A Product Line of
Diodes Incorporated
ZXLD1350Q
AUTOMOTIVE GRADE 350mA BUCK LED DRIVER
Description
Pin Assignments
The ZXLD1350Q is a hysteretic mode inductive step-down converter
with integrated switch and high side current sense.
It operates from an input supply from 7V to 30V driving single or
multiple series connected LEDs efficiently external adjustable output
current up to 350mA.
VIN
LX
GND
The output current can be adjusted by applying a DC voltage or a
PWM waveform. 100:1 adjustment of output current is possible using
PWM control. Applying a voltage of 0.2V or lower to the ADJ pin
turns the output off and switches the device into a low current
standby state.
The ZXLD1350Q has been qualified to AECQ100 grade 2 and is
Automotive Grade supporting PPAPs.
ADJ
ISENSE
TSOT23-5
Top View
Features
Simple low parts count
Internal 30V NDMOS switch
Internal PWM filter
High efficiency (up to 95% (Note 1)
Wide input voltage range: 7V to 30V
40V transient capability
Up to 1MHz switching frequency
Typical 4% output current accuracy
Green Molding (No Br, Sb) in TSOT25
Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
Halogen and Antimony Free. “Green” Device (Note 3)
Automotive Grade
Qualified to AEC-Q100 Standards for High Reliability
Supports PPAP Documents (Note 4)
Notes: 1.
2.
3.
4.
No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
See http://www.diodes.com/quality/lead_free.html for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free,
"Green" and Lead-free.
Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl)
and <1000ppm antimony compounds.
Automotive products are AEC-Q100 qualified and are PPAP capable. Automotive, AEC-Q100 and standard products are electrically and thermally
the same, except where specified. For more information, please refer to http://www.diodes.com/quality/product_compliance_definitions/.
Typical Application Circuit
VIN
7~30V
RS
L1
0.33
47µH
VIN
C1
1µF
ADJ
LX
SET
ZXLD1350
GND
GND
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Block Diagram
RS
VIN
L1
D1
VIN
VIN
ISENSE
LX
R1
Current sense circuit
Voltage
regulator
5V
+
Shutdown
circuit
C1
Comparator
+
ADJ
200k
Vref
1.25V
4KHz
MN
R2
R3
GND
Figure 1. Block diagram – Pin Connection
Pin Description
Name
LX
GND
Pin No.
1
2
ADJ
3
ISENSE
4
VIN
5
Description
Drain of NDMOS switch
Ground (0V)
Multi-function On/Off and brightness control pin:
Leave floating for normal operation
VADJ = VREF =1.25V giving nominal average output current IOUTnom=0.1/RS)
Drive to voltage below 0.2V to turn off output current.
Drive with Analog voltage:
0.3V<VADJ<2.5V adjusts output current from 25% to 200%(†) of IOUTnom
Drive with PWM signal from open-collector or open-drain transistor, to adjust output current.
Adjustment range 25% to 100% of IOUTnom for f>10kHz and 1% to 100% of IOUTnom for f<500Hz
Connect a capacitor from this pin to ground to increase soft-start time. (Default soft-start time=0.5ms.
Additional soft-start time is approx.0.5ms/nF)
Connect resistor RS from this to VIN to define nominal average output current IOUTnom=0.1/RS
(Note: RSMIN=0.27V with ADJ pin open circuit)
Input voltage (7V to 30V). Decouple to ground with 1µF of higher X7R ceramic capacitor close to device
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ZXLD1350Q
Absolute Maximum Ratings (Voltages to GND Unless Otherwise Stated)
Symbol
Parameter
VIN
Input Voltage
VSENSE
ISENSE Voltage
VLX
LX Output Voltage
VADJ
Adjust Pin Input Voltage
ILX
Rating
-0.3 to +30
+0.3 to -5
-0.3 to +30
V
(40V for 0.5 sec)
(Refer to Package thermal de-rating curve on page 17)
Storage Temperature
TJ MAX
Junction Temperature
ESD Susceptibility
HBM
Human Body Model
CDM
Charged Device Model
MM
Machine Model
Caution:
V
(measured with respect to VIN)
Power Dissipation
TST
V
(40V for 0.5 sec)
Switch Output Current
PTOT
Unit
-0.3 to +6
V
500
mA
450
mW
-55 to 150
°C
150
°C
500
1000
100
V
V
Stresses greater than the 'Absolute Maximum Ratings' specified above, may cause permanent damage to the device. These are stress ratings
only; functional operation of the device at conditions between maximum recommended operating conditions and absolute maximum ratings is not
implied. Device reliability may be affected by exposure to absolute maximum rating conditions for extended periods of time.
