ZLED7000 [IDT]
40V LED Driver with Internal Switch;
| 型号： | ZLED7000 |
| 厂家： | 
INTEGRATED DEVICE TECHNOLOGY |
| 描述： | 40V LED Driver with Internal Switch |
| 文件： | 总18页 (文件大小：564K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
ZLED7000
40V LED Driver with Internal Switch
Datasheet
Brief Description
Features
The ZLED7000, one of our ZLED Family of LED control
ICs, is an inductive step-down converter that is optimal
for driving a single LED or multiple LEDs (connected in
series) from a voltage source greater than the voltage
rating of the LED. The ZLED7000 operates in continu-
ous mode. Capable of operating efficiently with voltage
supplies ranging from 6 VDC to 40 VDC, it is ideal for
low-voltage lighting applications. The ZLED7000
minimizes current consumption by remaining in a low-
current standby mode (output is off) until a voltage of
≥0.3V is applied to the ADJ pin.
• Capable of up to 95% efficiency*
• Operates in continuous mode with a wide input
range from 6 VDC to 40 VDC
• Integrated 40V power switch
• One pin on/off or brightness control via PWM or DC
voltage control signal input
• Switching frequency: ≤ 1MHz
• Dimming rate: 1200:1 (typical)
• Output current accuracy: 5% (typical)
• Built-in thermal shutdown and open-circuit protection
In operating mode, the ZLED7000 can source LEDs with
an output current of ≤ 750mA (≤ 30 watts of output
power) that is externally adjustable.* The ZLED7000’s
integrated output switch and high-side current sensing
circuit use an external resistor to adjust the average
output current. Linearity is achieved via an external
control signal at the ZLED7000’s ADJ pin, implemented
either as a pulse-width modulation (PWM) waveform for
a gated output current or a DC voltage for a continuous
current.
for LED
• Very few external components needed for operation
• Broad range of applications: outputs up to ≤750mA
• SOT89-5 package
Application Examples
• Illuminated LED signs and other displays
• LED traffic and street lighting (low-voltage)
• Architectural LED lighting, including low-voltage
applications for buildings
• Halogen replacement LEDs (low-voltage)
• LED backlighting
• General purpose exterior and interior LED lighting,
including applications requiring low-voltage
• General purpose low-voltage industrial applications
ZLED7000 Application Circuit
6 to 40 VDC
RS
VS
D1
5
4
n LED
C1
1μF
VIN
ISENSE
ZLED7000
L1
3
1
LX
ADJ
GND
47μH
2
* See section 2.3 and 1.4 for details
© 2016 Integrated Device Technology, Inc.
1
April 20, 2016
ZLED7000
40V LED Driver with Internal Switch
Datasheet
SOT89-5 Package Dimensions and Pin Assignments
D
A
D1
1
2
5
4
LX
VIN
E1
E
GND
ADJ
Thermal Pad
ISENSE
b1
3
L
e
b
c
e1
Dimension (mm)
Dimension (mm)
Symbol
Symbol
Min
Max
Min
Max
2.600
4.250
A
b
1.400
0.320
0.360
0.350
4.400
1.400
1.600
0.520
0.560
0.440
4.600
1.800
E
E1
e
2.300
3.940
b1
c
1.500 Typ
e1
L
2.900
0.900
3.100
1.100
D
D1
Ordering Information
Product Sales Code
ZLED7000ZI1R
Description
ZLED7000 – 40V LED Driver
Package
SOT89-5 (Tape & Reel)
Kit
ZLED7000KIT-D1
ZLED7000 used in a MR16 Halogen replacement Demo Kit
12VAC/VDC, including 1 ZLED-PCB1
ZLED-PCB1
ZLED-PCB2
Test PCB with one 3W white High Brightness (HB) LED,
cascadable to one multiple LED string
Printed Circuit Board (PCB)
Printed Circuit Board (PCB)
10 unpopulated test PCBs for modular LED string with
footprints of 9 common HB LED types
.
Corporate Headquarters
Sales
Tech Support
www.IDT.com/go/support
6024 Silver Creek Valley Road
San Jose, CA 95138
www.IDT.com
1-800-345-7015 or 408-284-8200
Fax: 408-284-2775
www.IDT.com/go/sales
DISCLAIMER Integrated Device Technology, Inc. (IDT) reserves the right to modify the products and/or specifications described herein at any time, without notice, at IDT's sole discretion. Performance
specifications and operating parameters of the described products are determined in an independent state and are not guaranteed to perform the same way when installed in customer products. The
information contained herein is provided without representation or warranty of any kind, whether express or implied, including, but not limited to, the suitability of IDT's products for any particular purpose, an
implied warranty of merchantability, or non-infringement of the intellectual property rights of others. This document is presented only as a guide and does not convey any license under intellectual property
rights of IDT or any third parties.
