Data Sheet

TEA1738FT
GreenChip SMPS control IC
Rev. 2 — 14 January 2011
Product data sheet
1. General description
The TEA1738FT is a low cost Switched Mode Power Supply (SMPS) controller IC
intended for flyback topologies. It operates in peak current and frequency control mode.
Frequency jitter has been implemented to reduce ElectroMagnetic Interference (EMI).
Slope compensation is integrated for Continuous Conduction Mode (CCM) operation.
The TEA1738FT IC includes OverPower Protection (OPP). This enables the controller to
operate under overpower situations for a limited amount of time.
Two pins, VINSENSE and PROTECT, are reserved for protection purposes. Input
UnderVoltage Protection (UVP), output OverVoltage Protection (OVP) and
OverTemperature Protection (OTP) can be implemented using a minimal number of
external components.
At low power levels the primary peak current is set to 25 % of the maximum peak current
and the switching frequency is reduced to limit switching losses. The combination of fixed
frequency operation at high output power and frequency reduction at low output power
provides high efficiency over the total load range.
The TEA1738FT enables low cost, highly efficient and reliable supplies for power
requirements up to 75 W to be designed easily and with a minimum number of external
components.
The TEA1738FT is intended to operate in combination with a standby power supply. It has
a lower start-up voltage than the standard TEA1738.
2. Features and benefits
2.1 Features
„
„
„
„
„
„
„
„
„
„
SMPS controller IC enabling low-cost applications
Large input voltage range (12 V to 30 V)
Integrated OverVoltage Protection on pin VCC
Very low supply current during start-up and restart (10 μA typical)
Low start-up voltage (13.2 V typical)
Low supply current during normal operation (0.55 mA typical no load)
Overpower or high/low line compensation
Adjustable overpower time-out
Adjustable overpower restart timer
Fixed switching frequency with frequency jitter to reduce EMI
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
„ Frequency reduction at medium power operation to maintain high efficiency
„ Frequency reduction with fixed minimum peak current at low power operation to
maintain high efficiency at low output power levels
„ Frequency increase at peak power operation
„ Slope compensation for CCM operation
„ Low and adjustable OverCurrent Protection (OCP) trip level
„ Adjustable soft start
„ Two protection inputs (e.g. for input UVP and OTP)
„ IC overtemperature protection
3. Applications
„ All applications requiring efficient and cost-effective power supply solutions up to
75 W.
4. Ordering information
Table 1.
Ordering information
Type number
TEA1738FT
TEA1738FT
Product data sheet
Package
Name
Description
Version
SO8
plastic small outline package; 8 leads; body width 3.9 mm
SOT96-1
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
2 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
5. Block diagram
VCCstart
VCC
13 V
1
11 μA
Q
8
overpower
VCCstop
6V
OPTIMER
2.5 V
driver
clamp
GND
D
400 mV
12 V
22 V
Vctrl(Ipeak)
latch
latch reset
5V
OPP switch
2
COUNT
TO 8
30 V
OVP
TEMPERATURE
PROTECTION
OTP
5.4 V
restart
driver
set
δmax
OPP switch
clamp
RESTART
CONTROL
MODULATION
7 kΩ
frequency reduction
107 μA
OPTIMER
1.2 V / 4.5 V
power down
OSCILLATOR
ANALOG
CONTROL
Vctrl(Ipeak)
7
SLOPE
COMPENSATION
CTRL
VCCstop
overload
DRIVER
3
DRV
Q
set
S
overpower
stop
δmax
Q
R
ISENSE
restart
lowvin
Q
soft start
Vctrl(Ipeak)
OTP
prothigh
protlow
OVP
latch
OCP
S
stop
OVERPOWER
CORRECTION
VINSENSE
latch
Q
R
32
μA
6
protlow
PROTECT
107
μA
VCCstart
power down
lowvin
protlow
R
4
stop
overload
S
LEB
R
0.50 V/0.80 V
restart
soft start
driver
prothigh
BLANK
55
μA
S
lowvin
0.72 V/0.94 V
5
latch reset
VINSENSE
DIGITAL CONTROL
014aab296
Fig 1.
Block diagram
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
3 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
6. Pinning information
6.1 Pinning
VCC
1
GND
2
8
OPTIMER
7
CTRL
TEA1738FT
DRIVER
3
6
PROTECT
ISENSE
4
5
VINSENSE
014aab290
Fig 2.
Pin configuration: TEA1738F (SOT96-1)
6.2 Pin description
Table 2.
