STCF07
High power buck-boost white LED driver
Datasheet − production data
Features
■
Buck-boost DC-DC converter
■
Drives one power LED up to 1 A in flash mode
■
Drives one power LED up to 800 mA in
continuous mode
■
LED temperature protection
■
Output current control
■
1.8 MHz (typ.) fixed frequency PWM
■
Synchronous rectification
■
High efficiency across the total input voltage
range
■
Operational modes:
– Shutdown mode
– High current mode: up to 1 A
– Low current mode: from 20 mA
■
Adjustable current in both modes
■
Peak inductor limited to 2.3 A (typ.)
■
LED disconnected from the battery in
shutdown mode
■
NTC LED temperature protection
■
Overvoltage protection: 5.3 V
■
Short-circuit protection
■
Overtemperature protection
■
ULVLO function
■
1 µA max shutdown current
■
QFN16 (4 x 4 x 1 mm) 16 leads
Applications
■
Camera flash for mobile phones
■
Power supply for high power LEDs
Table 1.
QFN16 (4 x 4 mm)
Description
The STCF07 is a dedicated, size-optimized
solution for driving a power LED. The device is a
buck-boost converter which guarantees proper
LED current control over all possible battery
voltage and LED forward voltage conditions. The
output current control ensures good current
regulation over the forward voltage spread
characteristics of high-brightness LEDs. The
device includes various functions to protect the
chip and the power LEDs. These include soft-start
control as well as detection and protection of chip
overtemperature and shorted LEDs. An optional
external NTC is supported to protect the LEDs
against overheating. It is possible to separately
program the current intensity in HIGH and LOW
mode using the SEL pin. The device is housed in
a 16-lead QFN16 (4 x 4 mm) package with a
height less than 1 mm.
Device summary
Order code
Package
Packaging
STCF07PNR
QFN16 (4 x 4 mm)
Tape and reel
September 2012
This is information on a product in full production.
Doc ID 16757 Rev 3
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www.st.com
26
Contents
STCF07
Contents
1
Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2
Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3
Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4
Application information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5
Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
6
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
7
Logic pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
8
9
2/26
7.1
CSEL pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
7.2
FAULT pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
7.3
ENABLE pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Detailed description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8.1
Buck-boost converter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8.2
High current mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8.3
Low current mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8.4
Shutdown mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8.5
Soft-start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8.6
STCF07 protection features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
8.6.1
Peak current and short-circuit protection . . . . . . . . . . . . . . . . . . . . . . . . 13
8.6.2
Overvoltage protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
8.6.3
Thermal shutdown protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
8.6.4
Sensing of LED temperature with the NTC resistor . . . . . . . . . . . . . . . . 13
8.6.5
Undervoltage lockout function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
PCB design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
9.1
PCB design rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
9.2
PCB design of the demonstration board . . . . . . . . . . . . . . . . . . . . . . . . . 16
9.3
Schematic of the demonstration board . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Doc ID 16757 Rev 3
STCF07
Contents
10
Typical performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
11
External component selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
11.1
Input and output capacitor selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
11.2
Inductor selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
11.3
LED selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
11.4
RHC selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
11.5
RLC selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
11.6
NTC and RX resistor selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
12
Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
13
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Doc ID 16757 Rev 3
3/26
Block diagram
STCF07
1
Block diagram
Figure 1.
STCF07 block diagram
VLX1B
VLX1A
PVBAT
VLX2
CURRENT
PROTECTION
VOUT
VBAT
GND
ENABLE
CSEL
FAULT
LOGIC
OVER
TEMP
BANDGAP
REF
MX
SOFT
START
FB2
OSC
FB2S
REF
DRIVER
NTC
CONTROL
PNGD
4/26
FB1
RX
Doc ID 16757 Rev 3
NTC
STCF07
Pin configuration
2
Pin configuration
Figure 2.
STCF07 pin connections (top view)
Table 2.