IDT's products are not intended for use in applications involving extreme environmental conditions or in life support systems or similar devices where the failure or malfunction of an IDT product can be
reasonably expected to significantly affect the health or safety of users. Anyone using an IDT product in such a manner does so at their own risk, absent an express, written agreement by IDT.
Integrated Device Technology, IDT and the IDT logo are trademarks or registered trademarks of IDT and its subsidiaries in the United States and other countries. Other trademarks used herein are the
property of IDT or their respective third party owners. For datasheet type definitions and a glossary of common terms, visit www.idt.com/go/glossary. All contents of this document are copyright of Integrated
Device Technology, Inc. All rights reserved.
© 2016 Integrated Device Technology, Inc.
2
April 20, 2016
ZLED7000 Datasheet
Contents
1
IC Characteristics.......................................................................................................................................................... 5
1.1
Absolute Maximum Ratings ................................................................................................................................... 5
Operating Conditions............................................................................................................................................. 5
Electrical Parameters............................................................................................................................................. 5
Characteristic Operating Curves............................................................................................................................ 7
1.2
1.3
1.4
2
Circuit Description......................................................................................................................................................... 9
2.1
Voltage Supply....................................................................................................................................................... 9
ZLED7000 Standby Mode...................................................................................................................................... 9
Output Current Control........................................................................................................................................... 9
Output Current and RS.................................................................................................................................... 9
PWM Control ................................................................................................................................................ 10
External DC Voltage Control of Output Current............................................................................................ 10
Microcontroller LED Control.......................................................................................................................... 11
2.2
2.3
2.3.1
2.3.2
2.3.3
2.3.4
3
4
Application Circuit Design ........................................................................................................................................... 12
3.1
External Component – Inductor L1 ...................................................................................................................... 12
External Component – Capacitor C1 ................................................................................................................... 13
External Component – Diode D1 ......................................................................................................................... 13
Output Ripple....................................................................................................................................................... 14
3.2
3.3
3.4
Operating Conditions................................................................................................................................................... 15
4.1
Thermal Conditions.............................................................................................................................................. 15
Thermal Shut-Down Protection............................................................................................................................ 15
Open-Circuit Protection........................................................................................................................................ 15
4.2
4.3
5
6
7
ESD/Latch-Up-Protection............................................................................................................................................ 15
Pin Configuration and Package................................................................................................................................... 16
Layout Requirements.................................................................................................................................................. 17
7.1
Layout Considerations for ADJ (Pin 3)................................................................................................................. 17
Layout Considerations for LX (Pin 1)................................................................................................................... 17
Layout Considerations for VIN (Pin 5) and the External Decoupling Capacitor (C1)............................................. 17
Layout Considerations for GND (Pin 2)................................................................................................................ 17
Layout Considerations for High Voltage Traces................................................................................................... 17
Layout Considerations for the External Coil (L1) ................................................................................................. 17
Layout Considerations for the External Current Sense Resistor (RS) .................................................................. 17
7.2
7.3
7.4
7.5
7.6
7.7
8
9
Ordering Information ................................................................................................................................................... 17
Document Revision History......................................................................................................................................... 18
© 2016 Integrated Device Technology, Inc.
3
April 20, 2016
ZLED7000 Datasheet
List of Figures
Figure 2.1
Figure 2.2
Figure 2.3
Figure 3.1
Figure 6.1
Directly Driving ADJ Input with a PWM Control Signal................................................................................. 10
External DC Control Voltage at ADJ Pin ...................................................................................................... 10
Driving ADJ Input from a Microcontroller...................................................................................................... 11
Output Ripple Reduction .............................................................................................................................. 14
Pin Configuration and Package Drawing SOT89-5 ...................................................................................... 16
List of Tables
Table 1.1
Table 1.2
Table 1.3
Table 4.1
Table 4.2
Absolute Maximum Ratings............................................................................................................................ 5
Operating Conditions...................................................................................................................................... 5
Electrical Parameters ..................................................................................................................................... 5
Pin Description SOT89-5.............................................................................................................................. 16
Package Dimensions SOT89-5 .................................................................................................................... 16
© 2016 Integrated Device Technology, Inc.
