SP4501 Datasheet, PDF (9/13 Pages) Sipex Corporation – EL Plus Piezo Driver

PIN ASSIGNMENTS
Pin 1 — ELEN — Electroluminescent Lamp
Enable. When driven HIGH, this input pin
enables the EL driver outputs. This pin has
an internal pulldown resistor.
Pin 2 — PZEN — Piezo Enable. When this input
pin is driven HIGH, the piezo operates at a
frequency f_OSC/16. When this input pin is
LOW, the clock signals applied to PZCK or
PZCK will drive the internal piezo circuitry.
This pin has an internal pulldown resistor.
Pin 3 — R_OSC — Oscillator Resistor. Connecting
a resistor between this pin and V sets the
DD
frequency of the internal clock.
Pin 4 — PZCK — Inverse Piezo Clock. When
PZEN is LOW, the internal piezo circuit will
operate at the frequency of the clock signal
applied to this input pin. For the piezo driver
to rest in the inactive mode, it is required that
PZCK remains at logic HIGH. This pin has
an internal pullup resistor.
Pin 5 — PZCK — Piezo Clock. When PZEN is
LOW, the internal piezo circuit will operate
at the frequency of the clock signal applied to
this input pin. For the piezo driver to rest in
the inactive mode, it is required that PZCK
remains at logic LOW. This pin has an
internal pulldown resistor.
Pin 6 — No connect.
.
Pin 7 — V — Power Supply Ground. Connect
SS
to the lowest circuit potential, typically ground
Pin 8 — COIL — Coil. The inductor for the
boost converter is connected from V_BATT to
this pin.
Pin 9 — CAP — Integrator Capacitor. An
integrator capacitor connected from this pin
to ground filters out any coil switching spikes
or ripple present in the output waveform to
the EL lamp. Connecting a fast recovery
diode from COIL to CAP increases the light
output of the EL lamp.
Pin 10 — PZ1 — Piezotransducer Output. Con-
nect this pin to the piezotransducer.
Pin 11 — PZ2 — Piezotransducer Output. Con-
nect this pin to the piezotransducer.
Pin 12 — EL1 — Electroluminescent Lamp
Output. Connect this pin to the EL lamp.
Pin 13 — EL2 — Electroluminescent Lamp
Output. Connect this pin to the EL lamp.
Pin 14 — V_DD — Positive Power Supply. This
pin should be bypassed with a 0.1µF capaci-
tor.
11-14-00
SP4501 EL Plus Piezo Driver
9
© Copyright 2000 Sipex Corporation