TEA1738FT
Product data sheet
Pin description
Symbol
Pin
Description
VCC
1
supply voltage
GND
2
ground
DRIVER
3
gate driver output
ISENSE
4
current sense input
VINSENSE
5
input voltage protection input
PROTECT
6
general purpose protection input
CTRL
7
control input
OPTIMER
8
overpower and restart timer
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
4 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
7. Functional description
7.1 General control
The TEA1738FT contains a flyback circuit controller, a typical configuration of which is
shown in Figure 3.
D3
T1
C7
C1
R1
D1
Z1
C2
O1
R2
VINSENSE
PROTECT
Θ
R4
CTRL
O1
OPTIMER
C4
5
4
6
3
TEA1738FT
7
2
8
1
ISENSE
S1
DRIVER
R10
GND
R6
VCC
C6
C5
R8
R9
VCC
Fig 3.
014aab291
Typical configuration
7.2 Start-up and UnderVoltage LockOut (UVLO)
In a typical application the VCC supply voltage is provided by an additional standby power
supply.
If VCC is lower than Vstartup, the IC current consumption is low (10 μA typical). When VCC
reaches Vstartup the IC first waits for pin VINSENSE to reach the Vstart(VINSENSE) voltage
and for pin PROTECT to reach the Vdet(L)(PROTECT) voltage. When both levels are
reached, the IC charges the ISENSE pin to the Vstart(soft) level and starts switching.
If a protection is triggered the controller stops switching. Depending on the protection
triggered it either causes a restart or latches the converter to an off-state.
A restart caused by a protection rapidly charges the OPTIMER pin to 4.5 V (typical). The
TEA1738FT enters Power-down mode until the OPTIMER pin discharges down to
1.2 V (typical). In Power-down mode, the IC consumes a very low supply current
(10 μA typical) and the VCC pin is clamped at 22 V (typical) by an internal clamp circuit.
When the voltage on pin OPTIMER drops below 1.2 V (typical) and the VCC pin voltage is
above the VCC start-up voltage (see Figure 4), the IC restarts.
When a latched protection is triggered, the TEA1738FT immediately enters Power-down
mode. The VCC pin is clamped to a voltage just above the latch protection reset voltage
(Vrst(latch) + 1 V).
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
5 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
Vstartup
Vth(UVLO)
VCC
soft start
soft start
ISENSE
Vstart(VINSENSE)
Vdet(L)(VINSENSE)
Vdet(H)(PROTECT)
VINSENSE
Vdet(L)(PROTECT)
PROTECT
4.5 V
1.2 V
OPTIMER
VO
(power-down)
charging VCC
capacitor
starting
converter
normal
operation
protection
restart
014aab292
Fig 4.
Start-up sequence, normal operation and restart sequence
When the voltage on pin VCC drops below the Vth(UVLO) level during normal operation, the
controller stops switching and enters the Restart mode. In Restart mode the driver output
is disabled.
7.3 Supply management
All internal reference voltages are derived from a temperature compensated on-chip band
gap circuit. Internal reference currents are derived from a trimmed and temperature
compensated current reference circuit.
7.4 OverVoltage Protection (VCC pin)
An OVP circuit is connected to the VCC pin. After 8 consecutive OVP cycles the IC
triggers the latched protection. When VCC drops below the Vth(OVP) voltage before
count=8 is reached, the counter is reset to zero.
If a lower overvoltage protection level is needed, a Zener diode can be connected
between the VCC pin and the PROTECT pin.
7.5 Input voltage detection (VINSENSE pin)
In a typical application the mains input voltage can be detected by the VINSENSE pin.
Switching does not take place until the voltage on VINSENSE has reached the
Vstart(VINSENSE) voltage (0.94 V typical).
When during operation the VINSENSE voltage drops below Vdet(L)(VINSENSE)
(0.72 V typical), the converter stops switching and performs a restart.
An internal clamp of 5.2 V (typical) protects this pin from excessive voltages.
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
6 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
7.6 Protection input (PROTECT PIN)
Pin PROTECT is a general purpose input pin, which can be used to switch off the
converter (latched protection). The converter is stopped when the voltage on this pin is
pulled above Vdet(H)(PROTECT) (0.8 V typical) or below Vdet(L)(PROTECT) (0.5 V typical). A
current of 32 μA (typical) flows out of the chip when the pin voltage is at the
Vdet(L)(PROTECT) level. A current of 107 μA (typical) flows into the chip when the pin voltage
is at the Vdet(H)(PROTECT) level.
