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SP7619/19A
TM
Evaluation Board Manual
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Very low dropout voltage: 100mV
Accurate current regulation down to
dropout voltage
No external components
Output current 2 levels selectable
Power-saving shutdown mode of
12nA typical
PWM brightness control
Fast turn-on (<50µS)
Time Out function to protect the LED
Thermal Shutdown Protection
Space saving 2mm x 3mm 8 pin DFN
package
The
SP7619 Evaluation Board
is designed to help the user evaluate the performance of the SP7619 for
use as a single LED Driver. The evaluation board is a completely assembled and tested surface mount
board which provides easy probe access points to all SP7619 inputs and outputs so that the user can
quickly connect and measure electrical characteristics and waveforms. The Evaluation Board schematic
diagram is shown at Figure 1.
DESCRIPTION AND BOARD SCHEMATIC
Figure 1.The SP7619 Evaluation Board Schematic Diagram
*Note: While high current time duration is limited by the SP7619 in the range from 2 to 7s, we don’t
recommend pushing the button for a long time to prevent LED damage and battery discharge. LEDs
provide very bright light at 0.5/0.7A output current. Protect your eyes.
Dec 7-06
SP7619 Evaluation Board Manual
Page 1 of 4
© 2006 Sipex Corporation
INTRODUCTION
The SP7619 is a linear low side constant current driver designed to source two preset currents of
200mA/500mA (SP7619), 200mA/700mA (SP7619A)
*
. The preset currents can be set by selecting THE
CTRL pin to high or low. Dimming or shutdown can be done by feeding a PWM signal to the EN pin. Fast
EN turn-on/off time allows for very fast PWM dimming frequencies, completely eliminating flicker. The
driver acts as a current source ensuring constant LED current for a range of input voltage. The SP7619
allows for customer implementation of the lowest cost LED driver for a variety of applications. Internal
circuitry maintains the preset constant current output for a wide voltage range at the LED input. The built-
in thermal protection automatically stops LED current to prevent overheating. A timeout function serves
as a fail safe, shutting down the output for currents greater than 266mA after 4 seconds of continuous
operation if the enable input is not cycled.
Capacitor C1 is a decoupling capacitor. Resistor R1 is used to hold the device in a Sleep Mode at power
on if the ENABLE pin isn’t connected to Vin voltage. The SP7619 devices don’t have internal pull-
up/down resistors at the EN input and should be connected either to Vin or Ground. If the EN pin isn’t
used for modulation, it may be connected to Vin voltage directly using switch S1. Push button S2 is used
to set LED current. Low output current is set by default using resistor R2. To set high output current
value, connect the CTRL pin to Vcc (push button).
USING THE EVALUATION BOARD
1) Powering Up the SP7619 Circuit
The SP7619 Evaluation Board can be powered from a 4.5V power supply or from 3 alkaline cells.
Connect the 4.5V source pin with a short lead directly to the “Vin” and -4.5V /GND pin to the “GND”
posts. Connect the ENABLE pin to Vin voltage using shunt S1 (ON position).
2) Selecting the output current
The LED current may be set at 500 (700) mA by connecting the CTRL pin to the Vin voltage (push button
S2) or at 200 mA by connecting it to the ground (by default) respectively.*
The device provides high output current for 4 seconds only after setting the CTRL pin HIGH to protect
the LED. After that the device will go into shutdown mode.
Set the ENABLE pin LOW (switch S1 in position OFF) and then after that set it HIGH (S1 position ON) to
start the device again.
3) Dimming
The SP7619 can be pulse width modulated using the EN pin. Set switch S1 in the OFF position. Connect
the EN pin to the pulse generator with desired modulation frequency (positive pulse with amplitude from
2.4 to Vin voltage range). Changing the pulse duty cycle changes the average LED current.
Recommended modulation frequencies are from 100Hz to 2kHz with 10 – 90% duty cycle.
*
Contact Factory for additional current options
.
Dec 7-06
SP7619 Evaluation Board Manual
Page 2 of 4
© 2006 Sipex Corporation
ORDERING INFORMATION
Model
Temperature Range
Package Type
SP7619EB............................................. -40°C to +85°C..................................... SP7619 Evaluation Board
SP7619ER-L ....................................... -40° to +85° .....................Lead Free 8 Pin DFN (2mm x 3mm)
C
C
SP7619ER-L/TR ................................ -40° to +85° C .....................Lead Free 8 Pin DFN (2mm x 3mm)
C
SP7619AER-L...................................... -40° to +85° C .....................Lead Free 8 Pin DFN (2mm x 3mm)
C
SP7619AER-L/TR ............................... -40° to +85° C .....................Lead Free 8 Pin DFN (2mm x 3mm)
C
/TR = Tape and Reel
Pack quantity is 3,000 for DFN.
For further assistance:
Email:
WWW Support page:
Live Technical Chat:
Sipex Application Notes:
Sipexsupport@sipex.com
http://www.sipex.com/content.aspx?p=support
http://www.geolink-group.com/sipex/
http://www.sipex.com/applicationNotes.aspx
Solved by
TM
Sipex Corporation
Headquarters and
Sales Office
233 South Hillview Drive
Milpitas, CA95035
tel: (408) 934-7500
fax: (408) 935-7600
Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume
any liability arising out of the application or use of any product or circuit described herein; neither does it convey
any license under its patent rights nor the rights of others.
Dec 7-06
SP7619 Evaluation Board Manual
Page 4 of 4
© 2006 Sipex Corporation
Analog electronics
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