SUPERTEX HV9112NG-G

HV9112
High-Voltage Current-Mode PWM Controller
General Description
Features
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The Supertex HV9112 is a BiCMOS/DMOS single-output,
pulse width modulator IC intended for use in high-speed,
high-efficiency switch mode power supplies. It provides all the
functions necessary to implement a single-switch current mode
PWM, in any topology, with a minimum of external parts.
10V to 120V Input Voltage Range
Current-mode control
High efficiency
Up to 1.0MHz internal oscillator
Internal start-up circuit
Low internal noise
Because the HV9112 utilizes Supertex’s proprietary BiCMOS/
DMOS technology, it requires less than one tenth of the operating
power of conventional bipolar PWM ICs, and can operate at
more than twice their switching frequency. The dynamic range
for regulation is also increased, to approximately 8 times that
of similar bipolar parts. It starts directly from any DC input
voltage between 10 and 120VDC, requiring no external power
resistor. The output stage is push-pull CMOS and thus requires
no clamping diodes for protection, even when significant lead
length exists between the output and the external MOSFET. The
clock frequency is set with a single external resistor.
Applications
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DC/DC converters
Distributed power systems
ISDN equipment
PBX systems
Modems
Accessory functions are included to permit fast remote shutdown
(latching or nonlatching) and under voltage shutdown.
Ordering Information
Device
Package Option
14-Lead Narrow Body SOIC (NG)
HV9112
HV9112NG-G
For similar ICs intended to operate directly from up to 450VDC
input, please consult the data sheets for the HV9120 and
HV9123.
For detailed circuit and application information, please refer to
application notes AN-H13 and AN-H21 to AN-H24.
-G indicates package is RoHS compliant (‘Green’)
Pin Configuration
OSC IN
DISCHARGE
VREF
SHUTDOWN
RESET
COMP
FB
Absolute Maximum Ratings
OSC OUT
Parameter
Input voltage, VIN
Logic voltage, VDD
Logic linear input,
FB and sense input voltage
Storage temperature
VDD
Value
-VIN
OUTPUT
SENSE
80V
15.5V
+VIN
BIAS
14-Lead Narrow Body SOIC (NG)
-0.3V to VDD +0.3V
-65°C to +150°C
Product Marking
Top Marking
Power dissipation
750mW
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.
HV9112NG
YWW
LLLLLLLL
Bottom Marking
CCCCCCCCC AAA
Y = Last Digit of Year Sealed
WW = Week Sealed
L = Lot Number
C = Country of Origin*
A = Assembler ID*
= “Green” Packaging
*May be part of top marking
14-Lead Narrow Body SOIC (NG)
HV9112
Electrical Characteristics
(Unless otherwise specified, VDD = 10V, +VIN = 48V, Discharge = -VIN = 0V, RBIAS = 390KΩ, ROSC = 330KΩ, TA = 25°C.)
Sym
Parameter
#
Min
Typ
Max
Units
Conditions
VREF
Output voltage
-
3.88
4.00
4.12
V
RL = 10MΩ
ZOUT
Output impedence
#
15
30
45
KΩ
---
ISHORT
Short circuit current
-
-
125
250
μA
VREF = -VIN
ΔVREF
Change in VREF with temperature
#
-
0.25
-
mV/°C
fMAX
Oscillator frequency
-
1.0
3.0
-
MHz
fOSC
Initial accuracy(1)
-
80
100
120
-
160
200
240
-
Voltage stability
-
-
-
15
%
-
Temperature coefficient
#
-
170
-
ppm/°C
Maximum duty cycle
-
49.0
49.4
49.6
%
---
Deadtime
#
-
-
-
ns
---
Minimum duty cycle
-
-
-
0
%
---
Maximum pulse width before pulse
drops out
#
-
80
125
ns
---
Maximum input signal
-
1.0
1.2
1.4
V
VFB = 0V
Delay to output
#
-
80
120
ns
VSENSE = 1.5V,
VCOMP ≤ 2.0V
Reference
TA = -55°C to 125°C
Oscillator
PWM
DMAX
DMIN
KHz
ROSC = 1.0MΩ
ROSC = 330KΩ
ROSC = 150KΩ
VSYNC = 0.1V
TA = -55°C to 125°C
Current Limit
tD
Error Amplifier
VFB
Feedback voltage
-
3.92
4.00
4.08
V
VFB shorted to comp
IIN
Input bias current
-
-
25
500
nA
VFB = 4.0V
VOS
Input offset voltage
-
nulled during trim
AVOL
Open loop voltage gain
#
60
80
GB
Unity gain bandwidth
#
1.0
1.3
ZOUT
Out impedance
#
Output source current
-
-1.4
-2.0
-
mA
VFB = 3.4V
Output sink current
-
0.12
0.15
-
mA
VFB = 4.5V
Power supply rejection
#
dB
---
ISOURCE
ISINK
PSRR
-
---
-
dB
---
-
MHz
---
Ω
---
see Fig. 1
see Fig. 2
Notes:
# Guaranteed by design. Not subject to production test.
(1) Stray capacitance on OSC In pin must be ≤5pF.
2
HV9112
Electrical Characteristics (cont.)
(Unless otherwise specified, VDD = 10V, +VIN = 48V, Discharge = -VIN = 0V, RBIAS = 390KΩ, ROSC = 330KΩ, TA = 25°C.)
Sym
Parameter
#
Min
Typ
Max
Units
Conditions
Pre-regulator/Startup
+VIN
Input voltage
-
9.0
-
80
V
IIN < 10µA; VCC > 9.4V
+IIN
Input leakage current
-
-
-
10
μA
VDD > 9.4V
VTH
Vdd pre-regulator turn-off threshold
voltage
-
8.0
8.7
9.4
V
IPREREG = 10µA
Undervoltage lockout
-
7.0
8.1
8.9
V
---
IDD
Supply current
-
-
0.75
1.0
mA
CL < 75pF
IQ
Quiescent supply current
-
-
0.55
-
mA
Shutdown = -VIN
IBIAS
Nominal Bias current
-
-
20
-
μA
---
VDD
Operating range
-
9.0
-
13.5
V
---
CL = 500pF, VSENSE = -VIN
VLOCK
Supply
Shutdown Logic
tSD
Shutdown delay
#
-
50
100
ns
tSW
Shutdown pulse width
#
50
-
-
ns
tRW
RESET pulse width
#
50
-
-
ns
---
tLW
Latching pulse width
#
25
-
-
ns
Shutdown and reset low
VIL
Input low voltage
-
-
-
2.0
V
---
VIH
Input high voltage
-
7.0
-
-
V
---
IIH
Input current, input high voltage
-
-
1.0
5.0
μA
VIN = VDD
IIL
Input current, input low voltage
-
-
-25
-35
μA
VIN = 0V
VOH
Output high voltage
-
VDD - 0.3
-
-
V
IOUT = 10mA,
VOL
Output low voltage
-
-
-
0.2
V
IOUT = -10mA
Pull up
-
-
15
25
Ω
Pull down
-
-
8.0
20
Ω
Pull up
-
-
20
30
Ω
Pull down
-
-
10
30
Ω
IOUT = ±10mA,
TA = -55°C to 125°C
Output
ROUT
Output resistance
IOUT = ±10mA
tR
Rise time
#
-
30
75
ns
CL = 500pF
tF
Fall time
#
-
20
75
ns
CL = 500pF
Notes:
# Guaranteed by design. Not subject to production test.
3
HV9112
Truth Table
Shutdown
Reset
Output
H
H
H
H→L
L
H
Off, not latched
L
L
Off, latched
L→H
L
Off, latched, no change
Normal operation
Normal operation, no change
Shutdown Timing Waveforms
1.5V
tF ≤ 10ns
VDD
tR ≤ 10ns
50%
Sense
50%
Shutdown
0
0
td
t SD
VDD
Output
VDD
90%
Output
0
0
t SW
VDD
50%
Shutdown
90%
tR, tF ≤ 10ns
50%
0
t LW
VDD
Reset
50%
50%
50%
0
t RW
Functional Block Diagram
FB
COMP
14
(19)
Discharge
13
(18)
9
(12)
OSC
IN
OSC
OUT
8 (11)
7 (10)
Error
Amplifier
OSC
–
10 (14)
VREF
+
2V
Modulator
Comparator
–
4V
4 (6)
Q
Output
S
+
Current
Sources
To
Internal
Circuits
5 (8)
Current Limit
Comparator
–
1 (20)
To VDD
Q
R
+
REF
GEN
BIAS
T
-VIN
1.2V
3 (5)
6 (9)
Current Sense
VDD
VDD
2 (3)
–
+VIN
11 (16)
Undervoltage
Comparator
Shutdown
S
Q
8.1V
–
+
Reset
R
+
12 (17)
8.6V
Pre-regulator/Startup
4
HV9112
Typical Performance Curves
Fig. 1
Fig. 4
Error Amplifier Output Impedance (Z0)
1M
6
10
Output Switching Frequency
vs. Oscillator Resistance
105
fOUT (Hz)
ZO (Ω)
104
103
102
100k
10
1
.1
1KHz
100KHz
10KHz
1MHz
10k
10k
10MHz
100 k
Frequency
PSRR — Error Amplifier and Reference
Fig. 2
Fig. 5
0
80
-10
70
-20
Gain (dB)
-30
PSSR (dB)
1M
ROSC (Ω)
-40
-50
-60
-70
Error Amplifier
Open Loop Gain/Phase
60
180
50
120
40
60
30
0
20
-60
10
-120
0
-180
-10
-80
10
100
1K
10K
100K
1M
100
1K
100K
10K
1M
Frequency (Hz)
Frequency (Hz)
RDISCHARGE vs. tOFF (9113 only)
100
Fig. 6
104
ROSC = 100K
VDD = 12V
VDD = 10V
tOFF (nsec)
Bias Current (µA)
Fig. 3
10
103
ROSC = 10K
ROSC = 1K
1
105
10
6
102
10-1
107
100
101
102
103
RDISCHARGE (Ω)
Bias Resistance (Ω)
5
104
105
106
Phase (°C)
100Hz
HV9112
Test Circuits
Error Amp ZOUT
+10V
(VDD)
0.1V swept 10Hz – 1MHz
PSRR
1.0V swept 100Hz – 2.2MHz
100K1%
60.4K
–
(FB)
+
Reference
GND
(–VIN)
100K1%
10.0V
V1
Tektronix
P6021
(1 turn
secondary)
4.00V
V2
+
Reference
40.2K
0.1µF
V1
–
V2
0.1µF
NOTE: Set Feedback Voltage so that
VCOMP = VDIVIDE ± 1mV before connecting transformer
Detailed Description
Preregulator
Bias Circuit
The preregulator/startup circuit for the HV9112 consists of
a high-voltage n-channel depletion-mode DMOS transistor driven by an error amplifier to form a variable current
path between the VIN terminal and the VDD terminal. The
maximum current (about 20 mA) occurs when VDD = 0, with
current reducing as VDD rises. This path shuts off altogether
when VDD rises to somewhere between 7.8 and 9.4V, so that
if VDD is held at 10 or 12V by an external source(generally the
supply the chip is controlling). No current other than leakage
is drawn through the high voltage transistor. This minimizes
dissipation.
An external bias resistor, connected between the BIAS pin
and VSS is required by the HV9112 to set currents in a series of current mirrors used by the analog sections of the
chip. The nominal external bias current requirement is 15 to
20µA, which can be set by a 390KΩ to 510KΩ resistor if a
10V VDD is used, or a 510kΩ to 680KΩ resistor if VDD will be
12V. A precision resistor is not required; ± 5% is fine.
Clock Oscillator
The clock oscillator of the HV9112 consists of a ring of CMOS
inverters, timing capacitors, a capacitor discharge FET, and,
in the 50% maximum duty cycle versions, a frequency dividing flip-flop. A single external resistor between the OSC IN
and OSC OUT is required to set the oscillator frequency (see
graph). For the 50% maximum duty cycle versions the Discharge pin is internally connected to GND. For the 99% duty
cycle version, the Discharge pin can either be connected to
VSS directly or connected to VSS through a resistor used
to set a deadtime. One major difference exists between the
Supertex HV9112 and competitive 9110’s. On the Supertex
part, the oscillator is shut off when a shutoff command is received. This saves about 150µA of quiescent current, which
aids in the construction of power supplies that meet CCITT
specification I-430, and in other situations where an absolute minimum of quiescent power dissipation is required.