The PROTECT input can be used to create an overvoltage detection and OTP functions.
A small capacitor can be connected to the pin if the protections on this pin are not used.
An internal clamp of 4.1 V (typical) protects this pin from excessive voltages.
7.7 Duty cycle control (CTRL pin)
The output power of the converter is regulated by the CTRL pin. This pin is connected to
an internal 5.4 V supply using an internal 7 kΩ resistor.
The CTRL pin voltage sets the peak current which is measured via pin ISENSE.
(see Section 7.11) At low and medium output power the switching frequency is reduced
(see Section 7.13). The maximum duty cycle is limited to 80 % (typical).
7.8 Slope compensation (CTRL pin)
A slope compensation circuit is integrated in the IC for CCM. Slope compensation
guarantees stable operation for duty cycles greater than 50 %.
7.9 Overpower timer (OPTIMER pin)
If the OPTIMER pin is connected to capacitor C4 (see Figure 3), a temporary overload
situation is allowed. Vctrl(Ipeak) (see Figure 1) is set by pin CTRL. When Vctrl(Ipeak) is above
400 mV, the IIO(OPTIMER) current (11 μA typical) is sourced from the OPTIMER pin. If the
voltage on the OPTIMER pin reaches the Vprot(OPTIMER) voltage (2.5 V typical) the
OverPower Protection (OPP) is triggered (see Figure 5).
When the Vprot(OPTIMER) voltage is reached, the TEA1738FT restarts.
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
7 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
IO
VO
400 mV
VISENSE
Vprot(OPTIMER)
VOPTIMER
normal
load
high load
high load
protection
014aaa930
Fig 5.
Overpower delay (TEA1738FT)
7.10 Current mode control (ISENSE pin)
Current mode control is used for its good line regulation.
The primary current is sensed by the ISENSE pin across an external resistor R9
(see Figure 3) and compared with an internal control voltage. The internal control voltage
is proportional to the CTRL pin voltage (see Figure 6).
014aab293
0.6
frequency
increase
Vsense(max)
(V)
frequency
reduction
0.4
frequency
reduction
0.2
0
0
1
2
3
4
VCTRL (V)
Fig 6.
Peak current control
Leading edge blanking prevents false triggering due to capacitive discharge when
switching on the external power switch (see Figure 7).
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
8 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
tleb
Vsense(max)
VISENSE
t
014aaa932
Fig 7.
Leading edge blanking
7.11 Overpower or high/low line compensation
(VINSENSE and ISENSE pins)
The overpower compensation function can be used to realize a maximum output power
which is nearly constant over the full input mains.
The overpower compensation circuit measures the input voltage on the VINSENSE pin
and outputs a proportionally dependent current on the ISENSE pin. The DC voltage
across the soft start resistor limits the maximum peak current on the current sense resistor
(see Figure 8).
At low output power levels the overpower compensation circuit is switched off.
2
1.7
IISENSE
(μA)
0.68
1
2
3
VVINSENSE (V)
4
014aaa933
Fig 8.
Overpower compensation
7.12 Soft start-up (ISENSE pin)
A soft start is performed to prevent audible noise during start-up or a restart condition.
Before the converter (re)starts, the soft start capacitor C6 (see Figure 3) on the ISENSE
pin is charged. When the converter (re)starts switching, the primary peak current slowly
increases as the soft start capacitor discharges through the soft start resistor (R6, see
Figure 3).
The soft start time constant is set by the soft start capacitor value chosen. The soft start
resistor value must also be taken into account, but this value is typically defined by the
overpower compensation (see Section 7.11).
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
9 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
7.13 Peak power, medium power and low power operation
The switching frequency is increased for peak power operation. In medium power
operation the switching losses are reduced by lowering the switching frequency. A second
frequency reduction step is made when the output power is reduced to low power. In low
power operation the converter switching frequency is reduced while the peak current is
set to 25 % of the maximum peak current. (see Figure 6 and Figure 9)
fosc
peak power
80 kHz
high
power
66 kHz
medium
power
low power
28 kHz
2
1
3
VCTRL
Fig 9.
014aab294
Frequency control
7.14 Driver (pin DRIVER)
The driver circuit to the gate of the power MOSFET has a current sourcing capability of
typically 300 mA and a current sink capability of typically 750 mA. This allows for a fast
turn-on and turn-off of the power MOSFET for efficient operation.