(Semiconductor devices are ESD sensitive and may be damaged by exposure to ESD events. Suitable ESD precautions should be taken when
handling and transporting these devices.)
Thermal Resistance
Symbol
Parameter
Rating
Unit
JA
Junction to Ambient
200
°C/W
Recommended Operating Conditions
Symbol
VIN
Parameter
Min
Input voltage
Typ.
7
Max
Units
30
V
tOFFMIN
Minimum switch off-time
800
ns
tONMIN
Minimum switch on-time
800
ns
DLX
Duty cycle range
0.01
0.99
TA
Ambient operating temperature range
-40
+105
°C
0.37
A
1
MHz
ILX_CONT
fLXmax
TPD
Average/RMS LX switch current
Recommended maximum operating frequency
Internal comparator propagation delay
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ZXLD1350Q
Electrical Characteristics
Symbol
VSU
IINQoff
IINQon
VSENSE
(Test conditions: VIN = 12V, Tamb = +25°C, unless otherwise specified.)
Parameter
Min.
Typ.
Internal regulator start-up threshold
VIN rising
Condition
—
4.8
—
V
Quiescent supply current with output off
ADJ pin grounded
—
15
20
µA
Quiescent supply current with output switching
ADJ pin floating, f = 250kHz
—
250
500
µA
Mean current sense threshold voltage
Measured on ISENSE pin with
respect to VIN
95
100
105
mV
(Defines LED current setting accuracy)
Max.
Unit
VADJ = 1.25V
VSENSEHYS
Sense threshold hysteresis
—
—
±15
—
%
ISENSE
ISENSE pin input current
VSENSE = VIN -0.1
—
1.25
10
µA
VREF
Internal reference voltage
Measured on ADJ pin with pin
floating
1.21
1.25
1.29
V
VREF/T
Temperature coefficient of VREF
—
—
50
—
ppm/°C
VADJ
External control voltage range on ADJ pin for DC
brightness control (Note 5)
—
0.3
—
2.5
V
VADJoff
DC voltage on ADJ pin to switch device from active (on)
VADJ falling
state to quiescent (off) state
0.15
0.2
0.25
V
VADJon
DC voltage on ADJ pin to switch device from quiescent
VADJ rising
(off) state to active (on) state
0.2
0.25
0.3
V
RADJ
Resistance between ADJ pin and VREF
—
135
—
250
kΩ
ILXmean
Continuous LX switch current
—
—
—
0.37
A
RLX
LX switch ‘On’ resistance
—
—
1.5
2
Ω
ILX(leak)
LX switch leakage current
—
—
—
1
µA
DPWM(LF)
Duty cycle range of PWM signal applied to ADJ pin
during low frequency PWM dimming mode
PWM frequency <500Hz PWM
amplitude = VREF
0.01
—
1
—
Brightness control range
Measured on ADJ pin
—
100:1
—
—
Duty cycle range of PWM signal applied to ADJ pin
during high frequency PWM dimming mode
PWM frequency <10kHz PWM
amplitude = VREF
0.16
—
1
—
Brightness control range
Measured on ADJ pin
—
5:1
—
—
—
250
—
kHz
—
500
—
µs
DPWM(HF)
ADJ pin floating
fLX
Operating frequency
L = 100H (0.82V)
(See graphs for more details)
IOUT = 350ma @ VLED = 3.4V
Driving 1 LED
Start up time
tSS
Note:
(See graphs for more details)
Time taken for output current to
reach 90% of final value after
voltage on ADJ pin has risen
above 0.3V.
