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Details, datasheet, quote on part number:ZXSC310E5
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Datasheet text preview:
ZXSC310
LED DRIVER SOLUTION FOR LCD BACKLIGHTING
DEVICE DESCRIPTION The ZXSC310 is a single or multi cell LED driver designed for LCD backlighting applications. The input voltage range of the device is between 0.8V and 8V. This means the ZXSC310 is compatible with single NiMH, NiCd or Alkaline cells, as well as multi-cell or LiIon batteries. The device features a shutdown control, resulting in a standby current less than 5µA, and an output capable of driving serial or parallel LED's. The circuit generates constant power output, which are ideal for driving single or multiple LED's over a wide range of operating voltages. These features make the device ideal for driving LED's particularly in LCD backlight applications for Digital Still cameras and PDA's. The ZXSC310 is a PFM DC-DC controller IC that drives an external Zetex switching transistor with a very low saturation resistance. These transistors are the best switching devices available for this type of conversion enabling high efficiency conversion with low input voltages. The drive output of the ZXSC310 LED driver generates a dynamic drive signal for the switching transistor. The circuit can start up under full load and operates down to an input voltage of 0.8 volts. The solution configuration ensures optimum efficiency over a wider range of load currents; several circuit configurations are possible depending on battery life versus brightness considerations. The ZXSC310 is offered in the SOT23-5 package which, when combined with a SOT23 switching transistor, generates a high efficiency small size circuit solution. The IC and discrete combination offers the ultimate cost Vs performance solution for LED backlight applications.
FEATURES
· 94% efficiency · Minimum operating input voltage 0.8V · Maximum operating input voltage 8V · Standby current less than 5µA · Programmable output current · Series or parallel LED configuration · Low saturation voltage switching transistor · SOT23-5 package
TYPICAL APPLICATIONS CIRCUIT
APPLICATIONS
· LCD backlights:
Digital still camera PDA Mobile phone
· LED flashlights and torches · White LED driving · Multiple LED driving
V IN = 3 . 3 V / 5 V
V
CC
V D R IV E S TDN I SENSE
G ND
ORDERING INFORMATION
DEVICE REEL SIZE ZXSC310E5 180mm TAPE WIDTH 8mm QUANTITY PER REEL 3000
DEVICE MARKINGS
· C310
ISSUE 1 - SEPTEMBER 2002 1
ZXSC310
ABSOLUTE MAXIMUM RATINGS:
Supply Voltage Maximum Voltage other pins Power Dissipation Operating Temperature Storage Temperature ELECTRICAL CHARACTERISTICS: -0.3 to 10V -0.3 to VCC+0.3V 450mW -40 to 85 °C -55 to 125°C
Test conditions unless otherwise stated: VCC=1.5V, TAMB=25 C
Symbol Parameter Efficiency 1 VCC VCC(min) Recommended supply voltage range Minimum startup and operating voltage Quiescent current2 Base drive current Supply current3 IDRIVE=-600µA, VDRIVE=0.7V IDRIVE=-600µA, VDRIVE=0.7V, TAMB=-10°C3 VEN = VCC (enabled) VEN = 0V (standby) IVDRIVE ICC VVDRIVE(high) VVDRIVE(low) VSTDN(high) VSTDN(low) ISTDN VISENSE
(threshold)
Conditions
Min
Typ
Max 94
Units % V V
0.8 0.8 0.9 0.2 4 1.5 2
8 0.92
IQ
mA 5 3.5 4 µA mA mA
VDRIVE = 0.7V, VISENSE = 0V VDRIVE = 0.7V, VISENSE = 0V VISENSE = 0V, IVDRIVE =-0.5mA VISENSE = 50mV, IVDRIVE = 5mA
High level drive voltage Low level drive voltage Device enabled Device in standby mode Enable input current Output current reference voltage ISENSE voltage temp co.2 ISENSE input current
VCC -0.3 0 0.7
VCC 0.2
V V V
0.15 -1 14 19 0.4 VISENSE = 0V 0 -30 -65 1 24
V µA mV %/°C µA
TCVISENSE IISENSE
ELECTRICAL CHARACTERISTICS: AC PARAMETERS2 Test conditions unless otherwise stated: VCC=1.5V, TAMB=0 to 70 C
Symbol TDRV FOSC Parameter Discharge Pulse Width Recommended operating frequency4 Conditions Min 1.2 Typ 1.7 Max 3.2 200 Units µs kHz
1 Application dependent, see reference designs 2 These parameters guaranteed by Design 3 Total supply current =IQ + IVDRIVE, see typical characteristics 4 Operating frequency is application circuit dependent. See applications section.
ISSUE 1 - SEPTEMBER 2002 2
ZXSC310
FMMT618
For the circuits described in the applications section Zetex FMMT618 is the recommended pass transistor. The following indicates outline data for the device, more detailed information can be found in the Zetex surface mount products data book or on Zetex Web page: www.zetex.com
ELECTRICAL CHARACTERISTICS: Test conditions unless otherwise stated: TAMB=25 C
Symbol VCE(sat) Parameter Collector-Emitter Saturation Voltage5 Conditions IC=0.1A, IB=10mA IC=1A, IB=10mA IC=2.5A, IB=50mA V(BR)CEO
5
Min
Typ 8 70 130
Max 15 150 200
Units mV
Collector-Emitter Breakdown Voltage5
IC=10mA
20
27
V
Measured under pulse conditions. Pulse width=300µs. Duty cycle
2%
ZHCS1000
For the maximum brightness circuit described in the applications section Zetex ZHCS1000 is the recommended Schottky diode. The following indicates outline data for the ZHCS, more detailed information can be found on Zetex Web page: www.zetex.com
ELECTRICAL CHARACTERISTICS: Test conditions unless otherwise stated: TAMB=25 C
Symbol VF trr Parameter Forward voltage Reverse Recovery Time Conditions IF = 500mA IF = 1A Switched from IF=500mA to IR=500mA. Measured at IR=50mA IR Reverse Current VR = 30V 50 100 µA 12 Min Typ Max 400 500 ns Units mV
Part Number
VR Max. V
IF Max. mA 200 2000 1000 750 500 400
IFSM Max. A 0.6 20 12 12 6.75 6.75
VF at Max. mV 500 500 500 540 550 500 IF mA 30 2000 1000 750 500 400
IR at Max. A 250 1000 100 100 40 40 VR V 25 30 30 30 30 30
Capacitance at VR = 25V, f = 1MHz Typ. pF 10 60 25 25 20 20
Package SOT23 SOT23-6 SOT23 SOT23 SOT23 SOT23 SOT323
BAT54 ZHCS2000 ZHCS1000 ZHCS750 ZHCS500 ZHCS400
30 40 40 40 40 40
ISSUE 1 - SEPTEMBER 2002 3
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