7.15 OverTemperature Protection (OTP)
Integrated temperature protection ensures the IC stops switching if the junction
temperature exceeds the thermal shutdown temperature limit.
OTP is a latched protection. It can be reset by removing the voltage on pin VCC.
8. Limiting values
Table 3.
Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
Symbol
Parameter
Conditions
Min
Max
Unit
VCC
supply voltage
continuous
−0.4
+30
V
t < 100 ms
-
35
V
VVINSENSE
voltage on pin VINSENSE
current limited
−0.4
+5.5
V
VPROTECT
voltage on pin PROTECT
current limited
−0.4
+5
V
VCTRL
voltage on pin CTRL
−0.4
+5.5
V
VIO(OPTIMER)
input/output voltage on pin
OPTIMER
−0.4
+5
V
Voltages
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
10 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
Table 3.
Limiting values …continued
In accordance with the Absolute Maximum Rating System (IEC 60134).
Symbol
Parameter
Conditions
Min
Max
Unit
VISENSE
voltage on pin ISENSE
current limited
−0.4
+5
V
δ < 10 %
Currents
ICC
supply current
-
+0.4
A
II(VINSENSE)
input current on pin
VINSENSE
−1
+1
mA
II(PROTECT)
input current on pin
PROTECT
−1
+1
mA
ICTRL
current on pin CTRL
−3
0
mA
IISENSE
current on pin ISENSE
−10
+1
mA
IDRIVER
current on pin DRIVER
δ < 10 %
−0.4
+1
A
Ptot
total power dissipation
Tamb < 75 °C
-
0.5
W
Tstg
storage temperature
−55
+150
°C
Tj
junction temperature
−40
+150
°C
General
ElectroStatic Discharge (ESD)
VESD
electrostatic discharge
voltage
class 1
human body
model
[1]
-
4000
V
machine model
[2]
-
300
V
-
750
V
charged device
model
[1]
Equivalent to discharging a 100 pF capacitor through a 1.5 kΩ series resistor.
[2]
Equivalent to discharging a 200 pF capacitor through a 0.75 μH coil and a 10 Ω resistor.
9. Thermal characteristics
Table 4.
TEA1738FT
Product data sheet
Thermal characteristics
Symbol
Parameter
Conditions
Typ
Unit
Rth(j-a)
thermal resistance from
junction to ambient
in free air;
JEDEC test board
150
K/W
Rth(j-c)
thermal resistance from
junction to case
in free air;
JEDEC test board
79
K/W
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
11 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
10. Characteristics
Table 5.
Characteristics
Tamb = 25 °C; VCC = 20 V; all voltages are measured with respect to ground (pin 2); currents are positive when flowing into
the IC; unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
Supply voltage management (pin VCC)
Vstartup
start-up voltage
-
13.2
14.2
V
Vth(UVLO)
undervoltage lockout
threshold voltage
11.2
12.2
13.2
V
Vth(ovp)
overvoltage
protection threshold
voltage
29
30
31
V
Ncy(ovp)
number of
overvoltage
protection cycles
7
-
8
Vclamp(VCC)
clamp voltage on pin
VCC
activated during restart;
ICC = 100 μA
-
Vstartup + 1
-
V
activated during latched
protection; ICC = 100 μA
-
Vrst(latch) + 1 -
V
activated during latched
protection; ICC = 500 μA
-
-
Vrst(latch) + 4
V
Iclamp(VCC)
clamp current on pin
VCC
activated during restart;
VCC = 25 V
730
-
-
μA
Vhys
hysteresis voltage
Vstartup − Vth(UVLO)
50
-
-
mV
ICC(startup)
start-up supply
current
VCC < Vstartup
5
10
15
μA
ICC(oper)
operating supply
current
no load on pin DRIVER;
δ=2%
-
0.55
-
mA
no load on pin DRIVER;
δ = 25 %
-
0.59
-
mA
4
5
6
V
0.89
0.94
0.99
V
Vrst(latch)
latched reset voltage
Input voltage sensing (pin VINSENSE)
Vstart(VINSENSE)
start voltage on pin
VINSENSE
detection level
Vdet(L)(VINSENSE)
LOW-level detection
voltage on pin
VINSENSE
0.68
0.72
0.76
V
IO(VINSENSE)
output current on pin
VINSENSE
-
−9
-
nA
Vclamp(VINSENSE)
clamp voltage on pin
VINSENSE
-
5.2
-
V
II(VINSENSE) = 50 μA
Protection input (pin PROTECT)
Vdet(L)(PROTECT)
LOW-level detection
voltage on pin
PROTECT
0.47
0.50
0.53
V
Vdet(H)(PROTECT)
HIGH-level detection
voltage on pin
PROTECT
0.75
0.8
0.85
V
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
12 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
Table 5.