4
April 20, 2016
ZLED7000 Datasheet
1
IC Characteristics
1.1
Absolute Maximum Ratings
Table 1.1
No.
Absolute Maximum Ratings
PARAMETER SYMBOL
Input voltage
CONDITIONS
MIN
-0.3
VIN - 5
0
TYP
MAX
50
UNIT
1.1.1
VIN
V
V
V
V
VIN > 5V
VIN + 0.3
VIN + 0.3
50
1.1.2
ISENSE voltage
VISENSE
VIN < 5V
-0.3
1.1.3
1.1.4
1.1.5
1.1.6
1.1.7
1.1.8
LX output voltage
VLX
VADJ
ILX
Adjust pin input voltage
Switch output current
Power dissipation
-0.3
6
V
SOT89-5
SOT89-5
900
1200
150
150
mA
mW
°C
Ptot
Storage temperature
Junction temperature
TST
-55
Tj MAX
°C
1.2
Operating Conditions
Table 1.2
No.
Operating Conditions
PARAMETER
SYMBOL
TOP
CONDITIONS
MIN
-40
6
TYP
MAX
+85
40
UNIT
°C
1.2.1
Operating temperature
Input voltage
1.2.2
VIN
V
1.3
Electrical Parameters
Production testing is at 25°C. At other temperatures within the specified operating range, functional operation of
the chip and specified parameters are guaranteed by characterization, design, and process control.
Test conditions are Tamb = 25°C; VIN = 12V except as noted.
Table 1.3
Electrical Parameters
No.
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNIT
Quiescent supply current
with output off
1.3.1
1.3.2
1.3.3
IINQoff
ADJ pin grounded
40
60
80
μA
Quiescent supply current
with output switching
IINQon
ADJ pin floating
450
95
600
101
μA
Mean current sense
threshold voltage
VSENSE
91
mV
1.3.4
1.3.5
Sense threshold hysteresis
ISENSE pin input current
VSENSEHYS
ISENSE
±15
8
%
VSENSE = 0.1V
10
μA
Measured on ADJ pin with
pin floating
1.3.6
Internal reference voltage
VREF
1.2
V
© 2016 Integrated Device Technology, Inc.
5
April 20, 2016
ZLED7000 Datasheet
No.
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNIT
External control voltage
range on ADJ pin for DC
brightness control
1.3.7
VADJ
0.3
1.2
V
DC voltage on ADJ pin to
switch chip from active (ON)
state to quiescent (OFF)
state
1.3.8
1.3.9
VADJoff
VADJ falling
VADJ rising
0.15
0.2
0.2
0.25
0.3
V
V
DC voltage on ADJ pin to
switch chip from quiescent
(OFF) state to active (ON)
state
VADJon
0.25
Resistance between ADJ
pin and VREF
1.3.10
1.3.11
RADJ
500
kΩ
Continuous LX switch
current
ILXmean
0.65
0.75
A
1.3.12
1.3.13
LX switch leakage current
LX Switch ON resistance
ILX(leak)
RLX
1
μA
Ω
0.9
1.5
PWM frequency =100Hz
PWM amplitude=5V,
VIN=15V, L=27μH, driving
1 LED
Brightness control range at
low frequency PWM signal
1.3.14
DPWM(LF)
1200:1
PWM frequency =10kHz
PWM amplitude=5V,
VIN=15V, L=27μH, driving
1 LED
Brightness control range at
high frequency PWM signal
1.3.15
1.3.16
DPWM(HF)
13:1
154
ADJ pin floating L=100μH
(0.82Ω) IOUT=350mA @
VLED=3.4V, driving 1 LED
Operating frequency
fLX
kHz
1.3.17
1.3.18
Minimum switch ON time
Minimum switch OFF time
TONmin
LX switch ON
LX switch OFF
200
200
ns
ns
TOFFmin
Recommended maximum
operating frequency
1.3.19
1.3.20
fLXmax
1
MHz
Recommended duty cycle
range of output switch at
fLXmax
DLX
0.2
0.8
Internal comparator
propagation delay
1.3.21
1.3.22
1.3.23
TPD
TSD
50
140
20
ns
°C
°C
Thermal shutdown
temperature
Thermal shutdown
hysteresis
TSD-HYS
© 2016 Integrated Device Technology, Inc.