5. 100% brightness corresponds to VADJ = VADJ(nom) = VREF. Driving the ADJ pin above VREF will increase the VSENSE threshold and output current
proportionally.
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Device Description
The device, in conjunction with the coil (L1) and current sense resistor (RS), forms a self-oscillating continuous-mode buck converter.
Device operation (Refer to block diagram and Figure 1 - Operating waveforms)
Figure 1. Theoretical Operating Waveforms
Operation can be best understood by assuming that the ADJ pin of the device is unconnected and the voltage on this pin (V ADJ) appears
directly at the (+) input of the comparator.
When input voltage VIN is first applied, the initial current in L1 and RS is zero and there is no output from the current sense circuit. Under this
condition, the (-) input to the comparator is at ground and its output is high. This turns MN on and switches the LX pin low, causing current to
flow from VIN to ground, via RS, L1 and the LED(s). The current rises at a rate determined by VIN and L1 to produce a voltage ramp (VSENSE)
across RS. The supply referred voltage VSENSE is forced across internal resistor R1 by the current sense circuit and produces a proportional
current in internal resistors R2 and R3. This produces a ground referred rising voltage at the (-) input of the comparator. When this reaches
the threshold voltage (VADJ), the comparator output switches low and MN turns off. The comparator output also drives another NMOS switch,
which bypasses internal resistor R3 to provide a controlled amount of hysteresis. The hysteresis is set by R3 to be nominally 15% of V ADJ.
When MN is off, the current in L1 continues to flow via D1 and the LED(s) back to V IN. The current decays at a rate determined by the LED
and diode forward voltages to produce a falling voltage at the input of the comparator. When this voltage returns to V ADJ, the comparator
output switches high again. This cycle of events repeats, with the comparator input ramping between limits of V ADJ ± 15%.
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Device Description (Continued)
Switching thresholds
With VADJ =VREF, the ratios of R1, R2 and R3, define an average V SENSE switching threshold of 100mV (measured on the I SENSE pin with
respect to VIN). The average output current IOUTnom is then defined by this voltage and Rs according to:
IOUTnom=100mV/RS
Nominal ripple current is ±15mV/RS
Adjusting output current
The device contains a low pass filter between the ADJ pin and the threshold comparator and an internal current limiting resistor (200k nom)
between ADJ and the internal reference voltage. This allows the ADJ pin to be overdriven with either DC or pulse signals to change the
VSENSE switching threshold and adjust the output current. The filter is third order, comprising three sections, each with a cut-off frequency of
nominally 4kHz.
Details of the different modes of adjusting output current are given in the applications section.
Output shutdown
The output of the low pass filter drives the shutdown circuit. When the input voltage to this circuit falls below the threshold (0.2V nom), the
internal regulator and the output switch are turned off. The voltage reference remains powered during shutdown to provide the bias current
for the shutdown circuit. Quiescent supply current during shutdown is nominally 15mA and switch leakage is below 1mA.
Typical Operating Waveforms [VIN = 12V, RS = 0.3V, L = 100 μH]
Normal operation. Output current (Ch3) and LX voltage (Ch1)
ZXLD1350Q
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Start-up waveforms. Output current (Ch3), LX voltage (Ch1) and
VADJ (Ch2)
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Typical Operating Conditions
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Typical Characteristics (Continued)
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Typical Characteristics (Continued)
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Application Information
Setting nominal average output current with external resistor RS
The nominal average output current in the LED(s) is determined by the value of the external current sense resistor (R S) connected between
VIN and ISENSE and is given by:
IOUTnom = 0.1/RS [for RS 0.27Ω]
The table below gives values of nominal average output current for several preferred values of current setting resistor (RS) in the typical
application circuit shown on page 1:
RS(Ω)
0.27
0.30
0.33
0.39
Nominal average output
current (mA)
370
333
300
256
The above values assume that the ADJ pin is floating and at a nominal voltage of VREF (=1.25V). Note that RS = 0.27V is the minimum
allowed value of sense resistor under these conditions to maintain switch current below the specified maximum value.