Characteristics …continued
Tamb = 25 °C; VCC = 20 V; all voltages are measured with respect to ground (pin 2); currents are positive when flowing into
the IC; unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
IO(PROTECT)
output current on pin
PROTECT
VPROTECT = Vlow(PROTECT)
−34
−32
−30
μA
87
107
127
μA
Vclamp(PROTECT)
clamp voltage on pin
PROTECT
3.5
4.1
4.7
V
for minimum flyback peak
current
1.5
1.8
2.1
V
for maximum flyback
peak current
3.4
3.9
4.3
V
5
7
9
kΩ
VCTRL = 1.4 V
−0.7
−0.5
−0.3
mA
VCTRL = 3.7 V
−0.28
−0.2
−0.12
mA
peak power
-
78
-
kHz
high power
-
63
-
kHz
medium power
-
26.5
-
kHz
VPROTECT = Vhigh(PROTECT)
II(PROTECT) = 200 μA
[1]
Peak current control (pin CTRL)
VCTRL
voltage on pin CTRL
Rint(CTRL)
internal resistance on
pin CTRL
IO(CTRL)
output current on pin
CTRL
Pulse width modulator
fosc
oscillator frequency
fmod
modulation frequency
210
280
350
Hz
Δfmod
modulation frequency high power
variation
±3
±4
±5
kHz
δmax
maximum duty cycle
-
80
-
%
Vstart(red)f
frequency reduction
start voltage
pin CTRL transfer
between high and
medium power
-
2.7
-
V
going to low power
1.5
1.8
2.1
V
pin CTRL
1.25
1.55
1.85
V
2.4
2.5
2.6
V
no overpower situation
100
150
200
μA
overpower situation
−12.2
−10.7
−9.2
μA
restart voltage on pin
OPTIMER
low level
0.8
1.2
1.6
V
high level
4.1
4.5
4.9
V
restart current on pin
OPTIMER
charging OPTIMER
capacitor
−127
−107
−87
μA
discharging OPTIMER
capacitor
−0.1
0
0.1
μA
Vδ(zero)
zero duty cycle
voltage
Overpower protection (pin OPTIMER)
Vprot(OPTIMER)
protection voltage on
pin OPTIMER
Iprot(OPTIMER)
protection current on
pin OPTIMER
Restart timer (pin OPTIMER)
Vrestart(OPTIMER)
Irestart(OPTIMER)
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
13 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
Table 5.
Characteristics …continued
Tamb = 25 °C; VCC = 20 V; all voltages are measured with respect to ground (pin 2); currents are positive when flowing into
the IC; unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
ΔV/Δt = 50 mV/μs;
VVINSENSE = 0.78 V
0.48
0.51
0.54
V
ΔV/Δt = 200 mV/μs;
VVINSENSE = 0.78 V
0.50
0.53
0.56
V
370
400
430
mV
-
19
-
mV/μs
250
300
350
ns
-
0.28
-
μA
-
1.7
-
μA
−63
−55
−47
μA
-
Vsense(max)
-
V
12
-
-
kΩ
Current sense (pin ISENSE)
Vsense(max)
maximum sense
voltage
Vth(sense)opp
overpower protection
sense threshold
voltage
ΔVISENSE/Δt
slope compensation
voltage on pin
ISENSE
tleb
leading edge blanking
time
ΔV/Δt = 50 mV/μs, high
power mode
Overpower compensation (pin VINSENSE and pin ISENSE)
Iopc(ISENSE)
overpower
VVINSENSE = 1 V;
compensation current Vsense(max) > 400 mV
on pin ISENSE
VVINSENSE = 3 V;
Vsense(max) > 400 mV
Soft start (pin ISENSE)
Istart(soft)
soft start current
Vstart(soft)
soft start voltage
Rstart(soft)
soft start resistance
VCTRL = 4 V;
enable voltage
Driver (pin DRIVER)
Isource(DRIVER)
source current on pin VDRIVER = 2 V
DRIVER
-
−0.3
−0.25
A
Isink(DRIVER)
sink current on pin
DRIVER
VDRIVER = 2 V
0.25
0.3
-
A
VDRIVER = 10 V
0.6
0.75
-
A
9
10.5
12
V
130
140
150
°C
VO(DRIVER)max
maximum output
voltage on pin
DRIVER
Temperature protection
Tpl(IC)
[1]
IC protection level
temperature
The clamp voltage on the PROTECT pin is lowered when the IC is in Power-down mode (latched or restart protection).
