TEA1738T; TEA1738LT GreenChip SMPS control IC Rev. 1 — 31 December 2010 Preliminary data sheet 1. General description The TEA1738(L) is a low cost Switched Mode Power Supply (SMPS) controller IC intended for flyback topologies. The TEA1738(L) 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 TEA1738(L) 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 TEA1738(L) 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. 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 (OVP) on pin VCC Very low supply current during start-up and restart (10 A typical) Low supply current during normal operation (0.55 mA typical without load) Overpower or high/low line compensation Adjustable overpower time-out Adjustable overpower restart timer Fixed switching frequency with frequency jitter to reduce EMI Frequency reduction at medium power operation to maintain high efficiency TEA1738T; TEA1738LT NXP Semiconductors GreenChip SMPS control IC Frequency reduction with fixed minimum peak current at low power 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 Package Name Description Version TEA1738T SO8 plastic small outline package; 8 leads; body width 3.9 mm SOT96-1 TEA1738LT SO8 plastic small outline package; 8 leads; body width 3.9 mm SOT96-1 TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 2 of 21 TEA1738T; TEA1738LT NXP Semiconductors GreenChip SMPS control IC 5. Block diagram VCCstart VCC 21 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 COUNT TO 8 δ max prot restart BLANK 55 μA ISENSE soft start S restart LEB Q R 4 soft start Vctrl(Ipeak) latch OCP S stop OVERPOWER CORRECTION VINSENSE latch Q R S driver R stop δ max δ max prot overload(1) lowvin VCCstart power down lowvin protlow OTP prothigh protlow OVP overload(1) prothigh 32 μA 0.50 V/0.80 V protlow lowvin 6 PROTECT 107 μA 0.72 V/0.94 V 5 latch reset DIGITAL CONTROL VINSENSE 001aan167 (1) In the TEA1738LT the overload signal switches the IC to the latched-off state. In the TEA1738T the overload signal triggers the restart timer. Fig 1. Block diagram TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 3 of 21 TEA1738T; TEA1738LT NXP Semiconductors GreenChip SMPS control IC 6. Pinning information 6.1 Pinning VCC 1 GND 2 DRIVER 3 ISENSE 4 8 OPTIMER TEA1738T 7 CTRL TEA1738LT 6 PROTECT 5 VINSENSE 001aan168 Fig 2. Pin configuration: TEA1738(L) (SOT96-1) 6.2 Pin description Table 2. TEA1738T_TEA1738LT Preliminary 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. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 4 of 21 TEA1738T; TEA1738LT NXP Semiconductors GreenChip SMPS control IC 7. Functional description 7.1 General control The TEA1738(L) contains a flyback circuit controller, a typical configuration of which is shown in Figure 3. T1 C1 D1 R1 D3 C2 C7 R2 VINSENSE PROTECT R3 Θ 4 6 3 ISENSE S1 DRIVER TEA1738T CTRL GND 7 TEA1738LT 2 R4 O1 5 OPTIMER C4 R8 8 1 R10 Z1 O1 R6 VCC C6 C5 R9 D2 001aan169 Fig 3. Typical configuration 7.2 Start-up and UnderVoltage LockOut (UVLO) Initially, the capacitor on the VCC pin is charged from the high voltage mains via resistor R3. If VCC is lower than Vstartup, the IC current consumption is low (10 A 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. In a typical application the supply voltage is taken over by the auxiliary winding of the transformer. 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 TEA1738(L) 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 A 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 TEA1738(L) immediately enters Power-down mode. The VCC pin is clamped to a voltage just above the latch protection reset voltage (Vrst(latch) + 1 V). TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 5 of 21 TEA1738T; TEA1738LT 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 001aan170 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 the TEA1738T enters Restart mode. In Restart mode the driver output is disabled and the VCC pin voltage is recharged via resistor R3 to the rectified mains voltage. For the TEA1738LT a VCC undervoltage, which does not occur during a start-up event, latches the IC in an off-state. 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. TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 6 of 21 TEA1738T; TEA1738LT 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 A (typical) flows out of the chip when the pin voltage is at the Vdet(L)(PROTECT) level. A current of 107 A (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 k 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). After 8 consecutive converter strokes at maximum duty cycle the restart protection is activated. Typically this occurs when the mains input voltage is removed. 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 A 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). TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 7 of 21 TEA1738T; TEA1738LT NXP Semiconductors GreenChip SMPS control IC IO VO 400 mV VISENSE Vprot(OPTIMER) VOPTIMER high load normal load high load protection 014aaa930 Fig 5. Overpower delay (TEA1738T) In the TEA1738T when the Vprot(OPTIMER) voltage is reached the device is restarted. The TEA1738LT is latched in an off state when the Vprot(OPTIMER) voltage is reached. IO VO 400 mV VISENSE Vprot(OPTIMER) VOPTIMER high load normal load high load protection 014aaa968 Fig 6. Overpower delay: latched (TEA1738LT) 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 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 7). TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 8 of 21 TEA1738T; TEA1738LT NXP Semiconductors GreenChip SMPS control IC 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 7. Peak current control Leading edge blanking prevents false triggering due to capacitive discharge when switching on the external power switch (see Figure 8). tleb Vsense(max) VISENSE t 014aaa932 Fig 8. 