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HV430
High Voltage Ring Generator
Features
105Vrms ring signal
Output over current protection
5.0V CMOS logic control
Logic enable/disable to save power
Adjustable deadband in single-control mode
Power-on reset
Fault output for problem detection
Applications
Line access cards
Set-top/Street box
General Description
The Supertex HV430 is a high voltage PWM ring generator
integrated circuit. The high voltage outputs, V
PGATE
and V
NGATE
,
are used to drive the gates of external high voltage P-channel
and N-channel MOSFETs in a push-pull configuration. Over
current protection is implemented for both the P-channel and N-
channel MOSFETs. External sense resistors set the over-cur-
rent trip point.
The RESET input functions as a power-on reset when connected
to an external capacitor.
The FAULT output indicates an over-current condition and is
cleared after 4 consecutive cycles with no overcurrent condition.
A logic low on RESET or ENABLE clears the FAULT output. It is
active-low and open-drain to allow wire OR’ing of multiple
drivers.
P
gate
and N
gate
are controlled independently by logic inputs P
IN
and
N
IN
when the MODE pin is at logic high. A logic high on P
IN
will turn
on the external P-channel MOSFET. Similarly, a logic high on N
IN
will turn on the external N-channel MOSFET. Lockout circuitry
prevents the N and P switches from turning on simultaneously.
A pulse width limiter restricts pulse widths to no less than 100-
200ns.
For applications where a single control input is desired, the
MODE pin should be connected to SGND. The PWM control
signal is then input to the N
IN
pin. A user-adjustable deadband in
the control logic ensures break-before-make on the outputs,
thus avoiding cross conduction on the high voltage output during
switching. A logic high on N
IN
will turn the external P-Channel
MOSFET on and the N-Channel off, and vice versa. The IC can
be powered down by applying a logic low on the ENABLE pin,
placing both external MOSFETs in the off state.
Absolute Maximum Ratings
V
PP1
– V
NN1
, power supply voltage
+340V
V
PP1
, positive high voltage supply
+220V
V
PP2
, positive gate voltage supply
+220V
V
NN1
, negative high voltage supply
-220V
V
NN2
, negative gate voltage supply
-220V
V
DD
, logic supply
+7.5V
Storage temperature
-65
°
C to +150
°
C
Power dissipation
600mW
Ordering Information
Operating Voltage
Package Options
V
PP1
-V
NN1
SOW-20
325V
HV430WG
09/21/00
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.