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
14 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
11. Application information
A power supply with the TEA1738FT is a flyback converter operating in Continuous
conduction mode. See Figure 10.
Capacitor C5 buffers the IC supply voltage, which is powered by an additional standby
power supply. Sense resistor R9 converts the current through MOSFET S1 into a voltage
on pin ISENSE. The values of resistor R9 defines the maximum primary peak current in
MOSFET S1.
In the example shown in Figure 10 the PROTECT pin is used for OTP. The OTP level is
set by Negative Temperature Coefficient (NTC) resistor R4. If an (additional) external OVP
is required, a Zener diode can be connected between the VCC pin and the PROTECT pin.
The VINSENSE pin is used for mains voltage detection and resistors R1 and R2 set the
start voltage to about 80 V (AC).
The overpower protection time, defined by capacitor C4, is set to 60 ms.
The restart time is defined by capacitor C4 and resistor R8 at 0.5 s.
Resistor R6 and capacitor C6 define the soft start time. Resistor R5 prevents the soft start
capacitor C6 from being charged during normal operation due to negative voltage spikes
across the current sense resistor R9.
Capacitor C3 is added to reduce the noise on the CTRL pin.
Resistor R10 is required to limit the current spikes to the DRIVER pin due to parasitic
inductance of the current sense resistor R9.
T1
C1
68 μF
D1
C7
R1
10 MΩ
C2
Z1
100 nF
O1
R2
82 kΩ
VINSENSE
PROTECT
R4
Θ 200 kΩ
CTRL
OPTIMER
O1
5
4
6
3
TEA1738FT
7
2
8
1
ISENSE
DRIVER
R5
470 Ω
10 Ω
R6
GND
22 kΩ
C6
VCC
C3
1 nF
C4
220 nF
C5
100 nF
R8
2.2 MΩ
S1
R10
220 nF
R9
0.25 Ω
VCC
014aab295
Fig 10. Typical application
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
15 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
12. Package outline
SO8: plastic small outline package; 8 leads; body width 3.9 mm
SOT96-1
D
E
A
X
c
y
HE
v M A
Z
5
8
Q
A2
A
(A 3)
A1
pin 1 index
θ
Lp
L
4
1
e
detail X
w M
bp
0
2.5
5 mm
scale
DIMENSIONS (inch dimensions are derived from the original mm dimensions)
UNIT
A
max.
A1
A2
A3
bp
c
D (1)
E (2)
e
HE
L
Lp
Q
v
w
y
Z (1)
mm
1.75
0.25
0.10
1.45
1.25
0.25
0.49
0.36
0.25
0.19
5.0
4.8
4.0
3.8
1.27
6.2
5.8
1.05
1.0
0.4
0.7
0.6
0.25
0.25
0.1
0.7
0.3
0.069
0.010 0.057
0.004 0.049
0.01
0.019 0.0100
0.014 0.0075
0.20
0.19
0.16
0.15
0.05
0.01
0.01
0.004
0.028
0.012
inches
0.244
0.039 0.028
0.041
0.228
0.016 0.024
θ
o
8
o
0
Notes
1. Plastic or metal protrusions of 0.15 mm (0.006 inch) maximum per side are not included.
2. Plastic or metal protrusions of 0.25 mm (0.01 inch) maximum per side are not included.
REFERENCES
OUTLINE
VERSION
IEC
JEDEC
SOT96-1
076E03
MS-012
JEITA
EUROPEAN
PROJECTION
ISSUE DATE
99-12-27
03-02-18
Fig 11. Package outline SOT96-1 (SO8)
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
16 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
13. Revision history
Table 6.
Revision history
Document ID
Release date
Data sheet status
Change notice
Supersedes
TEA1738FT v.2
20110114
Product data sheet
-
TEA1738FT v.1
TEA1738FT v.1
20101230
Preliminary data sheet
-
-
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
17 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
14. Legal information
14.1 Data sheet status
Document status[1][2]
Product status[3]
Definition
Objective [short] data sheet
Development
This document contains data from the objective specification for product development.
Preliminary [short] data sheet
Qualification
This document contains data from the preliminary specification.
Product [short] data sheet
Production
This document contains the product specification.