6
April 20, 2016
ZLED7000 Datasheet
1.4
Characteristic Operating Curves
The curves are valid for the typical application circuit and Tamb = 25°C unless otherwise noted.
© 2016 Integrated Device Technology, Inc.
7
April 20, 2016
ZLED7000 Datasheet
© 2016 Integrated Device Technology, Inc.
8
April 20, 2016
ZLED7000 Datasheet
2
Circuit Description
The ZLED7000 is an inductive step-down converter for driving LEDs. It operates in continuous mode, enabling proper LED
current control. The ZLED7000 supports linear or PWM control of the LED current. Only a few external components are
needed for typical applications.
2.1
Voltage Supply
The ZLED7000 has an internal regulator that disables the LX output until the voltage supply rises above a start-up
threshold voltage set internally as needed to ensure that the power MOSFET on-resistance is low enough for
proper operation. When the supply voltage exceeds the threshold, the ZLED7000 begins normal operation.
Important: The ZLED7000 must be operated within the operating voltage range specified in Table 1.2 to avoid
conditions that could result in thermal damage to the ZLED7000. Operating with the supply voltage below the
minimum can result in a high switch duty cycle and excessive ZLED7000 power dissipation, risking over-
temperature conditions (also see section 4.1 regarding thermal restrictions) that could result in activation of the
ZLED7000’s thermal shut-down circuitry. With multiple LEDs, the forward drop is typically adequate to prevent the
chip from switching below the minimum voltage supply specification (6V), so there is less risk of thermal shut-
down.
2.2
ZLED7000 Standby Mode
Whenever the ADJ pin voltage falls below 0.2V, the ZLED7000 turns the output off and the supply current drops
to approximately 60μA. This standby mode minimizes current consumption.
2.3
Output Current Control
The LED control current output on the LX pin is determined by the value of external components and the control
voltage input at the ADJ pin. Selection of the external component RS is discussed below, and other external
components are discussed in section 2.3.4. The subsequent sections describe the two options for control voltage
input at the ADJ pin: a pulse width modulation (PWM) control signal or a DC control voltage.
The ADJ pin has an input impedance† of 500kΩ ±25%.
2.3.1
The current sense threshold voltage and the value of the external current sense resistor (RS) between VIN and
SENSE set the output current through the LEDs (IOUT). Equation (1) below shows this basic relationship. Unless the
Output Current and RS
I
ADJ pin is driven from an external voltage (see section 2.3.3), the minimum value for RS is 0.13 Ω to prevent
exceeding the maximum switch current (see Table 1.1).
95mV
IOUT
=
(1)
RS
Where
IOUT = Nominal average output current through the LED(s)
RS ≥0.13Ω
† At room temperature.
© 2016 Integrated Device Technology, Inc.
9
April 20, 2016
ZLED7000 Datasheet
2.3.2
PWM Control
The output current on LX can be set to a value below the nominal average value determined by resistor RS by
using an external PWM signal as the control signal applied to the ADJ pin. This control signal must be capable of
driving the ZLED7000’s internal 500kΩ pull-up resistor. See Figure 2.1 for an illustration. The minimum signal
voltage range is 0V to 1.8V; the maximum voltage range is 0V to 5V. See Table 1.3 for the specifications for the
signal’s duty cycle DPWM. Any negative spikes on the control signal could interfere with current control or proper
operation of the ZLED7000.
Figure 2.1
Directly Driving ADJ Input with a PWM Control Signal
ZLED7000
1.8V to 5V
0V
ADJ
GND
PWM
2.3.3
External DC Voltage Control of Output Current
The output current on LX can be set to a value below the nominal average value determined by resistor RS by
using an external DC voltage VADJ (0.3 V ≤ VADJ ≤ 1.2V) to drive the voltage at the ADJ pin. This allows adjusting
the output current from 25% to 100% of IOUTnom. See Figure 2.2 for an illustration. The output current can be
calculated using equation (2). If VADJ matches or exceeds VREF (1.2V), the brightness setting is clamped at its
maximum (100%).
Figure 2.2
External DC Control Voltage at ADJ Pin
ZLED7000
ADJ
GND
DC
0.079∗VADJ
IOUT _ DC
=
RS
(2)
Where
IOUT_DC = Nominal average output current through the LED(s) with a DC control voltage
VADJ = External DC control voltage: 0.3 V ≤ VADJ ≤ 1.2V
RS ≥0.13Ω
© 2016 Integrated Device Technology, Inc.