It is possible to use different values of RS if the ADJ pin is driven from an external voltage. (See next section).
Output current adjustment by external DC control voltage
The ADJ pin can be driven by an external dc voltage (V ADJ), as shown, to adjust the output current to a value above or below the nominal
average value defined by RS.
+
ZXLD1350
ADJ
GND
DC
GND
The nominal average output current in this case is given by:
IOUTdc = 0.08*VADJ /RS
for 0.3 < VADJ < 2.5V
Note that 100% brightness setting corresponds to V ADJ = VREF. When driving the ADJ pin above 1.25V, RS must be increased in proportion
to prevent IOUTdc exceeding 370mA maximum.
The input impedance of the ADJ pin is 200kΩ ±25%.
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Application Information (Continued)
Output Current Adjustment by PWM Control
Directly driving ADJ input
A Pulse Width Modulated (PWM) signal with duty cycle DPWM can be applied to the ADJ pin, as shown below, to adjust the output current to
a value above or below the nominal average value set by resistor RS:
PWM
VADJ
ADJ
ZXLD1350
GND
0V
GND
Driving the ADJ input via open collector transistor
The recommended method of driving the ADJ pin and controlling the amplitude of the PWM waveform is to use a small NPN switching
transistor as shown below:
ADJ
PWM
ZXLD1350
GND
GND
This scheme uses the 200k resistor between the ADJ pin and the internal voltage reference as a pull-up resistor for the external transistor.
Driving the ADJ input from a microcontroller
Another possibility is to drive the device from the open drain output of a microcontroller. The diagram below shows one method of doing this:
MCU
10k
ADJ
ZXLD1350
GND
The diode and resistor suppress possible high amplitude negative spikes on the ADJ input resulting from the drain-source capacitance of the
FET. Negative spikes at the input to the device should be avoided as they may cause errors in output current, or erratic device operation.
PWM dimming can be further split into high frequency and low frequency PWM dimming and how the device responds to these.
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Application Information (Continued)
Low frequency PWM mode
When the ADJ pin is driven with a low frequency PWM signal (eg 100Hz), with a high level voltage V ADJ and a low level of zero, the output of
the internal low pass filter will swing between 0V and VADJ, causing the input to the shutdown circuit to fall below its turn-off threshold (200mV
nom) when the ADJ pin is low. This will cause the output current to be switched on and off at the PWM frequency, resulting in an average
output current IOUTavg proportional to the PWM duty cycle. (See Figure 2 - Low frequency PWM operating waveforms).
Figure 2. Low frequency PWM operating waveforms
The average value of output current in this mode is given by:
IOUTavg 0.1DPWM/RS for DPWM >0 01
This mode is preferable if optimum LED 'whiteness' is required. It will also provide the widest possible dimming range (approx. 100:1) and
higher efficiency at the expense of greater output ripple.
Note that the low pass filter introduces a small error in the output duty cycle due to the difference between the start-up and shut-down times.
This time difference is a result of the 200mV shutdown threshold and the rise and fall times at the output of the filter. To minimize this error,
the PWM duty cycle should be as low as possible consistent with avoiding flicker in the LED.
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Application Information (Continued)
High frequency PWM mode
At PWM frequencies above 10kHz and for duty cycles above 0.16, the output of the internal low pass filter will contain a DC component that
is always above the shutdown threshold. This will maintain continuous device operation and the nominal average output current will be
proportional to the average voltage at the output of the filter, which is directly proportional to the duty cycle. (See Figure 3 – High frequency
PWM operating waveforms). For best results, the PWM frequency should be maintained above the minimum specified value of 10kHz, in
order to minimize ripple at the output of the filter. The shutdown comparator has approximately 50mV of hysteresis, to minimize erratic
switching due to this ripple. An upper PWM frequency limit of approximately one tenth of the operating frequency is recommended, to avoid
excessive output modulation and to avoid injecting excessive noise into the internal reference.