[1]
Please consult the most recently issued document before initiating or completing a design.
[2]
The term ‘short data sheet’ is explained in section “Definitions”.
[3]
The product status of device(s) described in this document may have changed since this document was published and may differ in case of multiple devices. The latest product status
information is available on the Internet at URL http://www.nxp.com.
14.2 Definitions
Draft — The document is a draft version only. The content is still under
internal review and subject to formal approval, which may result in
modifications or additions. NXP Semiconductors does not give any
representations or warranties as to the accuracy or completeness of
information included herein and shall have no liability for the consequences of
use of such information.
Short data sheet — A short data sheet is an extract from a full data sheet
with the same product type number(s) and title. A short data sheet is intended
for quick reference only and should not be relied upon to contain detailed and
full information. For detailed and full information see the relevant full data
sheet, which is available on request via the local NXP Semiconductors sales
office. In case of any inconsistency or conflict with the short data sheet, the
full data sheet shall prevail.
Product specification — The information and data provided in a Product
data sheet shall define the specification of the product as agreed between
NXP Semiconductors and its customer, unless NXP Semiconductors and
customer have explicitly agreed otherwise in writing. In no event however,
shall an agreement be valid in which the NXP Semiconductors product is
deemed to offer functions and qualities beyond those described in the
Product data sheet.
14.3 Disclaimers
Limited warranty and liability — Information in this document is believed to
be accurate and reliable. However, NXP Semiconductors does not give any
representations or warranties, expressed or implied, as to the accuracy or
completeness of such information and shall have no liability for the
consequences of use of such information.
In no event shall NXP Semiconductors be liable for any indirect, incidental,
punitive, special or consequential damages (including - without limitation - lost
profits, lost savings, business interruption, costs related to the removal or
replacement of any products or rework charges) whether or not such
damages are based on tort (including negligence), warranty, breach of
contract or any other legal theory.
Notwithstanding any damages that customer might incur for any reason
whatsoever, NXP Semiconductors’ aggregate and cumulative liability towards
customer for the products described herein shall be limited in accordance
with the Terms and conditions of commercial sale of NXP Semiconductors.
malfunction of an NXP Semiconductors product can reasonably be expected
to result in personal injury, death or severe property or environmental
damage. NXP Semiconductors accepts no liability for inclusion and/or use of
NXP Semiconductors products in such equipment or applications and
therefore such inclusion and/or use is at the customer’s own risk.
Applications — Applications that are described herein for any of these
products are for illustrative purposes only. NXP Semiconductors makes no
representation or warranty that such applications will be suitable for the
specified use without further testing or modification.
Customers are responsible for the design and operation of their applications
and products using NXP Semiconductors products, and NXP Semiconductors
accepts no liability for any assistance with applications or customer product
design. It is customer’s sole responsibility to determine whether the NXP
Semiconductors product is suitable and fit for the customer’s applications and
products planned, as well as for the planned application and use of
customer’s third party customer(s). Customers should provide appropriate
design and operating safeguards to minimize the risks associated with their
applications and products.
NXP Semiconductors does not accept any liability related to any default,
damage, costs or problem which is based on any weakness or default in the
customer’s applications or products, or the application or use by customer’s
third party customer(s). Customer is responsible for doing all necessary
testing for the customer’s applications and products using NXP
Semiconductors products in order to avoid a default of the applications and
the products or of the application or use by customer’s third party
customer(s). NXP does not accept any liability in this respect.
Limiting values — Stress above one or more limiting values (as defined in
the Absolute Maximum Ratings System of IEC 60134) will cause permanent
damage to the device. Limiting values are stress ratings only and (proper)
operation of the device at these or any other conditions above those given in
the Recommended operating conditions section (if present) or the
Characteristics sections of this document is not warranted. Constant or
repeated exposure to limiting values will permanently and irreversibly affect
the quality and reliability of the device.
Terms and conditions of commercial sale — NXP Semiconductors
products are sold subject to the general terms and conditions of commercial
sale, as published at http://www.nxp.com/profile/terms, unless otherwise
agreed in a valid written individual agreement. In case an individual
agreement is concluded only the terms and conditions of the respective
agreement shall apply. NXP Semiconductors hereby expressly objects to
applying the customer’s general terms and conditions with regard to the
purchase of NXP Semiconductors products by customer.
Right to make changes — NXP Semiconductors reserves the right to make
changes to information published in this document, including without
limitation specifications and product descriptions, at any time and without
notice. This document supersedes and replaces all information supplied prior
to the publication hereof.