10
April 20, 2016
ZLED7000 Datasheet
2.3.4
Microcontroller LED Control
A microcontroller’s open-drain output can control current to the LED(s) by outputting a PWM control signal to the
ADJ input of the ZLED7000. See Figure 2.1 for an example circuit.
Figure 2.3
Driving ADJ Input from a Microcontroller
ZLED7000
10k
ADJ
MC
GND
© 2016 Integrated Device Technology, Inc.
11
April 20, 2016
ZLED7000 Datasheet
3
Application Circuit Design
The following sections cover selection of the external components shown in the typical application illustrated on
page 1.
3.1
External Component – Inductor L1
Select the inductor value for L1 as needed to ensure that switch on/off times are optimized across the load current
and supply voltage ranges. Select a coil that has a continuous current rating above the required average output
current to the LEDs and a saturation current exceeding the peak output current. Recommendation: Use inductors
in the range of 15μH to 220μH with saturation current greater than 1A for 700mA output current or saturation
current greater than 500mA for 350mA output current. For higher supply voltages with low output current, select
higher values of inductance, which result in a smaller change in output current across the supply voltage range
(refer to the graphs in section 1.4). See section 7.6 for layout restrictions.
Equations (3) and (4) illustrate calculating the timing for LX switching for the example application circuit shown on
page 2. As given in Table 1.3, the minimum period for TON is 200ns; the minimum period for TOFF is also 200ns.
LX Switch OFF Time TOFF in s
Where
L ∗∆I
VLED +VD + IAVG
TOFF
=
(3)
(4)
L
Coil inductance in H
∗
(
RS + rL
)
∆I
Coil peak-peak ripple current in A *
Total LED forward voltage in V
VLED
VD
Diode forward voltage at the
required load current in V
LX Switch ON Time TON in s
IAVG
RS
Required average LED current in A
External current sense resistance in Ω
Coil resistance in Ω
L∗∆I
TON
=
VIN −VLED − IAVG
∗
(
RS + rL + RLX
)
rL
VIN
RLX
Supply voltage in V
Switch resistance in Ω
* With the ZLED7000, the current ripple ∆I is internally set to an appropriate value of 0.3 IAVG
.
*
The inductance value has an equivalent effect on Ton and Toff and therefore affects the switching frequency. For
the same reason, the inductance has no influence on the duty cycle for which the relation of the summed LED
forward voltages n VF to the input voltage VIN is a reasonable approximation. Because the input voltage is a
factor in the ON time, variations in the input voltage affect the switching frequency and duty cycle.
© 2016 Integrated Device Technology, Inc.
12
April 20, 2016
ZLED7000 Datasheet
The following calculation example yields an operating frequency of 122kHz and a duty cycle of 0.33:
Input data: VIN=12V, L=220μH, rL=0.48Ω, VLED=3.4V, IAVG =333mA and VD =0.36V
220µH ∗0.3∗0.333A
TOFF
=
= 5.47µs
(5)
(6)
3.4V + 0.36V + 0.333A∗
(
0.48Ω + 0.3Ω
)
And
220µH ∗0.3∗0.333A
12V − 3.4V − 0.333A∗ 0.3Ω + 0.48Ω + 0.9Ω
TON
=
= 2.73µs
(
)
3.2
External Component – Capacitor C1
To improve system efficiency, use a low-equivalent-series-resistance (ESR) capacitor for input decoupling
because this capacitor must pass the input current AC component. The capacitor value is defined by the target
maximum ripple of the supply voltage; the value is given by equation (7).
IF ∗TON
∆VMAX
CMIN
=
(7)
Where
IF
Value of output current
ΔVMAX Maximum ripple of power supply
TON Maximum ON time of MOSFET
In the case of an AC supply with a rectifier, the capacitor value must be chosen high enough to make sure that
the DC voltage does not drop below the maximum forward voltage of the LED string plus some margin for the
voltage drops across the coil resistance, shunt resistor, and ON resistance of the switching transistor.
Recommendation: Use capacitors with X5R, X7R, or better dielectric for maximum stability over temperature and
voltage. Do not use Y5V capacitors for decoupling in this application. For higher capacitance values, aluminum
electrolytic caps with high switching capability should be used. In this case, improved performance can be
reached by an additional X7R/X5R bypass capacitor of at least 100nF.
