SUPERTEX HV9108

HV9105
HV9108
High-Voltage Switchmode Controllers with MOSFET
Ordering Information
MOSFET Switch
+VIN
Package Outlines
BVDSS
RDS(ON)
Min
Max
Feedback
Voltage
Max
Duty Cycle
14 Pin Plastic DIP
20 Pin Plastic PLCC
200V
5.0Ω
10V
120V
±1%
49%
HV9105P
HV9105PJ
200V
5.0Ω
10V
120V
±1%
99%
HV9108P
HV9108PJ
Standard temperature range for all parts is industrial (-40° to +85°C).
Features
General Description
❏
10 to 120V input range
❏
200V, 5Ω output MOSFET
❏
Current-Mode Control
❏
High Efficiency
The Supertex HV9105 and HV9108 are high-efficiency high
voltage SMPS ICs intended for use in power converters requiring
extreme efficiency at output power levels of 5.0W or less. The low
supply current (0.5mA max) allows them to be used to build
supplies which meet CCITT I.430 performance recommendations (60% efficiency at .025W out).
❏
CCITT Compatible
❏
Internal Start-up Circuit
The HV9105/08 provides all the functions necessary to build a
single-switch current-mode converter of any common topology,
with a minimum of external parts.
In addition to high efficiency, because it uses Supertex’s proprietary high voltage BiCMOS/DMOS technology, the HV9105/08
offers numerous performance advantages when compared to
conventional PWM ICs. Dynamic range is approximately 8 times
wider than with bipolar ICs, both response speed and maximum
clock rate are faster, and no external power resistors or zeners are
necessary for high voltage starting.
Applications
❏ DC/DC Converters
❏ Distributed Power Systems
❏ ISDN Equipment
Accessory circuits are included to provide either latching or
nonlatching shutdown. When shut down, device dissipation is
less than 4mW.
❏ PBX Systems
❏ Modems
The HV9105/08 is intended for operation with input voltages from
10 to 120VDC.
Absolute Maximum Ratings
+VIN, Input Voltage
120V
VDS
200V
VDD, Logic Voltage
15.0V
Control Inputs
ID (Peak)
Storage Temperature
Power Dissipation, Plastic DIP
Power Dissipation, PLCC
-0.3V to VDD+0.3V
2.5A
-65°C to 150°C
750mW
1400mW
For detailed circuit and application information, please refer
to application notes AN-H13 and AN-H21 to AN-H24.
11/12/01
Supertex Inc. does not recommend the use of its products in life support applications and will not knowingly sell its products for use in such applications unless it receives an adequate "products liability
indemnification insurance agreement." Supertex does not assume responsibility for use of devices described and limits its liability to the replacement of devices determined to be defective due to
workmanship. No responsibility is assumed for possible omissions or inaccuracies. Circuitry and specifications are subject to change without notice. For the latest product specifications, refer to the
Supertex website: http://www.supertex.com. For complete liability information on all Supertex products, refer to the most current databook or to the Legal/Disclaimer page on the Supertex website.
1
HV9105/HV9108
Electrical Characteristics
(VDD = 10V, +VIN = 48V, Discharge = -VIN = 0V, RBIAS = 820KΩ, ROSC = 910KΩ,TA = 25°C, unless otherwise specified)
Symbol Parameters
Min
Typ
Max
Unit
Conditions
3.92
4.00
4.08
V
RL = 10MΩ
15
30
45
KΩ
130
µA
Reference
VREF
Output Voltage
Impedance1
ZOUT
Output
ISHORT
Short Circuit Current
100
∆VREF
Change in VREF with Temperature
0.25
mV/°C
MHz
VREF = -VIN
Oscillator
fMAX
Maximum Oscillator Frequency
1.0
3.0
fOSC
Initial Accuracy2
32
40
Voltage Stability1
Temperature Coefficient1
48
KHz
15
%
170
ROSC = 0Ω
9.5V < VDD < 13.5V
ppm/°C
PWM
DMAX
Maximum Duty Cycle1
Deadtime1
DMIN
HV9105
49.0
49.4
49.6
HV9108
99.0
99.4
99.6
HV9108
100
Minimum Duty Cycle
Minimum Pulse Width
Before Pulse Drops Out1
%
nsec
0
%
110
175
nsec
4.00
4.04
V
VFB Shorted to Comp
25
500
nA
VFB = 4.0V
Error Amplifier
VFB
Feedback Voltage
IIN
Input Bias Current
VOS
Input Offset Voltage
AVOL
gbw
Open Loop Voltage
Unity Gain
3.96
Gain1
Bandwidth1
mV
60
80
dB
0.5
0.8
MHz
See Fig. 2
Ω
Impedance1
ZOUT
Output
ISOURCE
Output Source Current
ISINK
Output Sink Current
PSRR
nulled at trim
Power Supply
-1.3
50
-1.0
80
Rejection1
mA
VFB = 3.4V
µA
VFB = 4.5V
See Fig. 1
Current Limit
VSOURCE Threshold Voltage
td
1.0
1.2
1.4
V
VFB = 0V, RL = 100Ω
150
200
ns
VSOURCE = 1.5V, RL = 100Ω
Allowable Input Voltage
120
V
IIN = 10µA
Input Leakage Current
10
µA
VDD > 9.4V
Delay to Output1
Pre-Regulator/Startup
+VIN
VTH
VDD Pre-regulator Turn-off
Threshold Voltage
7.8
8.6
9.4
V
IPREREG = 10µA
VLOCK
Undervoltage Lockout
7.0
8.1
8.9
V
RL = 100Ω from Drain to VDD
Notes:
1. Guaranteed by design. Not subject to production test.
2. Stray capacitance on OSC IN pin ≤5pF.
2
HV9105/HV9108
Electrical Characteristics (Continued)
(VDD = 10V, +VIN = 48V, Discharge = -VIN = 0V, RBIAS = 820KΩ, ROSC = 910KΩ,TA = 25°C, unless otherwise specified)
Symbol Parameters
Min
Typ
Max
Unit
0.6
mA
Conditions
Supply
IDD
Supply Current
IBIAS
Bias Current
VDD
Operating Range
0.35
mA
7.5
µA
9.0
13.5
Shutdown = -VIN
V
Logic
tSD
Shutdown Delay Time1
tSW
Shutdown Pulse Width1
50
ns
tRW
RESET Pulse Width1
50
ns
tLW
Latching Pulse Width1
25
VIL
Input Low Voltage
VIH
Input High Voltage
IIH
Input High Current
1.0
5.0
µA
VIN = 10V
IIL
Input Low Current
-25
-35
µA
VIN = 0V
V
VSOURCE = Shutdown = 0V,
50
100
ns
VSOURCE = -VIN
ns
2.0
7.0
V
V
MOSFET Switch
BVDSS
Breakdown Voltage
200
240
ID = 100µA
RDS(ON)
Drain-to-Source On-resistance
3.5
IDSS
OFF State Drain Leakage Current
CDS
Drain Capacitance
35
Note:
1. Guaranteed by design. Not subject to production test.
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
3
5.0
Ω
VSOURCE = 0V, ID = 100mA
10
µA
VSOURCE = Shutdown = 0V,
VDRAIN = 100V
pF
VDS = 25V, Shutdown = 0V
HV9105/HV9108
Switching Waveforms
1.5V
tF ≤ 10ns
VDD
tR ≤ 10ns
50%
Source
50%
SHUTDOWN
0
0
td
t SD
VDD
Drain
VDD
90%
Drain
0
90%
0
t SW
VDD
Shutdown
50%
tR, tF ≤ 10ns
50%
0
t LW
VDD
Reset
50%
50%
50%
0
t RW
Functional Block Diagram
FB
14
(20)
COMP
13
(18)
Error
Amplifier
OSC OSC
In Out
Discharge
8
(11)
9
(12)
OSC
–
10 (14)
+
VREF
2V
Current-mode
Comparator
–
4V
VDD
R
Q
S
To
Internal
Circuits
Current
Sources
Q
9105
9108
V DD
+
Drain
(5) 3
C/L
Comparator
–
1 (2)
T
+
REF
GEN
BIAS
7
(10)
(8) 5
1.2V
-V IN
V DD
6 (9)
2 (3)
–
+VIN
Undervoltage
Comparator
S
Source
(7) 4
(16) 11
Shutdown
Q
8.1V
–
+
Reset
R
+
(17) 12
8.6V
Pre-regulator/Startup
Pin numbers in parentheses are for PLCC package.
4
HV9105/HV9108
Typical Performance Curves
80
0
70
240°
60
180°
50
120°
40
60°
30
0°
20
-60°
-60
10
-120°
-70
0
-180°
-10
-20
Gain (dB)
-30
(dB)
Error Amplifier
Open Loop Gain/Phase
Fig. 3
PSRR – Error Amplifier and Reference
-40
-50
-10
-80
10Hz
100Hz
1KHz
10KHz
100KHz
100Hz
1MHz
1KHz
10KHz
100KHz
1MHz
Frequency
Fig. 2
Error Amplifier Output Impedance (Z0)
Output Switching Frequency
vs. Oscillator Resistance
Fig. 4
1M
106
105
104
fOUT (Hz)
(Ω)
HV9108
HV9105
103
102
100k
10
1.0
0.1
10k
10k
.01
100Hz
1KHz
10KHz
1MHz
100KHz
10MHz
100 k
1M
ROSC (Ω)
Test Circuits
Error Amp ZOUT
PSRR
0.1V swept 10Hz – 1MHz
+10V
(VDD)
1.0V swept 100Hz – 2.2MHz
100K1%
60.4K
–
(FB)
GND
(–VIN)
10.0V
+
Reference
100K1%
V1
Tektronix
P6021
(1 turn
secondary)
4.00V
V2
Reference
40.2K
0.1µF
0.1µF
NOTE: Set Feedback Voltage so that
VCOMP = VDIVIDE ± 1mV before connecting transformer
5
V1
–
+
V2
Phase
Fig. 1
HV9105/HV9108
Technical Description
Preregulator
Reference
The preregulator/startup circuit for the HV9105/08 consists of a
high-voltage N-channel depletion-mode DMOS transistor driven
by an error amplifier to form a controlled current path between the
VIN terminal and the VDD terminal of the HV9105/08. 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.
