Microchip HV857L Bedienungsanleitung


Lies die bedienungsanleitung für Microchip HV857L (8 Seiten) kostenlos online; sie gehört zur Kategorie Nicht kategorisiert. Dieses Handbuch wurde von 24 Personen als hilfreich bewertet und erhielt im Schnitt 4.9 Sterne aus 12.5 Bewertungen. Hast du eine Frage zu Microchip HV857L oder möchtest du andere Nutzer dieses Produkts befragen? Stelle eine Frage

Seite 1/8
Supertex inc.
Supertex inc.
www.supertex.com
Doc.# DSFP-HV857L
A062013
HV857L
Features
Audible noise reduction
190 V
PP
output voltage for higher brightness
Single cell lithium ion compatible
150nA shutdown current
Wide input voltage range 1.8V to 5.0V
Separately adjustable lamp and converter
frequencies
Output voltage regulation
Split supply capability
Available in 8-Lead DFN and 8-Lead MSOP-
packages
Applications
Mobile cellular phones
Keypad backlighting
LCD backlighting
PDAs
Handheld wireless communication products
Global Positioning Systems (GPS)
General Description
The Supertex HV857L is a low noise, high voltage driver designed
for driving Electroluminescent (EL) lamps of up to ve square
inches. It is the low noise version of the EL lamp driver HV857. The
input supply voltage range is from 1.8V to 5.0V. The device uses
a single inductor and a minimum number of passive components.
The nominal regulated output voltage that is applied to the EL
lamp is ±95V. The chip can be enabled/disabled by connecting the
resistor on RSW-Osc to VDD/ground.
The HV857L has two internal oscillators, a switching MOSFET,
and a high voltage EL lamp driver. The frequency for the switching
MOSFET is set by an external resistor connected between the RSW-
Osc pin and the supply pin, VDD. The EL lamp driver frequency
is set by an external resistor connected between the REL-Osc
and VDD pins. An external inductor is connected between the LX
and VDD pins, or VIN for split supply applications. A 0.003-0.1µF
capacitor is connected between CS and ground. The EL lamp is
connected between the VA and VB pins.
The switching MOSFET charges the external inductor and
discharges it into the capacitor at CS. The voltage at CS will start
to increase. Once the voltage at CS reaches a nominal value of
95V, the switching MOSFET is turned OFF to conserve power.
The outputs VA and VB are congured as an H bridge, and are
switching in opposite states to achieve ±95V across the EL lamp.
Typical Application Circuit
Low Noise, High Voltage
EL Lamp Driver IC
+
_
V
DD
C
DD
EL Lamp
+
_
C
S
V
IN
L
X
C
IN
Enable Signal
ON = V
DD
OFF = 0
D
R
SW
R
EL
1
2
3
4
8
7
6
5
HV857L
VDD
RSW-Osc
REL-Osc
GND
VA
VB
CS
LX


Produktspezifikationen

Marke: Microchip
Kategorie: Nicht kategorisiert
Modell: HV857L

Brauchst du Hilfe?

Wenn Sie Hilfe mit Microchip HV857L benötigen, stellen Sie unten eine Frage und andere Benutzer werden Ihnen antworten