cross
frequency to lower region.
Page 11 / 13
HM8119
Standoff 55V 500mA 850KHz Sync Step-Down Regulator
PC Board Layout Consideration
PCB layout is very important to achieve stable operation. It is highly recommended to duplicate EVB layout for
optimum performance. If change is necessary, please follow these guidelines for reference.
1. Keep the path of switching current short and minimize the loop area formed by Input capacitor, high-side
MOSFET and low-side MOSFET.
2. Bypass ceramic capacitors are suggested to be put close to the VIN Pin.
3. Ensure all feedback connections are short and direct. Place the feedback resistors and compensation
components as close to the chip as possible.
4. VOUT, SW away from sensitive analog areas such as FB.
5. Connect IN, SW, and especially GND respectively to a large copper area to cool the chip to improve thermal
performance and long-term reliability.
Top Layer
Bottom Layer
Sample Board Layout
Page 12 / 13
HM8119
Standoff 55V 500mA 850KHz Sync Step-Down Regulator
Package Description
SOT23-6
0.95
BSC
2.80
3.00
0.60
TYP
1.20
TYP
EXAMPLE
TOP MARK
1.50
1.70
2.60
3.00
2.60
TYP
AAAAA
PIN 1
TOP VIEW
RECOMMENDED PAD LAYOUT
GAUGE PLANE
0.25 BSC
0.90
1.30
1.45 MAX
SEATING PLANE
0.30
0.50
0.00
0.15
0.09
0.20
0.30
0.55
0.95 BSC
0°~8°
FRONT VIEW
SIDE VIEW
NOTE:
1. CONTROL DIMENSION IS IN INCHES. DIMENSION IN BRACKET IS IN MILLIMETERS.
2. PACKAGE LENGTH DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS.
3. PACKAGE WIDTH DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS.
4. LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.004" INCHES MAX.
5. DRAWING CONFORMS TO JEDEC MS-012, VARIATION BA.
6. DRAWING IS NOT TO SCALE.
Page 13 / 13
相关型号：
HM82173-A1F
Rectangular Power Connector, 144 Contact(s), Female, Press Fit Terminal, LEAD FREE
FOXCONN
HM82193-A14F
Rectangular Power Connector, 32 Contact(s), Male, Press Fit Terminal, LEAD FREE
FOXCONN
©2020 ICPDF网 联系我们和版权申明