The reference section of the HV9105/08 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 4.000V 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 4.0V.
An external capacitor between VDD and VSS is generally required
to store energy used by the chip during the time between shutoff
of the high voltage path and the VDD supply’s output rising enough
to take over the powering of the chip. This capacitor generally also
serves as the output filter capacitor for that output from the supply.
1.0µF is generally sufficient to assure against double-starting.
Capacitors as small as 0.1µF can work when faster response from
the VDD line is required. The chosen capacitor should have very
good high frequency characteristics and be mounted so that the
sum of the lead length between capacitor and IC for both leads is
less than 2.5 cm. Stacked polyester or ceramic capacitors work
well. Electrolytic capacitors are generally not suitable.
A resistor of approximately 50KΩ 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 lowimpedance voltage source ≤6.0V. In general, because the reference voltage of the Supertex HV9105/08 is not noisy, as some
previous devices have been, overriding the reference should
seldom be necessary.
Because the reference 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.
A common resistor divider string is used to monitor VDD for both
the undervoltage lockout circuit and the shutoff circuit of the high
voltage FET. Setting the undervoltage sense point about 0.6V
lower on the string than the FET shutoff point guarantees that the
undervoltage lockout always releases before the FET shuts off.
Error Amplifier
The error amplifier 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.
Bias Circuit
An external bias resistor, connected between the bias pin and VSS
is required by the HV9105/08 to set currents in a series of current
mirrors used by the analog sections of the chip. Nominal external
bias current requirement is 7.5µA, which can be set by a 820KΩ
to 1.3MΩ resistor if a 10V VDD is used, or a 1.2MΩ to 2.0MΩ
resistor if a 12V VDD is used. A precision resistor is NOT required;
± 5% is fine.
Current Sense Comparators
The HV9105/08 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.
For extremely low power operation, the value of bias current can
be reduced to as low as 4.0µA by further increases in the value of
the bias resistor.
Clock Oscillator
Remote Shutdown
The clock oscillator of the HV9105/08 consists of a ring of CMOS
inverters, timing capacitors, a capacitor discharge FET, and, in
the 50% maximum duty cycle version, a frequency dividing flipflop. A single external resistor between the OSC In and OSC Out
pins is required to set oscillator frequency (see Fig. 4). For the
50% maximum duty cycle versions the ‘Discharge’ pin is internally
connected to GND. For the 99% duty cycle version, ‘Discharge’
can either be connected to VSS directly or connected to VSS
through a resistor used to set a deadtime.
The shutdown and reset pins 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.
Main Switch
The main switch is a normal N-channel power MOSFET. Unlike
the situation with competitive devices, the body diode can be used
if desired without destroying the chip.
One difference exists between the Supertex HV9105/08 and
competitive 9105 parts. The oscillator of the Supertex HV9105/08
is shut off when a shutoff command is received. This saves about
100µA of quiescent current, which aids in the construction of
power supplies to meet CCITT specification I.430, and in other
situations where an absolute minimum of quiescent power dissipation is required.
6
HV9105/HV9108
+VIN
2
13
COMP
Drain
3
12
Reset
Source
4
11
Shutdown
–VIN
5
10
VREF
VDD
6
9
Discharge
OSC Out
7
8
OSC In
Reset
Shutdown
NC
VREF
15
14
NC
19
13
NC
Feedback
20
12
Discharge
NC
1
11
OSC In
BIAS
2
10
OSC Out
+VIN
3
9
VDD
14 Pin DIP Package
•
NC
4
5
6
7
8
–VIN
Feedback
16
Source
14
17
NC
1
18
Drain
BIAS
COMP
Pinout
20-pin PJ Package
top view
11/12/01
©2001 Supertex Inc. All rights reserved. Unauthorized use or reproduction prohibited.
7
1235 Bordeaux Drive, Sunnyvale, CA 94089
TEL: (408) 744-0100 • FAX: (408) 222-4895
www.supertex.com