Figure 3. High Frequency PWM operating waveforms
The nominal average value of output current in this mode is given by:
IOUTnom »0.1DPWM/RS for DPWM >0.16
This mode will give minimum output ripple and reduced radiated emission, but with a reduced dimming range (approx.5:1). The restricted
dimming range is a result of the device being turned off when the DC component on the filter output falls below 200mV.
Shutdown mode
Taking the ADJ pin to a voltage below 0.2V for more than approximately 100μs, will turn off the output and supply current will fall to a low
standby level of 15μA nominal.
Note that the ADJ pin is not a logic input. Taking the ADJ pin to a voltage above V REF will increase output current above the 100% nominal
average value. (See graphs for details).
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Application Information (Continued)
Soft-start
The device has inbuilt soft-start action due to the delay through the PWM filter. An external capacitor from the ADJ pin to ground will provide
additional soft-start delay, by increasing the time taken for the voltage on this pin to rise to the turn-on threshold and by slowing down the rate
of rise of the control voltage at the input of the comparator. With no external capacitor, the time taken for the output to reach 90% of its final
value is approximately 500μs. Adding capacitance increases this delay by approximately 0.5ms/nF.
The graph below shows the variation of soft-start time for different values of capacitor.
Inherent open-circuit LED protection
If the connection to the LED(s) is open-circuited, the coil is isolated from the LX pin of the chip, so the device will not be damaged, unlike in
many boost converters, where the back EMF may damage the internal switch by forcing the drain above its breakdown voltage.
Capacitor selection
A low ESR capacitor should be used for input decoupling, as the ESR of this capacitor appears in series with the supply source impedance
and lowers overall efficiency. This capacitor has to supply the relatively high peak current to the coil and smooth the current ripple on the
input supply. A minimum value of 1μF is acceptable if the input source is close to the device, but higher values will improve performance at
lower input voltages, especially when the source impedance is high. The input capacitor should be placed as close as possible to the IC.
For maximum stability over temperature and voltage, capacitors with X7R, X5R, or better dielectric are recommended. Capacitors with Y5V
dielectric are not suitable for decoupling in this application and should NOT be used.
A table of recommended manufacturers is provided below:
Manufacturer
Website
Murata
www.murata.com
Taiyo Yuden
www.t-yuden.com
Kemet
www.kemet.com
AVX
www.avxcorp.com
Inductor Selection
Recommended inductor values for the ZXLD1350Q are in the range 47µH to 220µH.
Higher values of inductance are recommended at higher supply voltages in order to minimize errors due to switching delays, which result in
increased ripple and lower efficiency. Higher values of inductance also result in a smaller change in output current over the supply voltage
range. (See graphs). The inductor should be mounted as close to the device as possible with low resistance connections to the LX and VIN
pins.
The chosen coil should have a saturation current higher than the peak output current and a continuous current rating above the required
mean output current.
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Application Information (Continued)
Suitable coils for use with the ZXLD1350Q are listed in the table below:
Part No.
DO1608C
MSS6132ML
CD104-MC
NP04SB470M
L
(µH)
47
47
68
100
220
47
DCR
(V)
0.64
0.38
0.58
0.82
0.55
0.27
ISAT
(A)
0.5
0.56
0.47
0.39
0.53
0.38
Manufacturer
CoilCraft
Sumida
Taiyo Yuden
The inductor value should be chosen to maintain operating duty cycle and switch 'on'/'off' times within the specified limits over the supply
voltage and load current range.
The following equations can be used as a guide, with reference to Figure 1 - Operating waveforms.