STCF07 pin description
Pin n°
Symbol
Description
1
VLX2
8
RX
2
NTC
3
VOUT
4
FB1
Feedback pin [ILED*(RHC+RLC)]
5
FB2
RTR bypass
6
FB2S
Feedback pin [ILED*RHC]
14
GND
Signal ground
13
CSEL
Current selection
7
EN
16
FAULT
Diagnostic
9
PVBAT
Power supply voltage
10
VBAT
11
VLX1A
Inductor VLX1 connection
12
VLX1B
Inductor VLX1 connection
15
PGND
Power ground
Exposed pad
PGND
To be connected to the PCB ground plane for optimal electrical and
thermal performance
Inductor VLX2 connection
RX resistor connection
NTC resistor connection
Output voltage
Enable
Supply voltage
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5/26
Maximum ratings
STCF07
3
Maximum ratings
Table 3.
Absolute maximum ratings
Symbol
Parameter
Value
Unit
VBAT
Signal supply voltage
-0.3 to 6
V
PVBAT
Power supply voltage
-0.3 to 6
V
VLX1A, VLX1B
Inductor connection 1
-0.3 to VI+0.3
V
VLX2
Inductor connection 2
-0.3 to VI+0.3
V
VOUT
Output voltage
-0.3 to 6
V
Feedback and sense voltage
-0.3 to 3
V
Connection for reference resistor
-0.3 to 3
V
Current selection
-0.3 to VI+0.3
V
Enable
-0.3 to VI+0.3
V
Diagnostic
-0.3 to VI+0.3
V
-0.3 to 3
V
FB1, FB2, FB2S
RX
CSEL
EN
FAULT
NTC
Connection for LED temperature sensing
ESD
Human body model
±2
kV
PTOT
Continuous power dissipation (at TA = 70 °C)
800
mW
TOP
Operating junction temperature range
-40 to 85
°C
Junction temperature
-40 to 150
°C
Storage temperature range
-65 to 150
°C
TJ
TSTG
Note:
Absolute maximum ratings are those values beyond which damage to the device may occur.
Functional operation under these condition is not implied.
Table 4.
Thermal data
Symbol
RthJA (1)
Parameter
Thermal resistance junction-ambient
Value
Unit
31
°C/W
1. Junction-to-ambient thermal resistance in JEDEC still air chamber. Thermal test board JESD51-7 (leaded surface mount
packages).
6/26
Doc ID 16757 Rev 3
STCF07
Application information
4
Application information
Figure 3.
Application schematic diagram
L
VIN
VLX1 VLX1
VLX2
VOUT
PVBAT
LED
VBAT
CIN
FB1
COUT
ENABLE
CSEL
RLC
FB2
FAULT
GND
PGND RX
FB2S
NTC
RHC
NTC
RX
Optional components
Note:
Represents a typical application schematic for an output current of 800 mA (max) in
continuous mode operation. For pulse/flash mode operation it is possible to increase the
maximum output current up to 1 A. If the battery voltage is higher than 3.1 V, the chip is
capable of delivering the maximum output current of up to 1 A in continuos mode.
Table 5.
List of external components
Component
RHC
Manufacturer
Part number
Welwyn
LR1206-R20FI (1)
KOA
SR732BTTDR160F
(2)
Value
Size
0.2 Ω
1206
0.16 Ω
1206
RLC
Tyco Electronics
CRL1220T1R8J
1.8 Ω
0805
CIN
TDK
C1608X5R0J106MT
10 µF
0603
COUT
TDK
C1608X5R0J475M
L
4.7 µF
0603
VLF4014ST-2R2M1R9
(1)
2.2 µH / 1.4 A
3.5x3.8x1.4 mm
VLF5014S-2R2M2R3
(2)
2.2 µH / 2.3 A
4.6x4.8x1.4 mm
TDK
NTC
MURATA
NCP18WF104J03RB
100 kΩ
0805
RX
Tyco Electronics
1-1879132-9
15 kΩ
0402
LED
Luxeon
LXHL_PW09
1. For 800 mA output current performance.
2. For 1000 mA output current performance.
Note:
The above-listed external components refer to a typical application. Operation of the
STCF07 is not limited to the use of these components.