No offer to sell or license — Nothing in this document may be interpreted or
construed as an offer to sell products that is open for acceptance or the grant,
conveyance or implication of any license under any copyrights, patents or
other industrial or intellectual property rights.
Suitability for use — NXP Semiconductors products are not designed,
authorized or warranted to be suitable for use in life support, life-critical or
safety-critical systems or equipment, nor in applications where failure or
Export control — This document as well as the item(s) described herein
may be subject to export control regulations. Export might require a prior
authorization from national authorities.
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
18 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
Non-automotive qualified products — Unless this data sheet expressly
states that this specific NXP Semiconductors product is automotive qualified,
the product is not suitable for automotive use. It is neither qualified nor tested
in accordance with automotive testing or application requirements. NXP
Semiconductors accepts no liability for inclusion and/or use of
non-automotive qualified products in automotive equipment or applications.
In the event that customer uses the product for design-in and use in
automotive applications to automotive specifications and standards, customer
(a) shall use the product without NXP Semiconductors’ warranty of the
product for such automotive applications, use and specifications, and (b)
whenever customer uses the product for automotive applications beyond
NXP Semiconductors’ specifications such use shall be solely at customer’s
own risk, and (c) customer fully indemnifies NXP Semiconductors for any
liability, damages or failed product claims resulting from customer design and
use of the product for automotive applications beyond NXP Semiconductors’
standard warranty and NXP Semiconductors’ product specifications.
14.4 Trademarks
Notice: All referenced brands, product names, service names and trademarks
are the property of their respective owners.
GreenChip — is a trademark of NXP B.V.
15. Contact information
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: [email protected]
TEA1738FT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 January 2011
© NXP B.V. 2011. All rights reserved.
19 of 20
TEA1738FT
NXP Semiconductors
GreenChip SMPS control IC
16. Contents
1
2
2.1
3
4
5
6
6.1
6.2
7
7.1
7.2
7.3
7.4
7.5
7.6
7.7
7.8
7.9
7.10
7.11
7.12
7.13
7.14
7.15
8
9
10
11
12
13
14
14.1
14.2
14.3
14.4
15
16
General description . . . . . . . . . . . . . . . . . . . . . . 1
Features and benefits . . . . . . . . . . . . . . . . . . . . 1
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Ordering information . . . . . . . . . . . . . . . . . . . . . 2
Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pinning information . . . . . . . . . . . . . . . . . . . . . . 4
Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 4
Functional description . . . . . . . . . . . . . . . . . . . 5
General control . . . . . . . . . . . . . . . . . . . . . . . . . 5
Start-up and UnderVoltage LockOut (UVLO) . . 5
Supply management. . . . . . . . . . . . . . . . . . . . . 6
OverVoltage Protection (VCC pin) . . . . . . . . . . 6
Input voltage detection (VINSENSE pin) . . . . . 6
Protection input (PROTECT PIN) . . . . . . . . . . . 7
Duty cycle control (CTRL pin). . . . . . . . . . . . . . 7
Slope compensation (CTRL pin). . . . . . . . . . . . 7
Overpower timer (OPTIMER pin) . . . . . . . . . . . 7
Current mode control (ISENSE pin) . . . . . . . . . 8
Overpower or high/low line compensation
(VINSENSE and ISENSE pins) . . . . . . . . . . . . 9
Soft start-up (ISENSE pin) . . . . . . . . . . . . . . . . 9
Peak power, medium power and low power
operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Driver (pin DRIVER) . . . . . . . . . . . . . . . . . . . . 10
OverTemperature Protection (OTP) . . . . . . . . 10
Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . 10
Thermal characteristics . . . . . . . . . . . . . . . . . 11
Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . 12
Application information. . . . . . . . . . . . . . . . . . 15
Package outline . . . . . . . . . . . . . . . . . . . . . . . . 16
Revision history . . . . . . . . . . . . . . . . . . . . . . . . 17
Legal information. . . . . . . . . . . . . . . . . . . . . . . 18
Data sheet status . . . . . . . . . . . . . . . . . . . . . . 18
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Trademarks. . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Contact information. . . . . . . . . . . . . . . . . . . . . 19
Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Please be aware that important notices concerning this document and the product(s)
described herein, have been included in section ‘Legal information’.
© NXP B.V. 2011.
All rights reserved.
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: [email protected]
Date of release: 14 January 2011
Document identifier: TEA1738FT
Similar pages