LX Switch 'On' time
t ON
LI
VIN VLED Iavg R S rL RLX
Note: tONnmin > 200ns
LX Switch 'Off' time
t OFF
LI
VLED VD Iavg R S rL
Note: tOFFmin > 200ns
Where:
L is the coil inductance (H)
rL is the coil resistance ()
Iavg is the required LED current (A)
I is the coil peak-peak ripple current (A) {Internally set to 0.3 x Iavg}
VIN is the supply voltage (V)
VLED is the total LED forward voltage (V)
RLX is the switch resistance ()
VD is the rectifier diode forward voltage at the required load current (V)
Example:
For VIN =12V, L=47µH, rL=0.64V, VLED=3.4V, Iavg =350mA and VD =0.36V
tON = (47e-6 x 0.105)/(12 - 3.4 - 0.672) = 0.622µs
tOFF = (47e-6 x 0.105)/(3.4 + 0.36 + 0.322)= 1.21µs
This gives an operating frequency of 546kHz and a duty cycle of 0.34.
These and other equations are available as a spreadsheet calculator from the Diodes website.
Note that in practice, the duty cycle and operating frequency will deviate from the calculated values due to dynamic switching delays, switch
rise/fall times and losses in the external components.
Optimum performance will be achieved by setting the duty cycle close to 0.5 at the nominal supply voltage. This helps to equalize the
undershoot and overshoot and improves temperature stability of the output current.
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Application Information (Continued)
Diode Selection
For maximum efficiency and performance, the rectifier (D1) should be a fast low capacitance Schottky diode with low reverse leakage at the
maximum operating voltage and temperature. The recommended diode for use with this part is the DFLS140Q. This has approximately ten
times lower leakage than standard Schottky diodes, which are unsuitable for use above 85°C. It also provides better efficiency than silicon
diodes, due to a combination of lower forward voltage and reduced recovery time.
The table below gives the typical characteristics for the DFLS140Q:
Diode
Forward Voltage @
300mA (mV)
DFLS140Q
410
Continuous
Current
(mA)
1000
Reverse Leakage
@ 30V 85°C
(µA)
100
Package
PowerDI®123
If alternative diodes are used, it is important to select parts with a peak current rating above the peak coil current and a continuous current
rating higher than the maximum output load current. It is very important to consider the reverse leakage of the diode when operating above
85°C. Excess leakage will increase the power dissipation in the device.
The higher forward voltage and overshoot due to reverse recovery time in silicon diodes will increase the peak voltage on the LX output. If a
silicon diode is used, care should be taken to ensure that the total voltage appearing on the LX pin including supply ripple, does not exceed
the specified maximum value.
Reducing Output Ripple
Peak to peak ripple current in the LED(s) can be reduced, if required, by shunting a capacitor Cled across the LED(s) as shown below:
RS
VIN
LED
Cled
L1
D1
VIN
ISENSE
LX
ZXLD1350
A value of 1μF will reduce nominal ripple current by a factor three (approx.). Proportionally lower ripple can be achieved with higher capacitor
values. Note that the capacitor will not affect operating frequency or efficiency, but it will increase start-up delay, by reducing the rate of rise
of LED voltage.
Operation at low supply voltage
The internal regulator disables the drive to the switch until the supply has risen above the start-up threshold (VSU). Above this threshold, the
device will start to operate. However, with the supply voltage below the specified minimum value, the switch duty cycle will be high and the
device power dissipation will be at a maximum. Care should be taken to avoid operating the device under such conditions in the application,
in order to minimize the risk of exceeding the maximum allowed die temperature. (See next section on thermal considerations).
Note that when driving loads of two or more LEDs, the forward drop will normally be sufficient to prevent the device from switching below
approximately 6V. This will minimize the risk of damage to the device.
ZXLD1350Q
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ZXLD1350Q
Application Information (Continued)
Thermal considerations
When operating the device at high ambient temperatures, or when driving maximum load current, care must be taken to avoid exceeding the
package power dissipation limits. The graph below gives details for power derating. This assumes the device to be mounted on a (25mm)2
PCB with 1oz copper standing in still air.
