HV441
High Voltage Ring Generator IC
Features
General Description
► 220V maximum operating voltage
► Integrated high voltage transistors
► Up to 70 VRMS ring signal
► Adjustable AC and DC output voltage level
► Adjustable ring signal start phase angle
► Pulse by pulse output over current protection
► 5 REN output capability
► External MOSFETs enhance output rating to 20 REN
Applications
► Stand alone high voltage ring generator
► Set-top/street box ring generator
► Pair gain ring generator
► Wireless local loops
► Fibre in the loop/to the curb
► Coax cable loop
The Supertex HV441 is a monolithic integrated circuit capable
of generating up to a 70VRMS sine wave output at frequencies
of 15 to 60Hz with a load of 5 North American RENs. Its output
rating can be enhanced to 20 North American RENs with the
addition of two Supertex MOSFETs: one N-Channel MOSFET,
the TN2524N8, and one P-Channel MOSFET, the TP2522N8.
The high voltage outputs have pulse by pulse over-current
protection set by two external sense resistors.
The HV441 generates a low voltage reference sine wave by
using external passive components. An external sine wave
signal can be used if desired. The HV441 amplifies the
reference sine wave signal by pulse width modulating the high
voltage output at a nominal frequency of 100KHz. An error
amplifier compares the output sine wave with the reference
sine wave and adjusts the pulse width accordingly. Both the
amplitude of the output sinewave and the DC offset voltage
are adjustable.
For detailed circuit and application information, please
refer to application note AN-H35.
Functional Block Diagram
Input2- Output2 VDD2
Input2+
Output1
Input1-
Input1+
VREF
ON/OFF
VDD1
OSC1
OSC2
OSC(IN)
OSC(OUT)
GND
-
+
op-amp2
VDD2
-
+
+
–
op-amp1 comp
OSC
÷4
VDD1
VDD2
Pulse Width
Regulator
Zero Voltage
Crossing
Detection
VDD2
Ramp
Generator
op-amp3 VDD2
+
–
High
Voltage
Level
Translator
Linear
Reg
Current
Sense
and
Driver
VDD2
High
Voltage
Level
Translator
Linear
Reg
Current
Sense
and
Driver
VPP1
VPSEN
VPGATE
VPP2
HVOUT
PGND
VNN2
VNGATE
VNSEN
VNN1
Input3+ Input3-
Output3
● 1235 Bordeaux Drive, Sunnyvale, CA 94089 ● Tel: 408-222-8888 ● www.supertex.com