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Electrical characteristics
5
STCF07
Electrical characteristics
TA = 25 °C, VI = 3.6 V, 2 x CI = 10 µF, CO = 1 µF, L = 2.2 µH, RHC = 0.22 Ω, RLC = 1.8 Ω,
RX = 15 kΩ
Table 6.
Symbol
Electrical characteristics
Parameter
VI
Input voltage supply
UVLO
Undervoltage lockout
VPW_ONRESET Power ON reset threshold
IO
Test conditions
Min.
Typ.
2.7
Max.
Unit
5.5
V
VI = 2.7 V
2.2
V
VI rising
2.3
V
Output current - high current CSEL = VI; VI = 2.7 V to 5.5 V;
level
RHC = 0.16 Ω, POUT = 3.4 W
1000
Output current - high current CSEL = VI; VI = 3.2 V to 5.5 V;
RHC = 0.16 Ω, POUT = 4 W
level
1000
mA
5.3
V
Output current - low current
level
CSEL = GND; VI = 3.3 V to 5.5 V;
RHC + RLC ~ 2 Ω
20
VOUT
Regulated voltage range
ILIM
Inductor peak current
VI = 2.7 V, VOUT shorted during
operation
FB1
Feedback voltage
Low current (CSEL = 0 V)
152
160
168
mV
FB2
Feedback voltage
High current (CSEL = VI)
152
160
168
mV
RON_
FB1-FB2 ON resistance
High current (CSEL = VI)
IO = 800 mA
90
mΩ
Quiescent current in
shutdown mode
EN = GND
1
µA
Quiescent current in high
current mode
EN = VI; CSEL = VI; VI = 3.3 V to
5.5 V; RHC = 0.22 Ω
1.8
mA
fs
Frequency
VI = 2.7 V
1.8
MHz
n
Efficiency
VI = 3.2 to 4.2 V, IO = 800 mA
85
%
Output overvoltage
protection
VI = 5.5 V, no load
OVHYST
Overvoltage hysteresis
VI = 5.5 V, no load
0.3
V
OTP
Overvoltage protection
VI = 5.5 V
140
°C
OTHYST
Overvoltage hysteresis
VI = 5.5 V
20
°C
VNTC
NTC voltage reference
VI = 2.7 V to 5.5 V
1.8
V
VRX
NTC voltage threshold
INTC = 1 mA Max
1.2
V
RX-NTC switch OFF leakage
Shutdown mode,
VNTC = 2 V - VRX = GND
IQ
OVP
NTCLEAK
VIL
VIH
8/26
2.5
Input logic signal level CSEL,
VI = 2.7 V to 5.5 V
EN
Doc ID 16757 Rev 3
2.3
A
5.5
V
1
0
0.4
1.4
3
µA
V
STCF07
Table 6.
Symbol
Electrical characteristics
Electrical characteristics (continued)
Parameter
Min.
Typ.
Max.
Unit
0.5
V
Low level voltage
ISINK = 5 mA
0.2
Leakage current
VFAULT = 5 V
1
FAULT
TON
Test conditions
LED current rise time
ILED = 0 to ILED = max
µA
2
Doc ID 16757 Rev 3
ms
9/26
Introduction
6
STCF07
Introduction
The STCF07 is a buck-boost converter designed to power and control the current of a power
white LED. The device operates at a constant switching frequency of 1.8 MHz (typ). It
provides an output voltage from 2.5 V up to 5.3 V, from a 2.7 V to 5.5 V supply voltage. This
supply range allows the device to operate from a single-cell Lithium-Ion battery. The current
is adjustable up to 1 A for an input voltage ranging from 2.7 V to 5.5 V and maximum output
power up to 3.4 W. When the battery voltage is higher than 3.2 V, it is possible to increase
the output power up to 4 W. The device uses an external NTC resistor to sense the
temperature of the white LED. This function may not be needed in all applications, and in
these cases the relevant external components can be omitted.