Note that the device power dissipation will most often be a maximum at minimum supply voltage. It will also increase if the efficiency of the
circuit is low. This may result from the use of unsuitable coils, or excessive parasitic output capacitance on the switch output.
Thermal compensation of output current
High luminance LEDs often need to be supplied with a temperature compensated current in order to maintain stable and reliable operation at
all drive levels. The LEDs are usually mounted remotely from the device, so for this reason, the temperature coefficients of the internal
circuits for the ZXLD1350Q have been optimized to minimize the change in output current when no compensation is employed. If output
current compensation is required, it is possible to use an external temperature sensing network - normally using Negative Temperature
Coefficient (NTC) thermistors and/or diodes, mounted very close to the LED(s). The output of the sensing network can be used to drive the
ADJ pin in order to reduce output current with increasing temperature.
Layout considerations
LX pin
The LX pin of the device is a fast switching node, so PCB tracks should be kept as short as possible. To minimize ground 'bounce', the
ground pin of the device should be soldered directly to the ground plane.
Coil and decoupling capacitors
It is particularly important to mount the coil and the input decoupling capacitor close to the device to minimize parasitic resistance and
inductance, which will degrade efficiency. It is also important to take account of any track resistance in series with current sense resistor RS.
ADJ pin
The ADJ pin is a high impedance input, so when left floating, PCB tracks to this pin should be as short as possible to reduce noise pickup. A
100nF capacitor from the ADJ pin to ground will reduce frequency modulation of the output under these conditions. An additional series 10kΩ
resistor can also be used when driving the ADJ pin from an external circuit (see below). This resistor will provide filtering for low frequency
noise and provide protection against high voltage transients.
10k
ADJ
ZXLD1350
GND
100nF
GND
High voltage tracks
Avoid running any high voltage tracks close to the ADJ pin, to reduce the risk of leakage due to board contamination. Any such leakage may
raise the ADJ pin voltage and cause excessive output current. A ground ring placed around the ADJ pin will minimize changes in output
current under these conditions.
ZXLD1350Q
Document number: DS37076 Rev. 1 - 2
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Ordering Information
Packing: 7” Tape and Reel
Device
Package
Code
Package
(Note 6)
Part
Mark
Quantity per reel
Tape width
Part Number Suffix
Qualification Grade
(Note 7)
ZXLD1350QET5TA
ET5
TSOT25
1350
3000
8mm
TA
Automotive Grade
Note:
6.
7.
Pad layout as shown on Diodes Inc. suggested pad layout document AP02001, which can be found on our website at
http://www.diodes.com/datasheets/ap02001.pdf.
ZXLD1350Q has been qualified to AEC-Q100 grade 2 and is classified as “Automotive Grade” supporting PPAP documentation.
See ZXLD1350 datasheet for commercial qualified versions.
Marking Information
TSOT25
XXXX : Identification code : 1350
Package Outline Dimensions
Please see AP02002 at http://www.diodes.com/datasheets/ap02002.pdf for latest version.
D
e1
E
E1
L2
c
4x1
e
L
5x b
A
A2
A1
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TSOT25
Dim Min Max Typ
A
1.00
A1 0.01 0.10
A2 0.84 0.90
D
2.90
E
2.80
E1
1.60
b 0.30 0.45
c 0.12 0.20
e
0.95
e1
1.90
L 0.30 0.50
L2
0.25
θ
0°
8°
4°
θ1
4°
12°
All Dimensions in mm
December 2014
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A Product Line of
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ZXLD1350Q
Suggested Pad Layout
Please see AP02001 at http://www.diodes.com/datasheets/ap02001.pdf for the latest version.
C
C
Dimensions Value (in mm)
C
0.950
X
0.700
Y
1.000
Y1
3.199
Y1
Y (5x)
X (5x)
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Copyright © 2014, Diodes Incorporated
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