3.3
External Component – Diode D1
For the rectifier D1, select a high-speed, low-capacitance Schottky diode with low reverse leakage at the
maximum operating voltage and temperature to ensure maximum efficiency and performance.
Important: Choose diodes with a continuous current rating higher than the maximum output load current and a
peak current rating above the peak coil current. When operating above 85°C, the reverse leakage of the diode
must be addressed because it can cause excessive power dissipation in the ZLED7000.
© 2016 Integrated Device Technology, Inc.
13
April 20, 2016
ZLED7000 Datasheet
Note: Silicon diodes have a greater forward voltage and overshoot caused by reverse recovery time, which can
increase the peak voltage on the LX output. Ensure that the total voltage appearing on the LX pin, including
supply ripple, is within the specified range (see Table 1.1).
3.4
Output Ripple
Shunt a capacitor CLED across the LED(s) as shown in Figure 3.1 to minimize the peak-to-peak ripple current in the
LED if necessary.
Figure 3.1
Output Ripple Reduction
RS
VS
D1
n LED
CLED
VIN
ISENSE
C1
ZLED7000
L1
ADJ
LX
GND
Low ESR capacitors should be used because the efficiency of CLED largely depends on its ESR and the dynamic
resistance of the LED(s). For an increased number of LEDs, using the same capacitor will be more effective.
Lower ripple can be achieved with higher capacitor values, but this will increase start-up delay by reducing the
slope of the LED voltage. The capacitor will not affect operating frequency or efficiency. For a simulation or bench
optimization, CLED values of a few μF are an applicable starting point for the given configuration.
© 2016 Integrated Device Technology, Inc.
14
April 20, 2016
ZLED7000 Datasheet
4
Operating Conditions
4.1
Thermal Conditions
Refer to Table 1.1 for maximum package power dissipation specifications for the ZLED7000’s SOT89-5 package.
Exceeding these specifications due to operating the chip at high ambient temperatures (see Table 1.2 for
maximum operating temperature range) or driving over the maximum load current (see Table 1.1) can damage
the ZLED7000. The ZLED7000 can be used for LED current applications up to750mA when properly mounted to
a high wattage land pattern. Conditions such as operating below the minimum supply voltage or inefficiency of the
circuit due to improper coil selection or excessive parasitic capacitance on the output can cause excessive chip
power dissipation.
4.2
Thermal Shut-Down Protection
The ZLED7000 includes an on-board temperature sensing circuit which stops the output if the junction exceeds
approximately 160°C.
4.3
Open-Circuit Protection
The ZLED7000 is inherently protected if there is an open-circuit in the connection to the LEDs because in this
case, the coil is isolated from the LX pin. This prevents any back EMF from damaging the internal switch due to
forcing the drain above its breakdown voltage.
5
ESD/Latch-Up-Protection
All pins have an ESD protection of >± 2000V according to the Human Body Model (HBM) except for pin 1, which
has a protection level of >± 1000V. The ESD test follows the Human Body Model with 1.5 kΩ/100 pF based on
MIL 883-G, Method 3015.7
Latch-up protection of >± 100mA has been proven based on JEDEC No. 78A Feb. 2006, temperature class 1.
© 2016 Integrated Device Technology, Inc.
15
April 20, 2016
ZLED7000 Datasheet
6
Pin Configuration and Package
Figure 6.1
Pin Configuration and Package Drawing SOT89-5
D
A
D1
1
2
5
4
LX
VIN
E1
E
GND
ADJ
Thermal Pad
ISENSE
b1
3
L
e
b
c
e1
Table 4.1
Pin Description SOT89-5
Pin Name No.
Description
LX
GND
1
2
3
4
Power switch drain
Ground (0V)—see section 7.4 for layout considerations
Output current control pin—see section 2.3 for details
ADJ
ISENSE
Nominal average output current is set by the value of a resistor RS connected from ISENSE to VIN – see
section 2.3.1 for details
VIN
5
Supply voltage (6V to 40V)—see section 7.3 for layout considerations
Table 4.2
Package Dimensions SOT89-5
Dimension (mm)
Dimension (mm)
Symbol
Symbol
Min
Max
Min
Max
2.600
4.250
A
b
1.400
0.320
0.360
0.350
4.400
1.400
1.600
0.520
0.560
0.440
4.600
1.800
E
E1
e
2.300
3.940
b1
c
1.500 Typ
e1
L
2.900
0.900
3.100
1.100
D
D1
The SOT89-5 package has a thermal resistance (junction to ambient) of RθJA = 45 K/W.
