HV57908
8MHz, 64-Channel Serial to Parallel Converter
with Push-Pull Outputs
Features
►
►
►
►
►
►
►
►
►
HVCMOS
®
technology
5V CMS Logic
Output voltage up to +80V
Low power level shifting
8MHz data rate
Latched data outputs
Forward and reverse shifting options (DIR pin)
Diode to V
PP
allows efficient power recovery
Outputs may be hot switched
General Description
The HV57908 is a low voltage serial to high voltage
parallel converter with push-pull outputs. The device has
been designed for use as a driver for EL displays. It can
also be used in any application requiring multiple output
high voltage current sourcing and sinking capability such
as driving plasma panels, vacuum fluorescent displays, or
large matrix LCD displays.
The device consists of a 64-bit shift register, 64 latches and
control logic to perform the polarity select and blanking of
the outputs. HVOUT1 is connected to the first stage of the
first shift register through the polarity and blanking logic.
Data is shifted through the shift registers on the logic low
to high transition of the clock. The DIR pin causes CCW
shifting when connected to GND, and CW shifting when
connected to VDD. A data output buffer is provided for
cascading devices. This output reflects the current status
of the last bit of the shift register (HVOUT64). Operation
of the shift register is not affected by the LE (latch enable),
BL (blanking), or the POL (polarity) inputs. Transfer of data
from the shift registers to the latches occurs when the LE
input is high. The data in the latches is stored when the LE
is low.
Functional Block Diagram
POL
BL
LE
VPP
DIOA
HVOUT1
Clock
HVOUT2
•
•
•
60 Additional
Outputs
•
•
•
HVOUT63
DIR
64-bit
Static Shift
Register
64 Latches
HVOUT64
DIOB
SUPERTEX [ Supertex, Inc ]