An external capacitor between VDD and VSS is generally
required to store energy used by the chip in the time between shutoff of the high voltage path and the VDD supply’s
output rising enough to take over powering the chip. This
capacitor should have a value of 100X or more the effective
gate capacitance of the MOSFET being driven, i.e.,
CSTORAGE ≥ 100 x (gate charge of FET at 10V ÷ 10V)
as well as very good high frequency characteristics. Stacked
polyester or ceramic caps work well. Electrolytic capacitors
are generally not suitable.
A common resistor divider string is used to monitor VDD for
both the under voltage lockout circuit and the shutoff circuit
of the high voltage FET. Setting the under voltage sense
point about 0.6V lower on the string than the FET shutoff
point guarantees that the under voltage lockout always releases before the FET shuts off.
6
HV9112
Reference
Current Sense Comparators
The Reference of the HV9112 consists of a stable bandgap
reference followed by a buffer amplifier which scales the
voltage up to approximately 4.0V. The scaling resistors of
the reference buffer amplifier are trimmed during manufacture so that the output of the error amplifier, when connected
in a gain of –1 configuration, is as close to 4.0V as possible.
This nulls out any input offset of the error amplifier. As a consequence, even though the observed reference voltage of a
specific part may not be exactly 4.0V, the feedback voltage
required for proper regulation will be.
The HV9112 uses a true dual comparator system with independent comparators for modulation and current limiting.
This allows the designer greater latitude in compensation
design, as there are no clamps (except ESD protection) on
the compensation pin. Like the error amplifier, the comparators are of low-noise BiCMOS construction.
Remote Shutdown
The shutdown and reset pins of the 9110 can be used to
perform either latching or non-latching shutdown of a converter as required. These pins have internal current source
pull-ups so they can be driven from open drain logic. When
not used they should be left open, or connected to VDD.
A ≈ 50KΩ resistor is placed internally between the output of
the reference buffer amplifier and the circuitry it feeds (reference output pin and non-inverting input to the error amplifier). This allows overriding the internal reference with a low
impedance voltage source ≤6.0V. Using an external reference reinstates the input offset voltage of the error amplifier,
and its effect of the exact value of feedback voltage required.
Because the reference of the HV9112 is a high impedance
node, and usually there will be significant electrical noise
near it, a bypass capacitor between the reference pin and
VSS is strongly recommended. The reference buffer amplifier is intentionally compensated to be stable with a capacitive load of 0.01 to 0.1µF.
Output Buffer
The output buffer of the HV9112 is of standard CMOS construction (P-channel pull-up, N-channel pull-down). Thus the
body-drain diodes of the output stage can be used for spike
clipping if necessary, and external Schottky diode clamping
of the output is not required.
Error Amplifier
The error amplifier in the HV9112 is a true low-power differential input operational amplifier intended for around the
amplifier compensation. It is of mixed CMOS-bipolar construction: A PMOS input stage is used so the common mode
range includes ground and the input impedance is very high.
This is followed by bipolar gain stages which provide high
gain without the electrical noise of all-MOS amplifiers. The
amplifier is unity gain stable.
7
HV9112
14-Lead SOIC (Narrow Body) Package Outline (NG)
8.65x3.90mm body, 1.27mm pitch
D
14
θ1
E1
Note 1
(Index Area
D/2 x E1/2)
E
1
L
L2
Gauge
Plane
θ
Seating
Plane
L1
Top View
View B
A
View
B
h
A A2
e
A1
Note 1
h
Seating
Plane
b
A
Side View
View A-A
Note 1:
This chamfer feature is optional. If it is not present, then a Pin 1 identifier must be located in the index area indicated.The Pin 1 identifier may be either a
mold, or an embedded metal or marked feature.
Symbol
A
MIN
Dimension
(mm)
NOM
MAX
1.35
1.75
A1
0.10
0.25
A2
1.25
1.65
b
0.31
0.51
D
8.55
8.65
8.75
E
5.80
6.00
6.20
E1
e
3.80
3.90
4.00
h
0.25
1.27
BSC
0.50
L
L1
L2
0.40
1.27
θ
0
1.04
REF
0.25
BSC
O
O
8
θ1
5O
15O
JEDEC Registration MS-012, Variation AB, Issue E, Sept. 2005.
Drawinngs not to scale.
(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.)
Doc.# DSFP-HV9112
A101007
8