10/26
Doc ID 16757 Rev 3
STCF07
Logic pin description
7
Logic pin description
7.1
CSEL pin
This input pin allows the setting of two different levels of current. When the voltage on this
pin is low, the internal multiplexer switches the feedback to the FB1 pin, which is the
dedicated feedback pin for low current operation. When the voltage on the CSEL pin is high,
the internal multiplexer switches the feedback to the FB2s pin, and enables the shorting
transistor connected between the FB1 and FB2 pins. The feedback voltage is sensed
directly on the sensing RHC by the connection of FB2s. This sensing pin is dedicated to high
current operation.
7.2
FAULT pin
When the STCF07 is in ON mode (EN is high), the device is able to detect disconnection or
failure of the LED. This information can be used by the system to signal that a problem has
occurred in the LEDs.
7.3
ENABLE pin
This pin functions as an enable input. No internal pull-up or pull-down is provided.
Doc ID 16757 Rev 3
11/26
Detailed description
STCF07
8
Detailed description
8.1
Buck-boost converter
The regulation of the PWM controller is done by sensing the current of the LED through RLC
or RLC + RHC, depending on the CSEL voltage. Depending of the forward voltage of the
flash LED, the device can automatically change between buck (step-down) and boost (stepup) mode:
8.2
–
Boost region = VOUT > VBAT: this configuration is used in most cases, as the
output voltage (VOUT = VF + ILED x RSENSE) is higher than VBAT
–
Buck region = VOUT < VBAT
–
Buck / boost region = VOUT ~ VIN
High current mode
ENABLE = CSEL = VBAT
The STCF07 operates continuously to supply maximum current to the LED up to 800 mA in
high current mode. If high current mode is used in flash applications, then it is possible to
increase the LED current up to 1066 mA.
The current can be adjusted with the RHC resistor. The current is then programmed at:
IHC = 160 mV / RHC
For a current programmed at 800 mA, the sensing resistor is equal to 0.20 Ω.
8.3
Low current mode
ENABLE = VBAT, CSEL = 0
The STCF07 can continuously provide an adjustable current starting from 20 mA in low
current mode. The current adjustment is done with resistor RLC. The current is then
programmed at:
ILC = 160 mV / (RHC + RLC)
The NTC divider for measurement of the LED temperature is active.
8.4
Shutdown mode
ENABLE = 0
When the device is not used, it can be put in shutdown mode, which reduces the quiescent
current to 1 µA. The NTC protection in this mode is not active.
8.5
Soft-start
To avoid spikes on the battery during the startup sequence, a soft-start function has been
implemented. The soft-start function is achieved by progressively increasing the feedback
voltage reference. In worst-case conditions, the startup time, as defined below (IOUT = IMAX),
does not exceed 2 ms.
12/26
Doc ID 16757 Rev 3
STCF07
Figure 4.
Detailed description
Startup: LED current rise time
ENABLE
IOUT
ILED
TON < 2 ms
8.6
STCF07 protection features
8.6.1
Peak current and short-circuit protection
When the peak inductor current exceeds the maximum switch peak current limit of 2.3 A, the
PWM controller turns off and is enabled at the next oscillation period.
8.6.2
Overvoltage protection
The device includes power failure protection, which stops the operation of the PWM
controller when the voltage at the pin VOUT exceeds the OVP threshold. When the voltage
on pin VOUT is reduced by OVHYST, the operation of the controller recovers automatically.
8.6.3
Thermal shutdown protection
Internal thermal shutdown protection switches off the device when the junction temperature
exceeds 140 °C (typ). The hysteresis comparator allows the PWM controller to restart
automatically when the temperature is reduced to 120 °C.
8.6.4
Sensing of LED temperature with the NTC resistor
The device is capable of switching off the power circuit when a high temperature on the LED
is detected. (see Figure 5).
If the sensing LED temperature feature is not used, NTC pin must be left floating and RX pin
must be grounded.
Doc ID 16757 Rev 3
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Detailed description
Figure 5.