© 2016 Integrated Device Technology, Inc.
16
April 20, 2016
ZLED7000 Datasheet
7
Layout Requirements
7.1
Layout Considerations for ADJ (Pin 3)
For applications in which the ADJ pin is unconnected, minimize the length of circuit board traces connected to
ADJ to reduce noise coupling through this high impedance input.
7.2
Layout Considerations for LX (Pin 1)
Minimize the length of circuit board traces connected to the LX pin because it is a fast switching output.
7.3
Layout Considerations for VIN (Pin 5) and the External Decoupling Capacitor (C1)
The C1 input decoupling capacitor must be placed as close as possible to the VIN pin to minimize power supply
noise, which can reduce efficiency. See section 3.2 regarding capacitor selection.
7.4
Layout Considerations for GND (Pin 2)
The ZLED7000 GND (ground) pin must be soldered directly to the circuit board’s ground plane to minimize
ground bounce due to fast switching of the LX pin.
7.5
Layout Considerations for High Voltage Traces
Avoid laying out any high voltage traces near the ADJ pin to minimize the risk of leakage in cases of board
contamination, which could raise the ADJ pin voltage resulting in unintentional output current. Leakage current
can be minimized by laying out a ground ring around the ADJ pin.
7.6
Layout Considerations for the External Coil (L1)
The L1 coil must be placed as close as possible to the chip to minimize parasitic resistance and inductance,
which can reduce efficiency. The connection between the coil and the LX pin must be low resistance.
7.7
Layout Considerations for the External Current Sense Resistor (RS)
Any trace resistance in series with RS must be taken into consideration when selecting the value for RS.
8
Ordering Information
Product Sales Code
Description
ZLED7000 – 40V LED Driver
Package
SOT89-5 (Tape & Reel)
Kit
ZLED7000ZI1R
ZLED7000KIT-D1
ZLED7000 used in a MR16 Halogen replacement Demo
Kit 12VAC/VDC, including 1 ZLED-PCB1
ZLED-PCB1
ZLED-PCB2
Test PCB with one 3W white High Brightness (HB) LED,
cascadable to one multiple LED string
Printed Circuit Board (PCB)
Printed Circuit Board (PCB)
10 unpopulated test PCBs for modular LED string with
footprints of 9 common HB LED types
© 2016 Integrated Device Technology, Inc.
17
April 20, 2016
ZLED7000 Datasheet
9
Document Revision History
Revision
1.0
Date
Description
June 10, 2010
August 12, 2010
April 20, 2016
Production release version
1.1
Revision to equation (5) for Toff. Update for contact information.
Changed to IDT branding.
Corporate Headquarters
Sales
Tech Support
www.IDT.com/go/support
6024 Silver Creek Valley Road
San Jose, CA 95138
www.IDT.com
1-800-345-7015 or 408-284-8200
Fax: 408-284-2775
www.IDT.com/go/sales
DISCLAIMER Integrated Device Technology, Inc. (IDT) reserves the right to modify the products and/or specifications described herein at any time, without notice, at IDT's sole discretion. Performance
specifications and operating parameters of the described products are determined in an independent state and are not guaranteed to perform the same way when installed in customer products. The
information contained herein is provided without representation or warranty of any kind, whether express or implied, including, but not limited to, the suitability of IDT's products for any particular purpose, an
implied warranty of merchantability, or non-infringement of the intellectual property rights of others. This document is presented only as a guide and does not convey any license under intellectual property
rights of IDT or any third parties.
IDT's products are not intended for use in applications involving extreme environmental conditions or in life support systems or similar devices where the failure or malfunction of an IDT product can be
reasonably expected to significantly affect the health or safety of users. Anyone using an IDT product in such a manner does so at their own risk, absent an express, written agreement by IDT.
Integrated Device Technology, IDT and the IDT logo are trademarks or registered trademarks of IDT and its subsidiaries in the United States and other countries. Other trademarks used herein are the
property of IDT or their respective third party owners. For datasheet type definitions and a glossary of common terms, visit www.idt.com/go/glossary. All contents of this document are copyright of Integrated
Device Technology, Inc. All rights reserved.
© 2016 Integrated Device Technology, Inc.
18
April 20, 2016
相关型号：
©2020 ICPDF网 联系我们和版权申明