STCF07
Typical LED temperature sensing application with the NTC resistor
RNTC = 100 k
NTC
Vref = 1.8 V
VREF = 1.2 V
RX = 15 k
8.6.5
Undervoltage lockout function
If the device is ON and the battery voltage is as low as 2.2 V, the device goes into a FAULT
state and the FAULT pin is put to LOW. To restart the device, the ENABLE pin must be reset
LOW and HIGH.
14/26
Doc ID 16757 Rev 3
STCF07
PCB design
9
PCB design
9.1
PCB design rules
The STCF07 is a powerful switched device, so the PCB must be designed following the
rules for designing switched supplies. It is recommended to use at least a two-layer PCB.
The power wiring must be as short and wide as possible, due to the high current. All external
components should be placed close to the STCF07. High-energy switched loops should be
as small as possible to reduce EMI. Most LEDs require cooling, which may be implemented
by a defined copper area on the PCB. Use the reference guide for each LED to design the
heatsink. Place the RFLASH resistor as close as possible to pins 5 and 6. When a change of
PCB layer is required, the number of vias must be sufficient. Place the NTC resistor as close
as possible to the LED for good temperature sensing. Direct connection of GND and PGND
is needed to achieve accurate output current values. The LED current should not flow
through this track. Sensing of the voltage on the RFLASH resistor must be done by
connecting a wire directly from pin 6 to the RFLASH resistor; no current flows through this
track. Pins 5 and 6 must be connected to the pin of the RFLASH resistor. The exposed pad
must be connected to the PGND, with a track as wide as possible. It is recommended to
place the copper plate, connected through the vias to the exposed pad, on the bottom layer
to create a heatsink for the device. It is further recommended that the copper plate used be
as large as possible to achieve optimal thermal performance.
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15/26
PCB design
STCF07
9.2
PCB design of the demonstration board
Figure 6.
Top layer
Figure 7.
Bottom layer
16/26
Doc ID 16757 Rev 3
STCF07
Figure 8.
PCB design
Top overlay
Doc ID 16757 Rev 3
17/26
PCB design
STCF07
9.3
Schematic of the demonstration board
Figure 9.
Schematic diagram of the STCF07 demonstration board
18/26
Doc ID 16757 Rev 3
STCF07
Typical performance characteristics
Typical performance characteristics
10
Figure 10. IOUT 80 mA vs. VIN
Figure 11. IOUT 800 mA vs. VIN
95.000
950.000
90.000
900.000
Output Current [mA]
1000.000
Output Current [mA]
100.000
85.000
80.000
75.000
70.000
25 °C
65.000
- 40 °C
60.000
800.000
750.000
700.000
25 °C
650.000
- 40 °C
600.000
85°C
55.000
50.000
2.50
850.000
85 °C
550.000
3.00
3.50
4.00
4.50
5.00
5.50
500.000
2.50
3.00
Input Voltage [V]
5.00
5.50
Figure 13. Efficiency vs. VIN, IO = 400 mA
100
100
95
95
90
90
85
85
Efficiency [%]
Efficiency [%]
Figure 12. Efficiency vs. VIN
3.50
4.00
4.50
Input Voltage [V]
80
75
70
80
75
70
65
800 mA
65
60
400 mA
60
-40°C
25°C
85°C
55
55
50
2.5
3
3.5
4
4.5
5
5.5
50
2.5
Input Voltage [V]
3
3.5
4
4.5
5
5.5
Input Voltage [V]
Figure 14. Line transient
Vstep = 600 mVpp, Tr = 10 µs, Tf = 10 µs, VIN = 3.6 V to 4.2 V
Doc ID 16757 Rev 3
19/26
External component selection
STCF07
11
External component selection
11.1
Input and output capacitor selection
For input and output capacitors it is recommended to use ceramic capacitors with low ESR.
For good device stability when supplied by a low input voltage of 2.7 V at maximum ratings,
it is recommended to use 10 µF / 6.3 V as a minimum value for the input capacitor, and 4.7
µF / 6.3 V as a minimum value for the output capacitor.
Note:
See recommended components in Table 5 on page 7.
11.2
Inductor selection
A thick, shielded inductor with low DC series wiring resistance is recommended for this
application. For good efficiency, it is recommended to use an inductor with a series DC
resistance of RDCL < RD / 10, where RD is the dynamic resistance of the LED.
For nominal operation, the peak inductor current can be calculated using the formula:
IPEAK = {(IOUT / η) + [(VOUT - VIN) x VIN²) / (2 x L x F x VOUT²)]} x VOUT / VIN
where:
IPEAK = peak inductor current
IOUT = current sourced at pin VOUT
η = efficiency of the STCF07
VOUT = output voltage at pin VOUT
VIN = input voltage at pin VIN
L = inductance value of the inductor
F = switching frequency
Note:
See recommended components in Table 5 on page 7.
11.3
LED selection
All LEDs with forward voltages from 2.7 V to 5 V are suitable for use with STCF07 device.
The LED forward voltage must include the voltage spread of this value. It is possible to set
the LED current in the two different operating modes (high current mode and low current
mode) through two external sensing resistors.
Note:
See recommended components in Table 5 on page 7.
11.4
RHC selection
The RHC resistor value can be calculated using equations RHC = 160 mV / IHC and PRHC =
RHC * IHC2, where PRHC is the dissipated power on the RHC resistor. It is recommended to
use a 1206 package size thin metal film resistor with 1% or 5% maximum tolerance. The
maximum high LED current for the STCF07 device is 800 mA with a battery voltage range
2.7 V to 5.5 V.
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STCF07
11.5
External component selection
RLC selection
RLC resistor value can be calculated with the following equations:
RLC = (160 mV - ILC * RHC) / ILC and PRLC = RLC * ILC2
where PRLC is the dissipated power on the RLC resistor. It is recommended to use a thin
metal film resistor with a 1% or 5% tolerance.
11.6
NTC and RX resistor selection
The NTC resistor for sensing LED temperature and the RX resistor create a voltage divider.
The output of this divider is compared with the 1.192 V internal voltage reference. When
voltage on the output of the voltage divider is increased over the reference, the logic
switches off the power circuit. Voltage divider is possible to supply from the NTC pin, where
is output of the 1.8 V internal reference.
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Package mechanical data
12
STCF07
Package mechanical data
In order to meet environmental requirements, ST offers these devices in different grades of
ECOPACK® packages, depending on their level of environmental compliance. ECOPACK®
specifications, grade definitions and product status are available at: www.st.com.
ECOPACK® is an ST trademark.
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STCF07
Package mechanical data
QFN16 (4 x 4) mechanical data
mm.
inch.
Dim.
Min.
Typ.
Max.
Min.
Typ.
Max.
0.80
0.90
1.00
31.5
35.4
39.4
A1
0.02
0.05
0.8
2.0
A2
0.65
1.00
25.6
39.4
A3
0.20
A
7.9
b
0.18
0.25
0.30
7.1
9.8
11.8
D
3.85
4.00
4.15
151.6
157.5
163.4
D2
2.10
2.60
82.7
E
3.85
4.15
151.6
E2
2.10
2.60
82.7
e
L
ddd
4.00
0.50
0.30
0.40
102.4
157.5
163.4
102.4
19.7
0.50
0.08
11.8
15.7
19.7
3.1
7653321A
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Package mechanical data
STCF07
Tape & reel QFNxx/DFNxx (4x4) mechanical data
mm.
inch.
Dim.
Min.
Typ.
A
Min.
Typ.
330
C
12.8
D
20.2
N
99
13.2
Max.
12.992
0.504
0.519
0.795
101
T
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Max.
3.898
3.976
14.4
0.567
Ao
4.35
0.171
Bo
4.35
0.171
Ko
1.1
0.043
Po
4
0.157
P
8
0.315
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STCF07
Revision history
13
Revision history
Table 7.
Document revision history
Date
Revision
Changes
18-Nov-2009
1
First release.
12-Apr-2011
2
Updated Table 5 on page 7.
10-Sep-2012
3
Modified: Chapter 8.6.4 on page 13.
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STCF07
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