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 9). At low output power levels the overpower compensation circuit is switched off. TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 9 of 21 TEA1738T; TEA1738LT NXP Semiconductors GreenChip SMPS control IC 2 1.7 IISENSE (μA) 0.68 1 2 3 VVINSENSE (V) 4 014aaa933 Fig 9. 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, 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). 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 7 and Figure 10). fosc peak power 80 kHz high power 66 kHz medium power low power 28 kHz 1 2 3 VCTRL 014aab294 Fig 10. Frequency control TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 10 of 21 TEA1738T; TEA1738LT NXP Semiconductors GreenChip SMPS control IC 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 supply voltage continuous 0.4 +30 V t < 100 ms - 35 V Voltages VCC 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 VISENSE voltage on pin ISENSE current limited 0.4 +5 V ICC supply current < 10 % - 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 < 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 Currents General TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 11 of 21 TEA1738T; TEA1738LT NXP Semiconductors GreenChip SMPS control IC Table 3. Limiting values …continued In accordance with the Absolute Maximum Rating System (IEC 60134). Symbol Parameter Conditions electrostatic discharge voltage class 1 Min Max Unit ESD VESD 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 k series resistor. [2] Equivalent to discharging a 200 pF capacitor through a 0.75 H coil and a 10 resistor. 9. Thermal characteristics Table 4. 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 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 18.6 20.6 22.6 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 A - Vstartup + 1 - V activated during latched protection; ICC = 100 A - Vrst(latch) + 1 - V activated during latched protection; ICC = 500 A - - Vrst(latch) + 4 V Iclamp(VCC) clamp current on pin VCC activated during restart; VCC = 25 V 730 - - A Vhys hysteresis voltage Vstartup Vth(UVLO) 7.5 9 10.5 V ICC(startup) start-up supply current VCC < Vstartup 5 10 15 A TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 12 of 21 TEA1738T; TEA1738LT 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 ICC(oper) operating supply current no load on pin DRIVER; =2% - 0.55 - mA no load on pin DRIVER; = 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 A 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 IO(PROTECT) output current on pin PROTECT VPROTECT = Vlow(PROTECT) 34 32 30 A VPROTECT = Vhigh(PROTECT 87 107 127 A 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 k 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 210 280 350 Hz 3 4 5 kHz - 80 - ) Vclamp(PROTECT) clamp voltage on pin PROTECT II(PROTECT) = 200 A [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 fmod modulation frequency variation max maximum duty cycle TEA1738T_TEA1738LT Preliminary data sheet high power All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 13 of 21 TEA1738T; TEA1738LT 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 Ncy(sw)max Number of switching cycles with maximum duty cycle Vstart(red)f frequency reduction start voltage V(zero) Conditions Min Typ Max 7 - 8 pin CTRL transfer between high and medium power - 2.7 - V pin CTRL going to low power 1.5 1.8 2.1 V 1.25 1.55 1.85 V 2.4 2.5 2.6 V no overpower situation 100 150 200 A overpower situation 12.2 10.7 9.2 A 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 A discharging OPTIMER capacitor 0.1 0 0.1 A V/t = 50 mV/s; VVINSENSE = 0.78 V 0.48 0.51 0.54 V V/t = 200 mV/s; VVINSENSE = 0.78 V 0.50 0.53 0.56 V zero duty cycle voltage pin CTRL Unit 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) Current sense (pin ISENSE) Vsense(max) maximum sense voltage Vth(sense)opp overpower protection sense threshold voltage 370 400 430 mV VISENSE/t slope compensation V/t = 50 mV/s, high voltage on pin ISENSE power mode - 19 - mV/s tleb leading edge blanking time 250 300 350 ns VVINSENSE = 1 V; Vsense(max) > 400 mV - 0.28 - A VVINSENSE=3 V; Vsense(max) > 400 mV - 1.7 - A 63 55 47 A - Vsense(max) - V 12 - - k Overpower compensation (pin VINSENSE and pin ISENSE) Iopc(ISENSE) overpower compensation current on pin ISENSE 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) TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 14 of 21 TEA1738T; TEA1738LT 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 Isource(DRIVER) source current on pin DRIVER VDRIVER = 2 V - 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). 11. Application information A power supply with the TEA1738(L) is a flyback converter operating in Continuous conduction mode (see Figure 11). Capacitor C5 buffers the IC supply voltage, which is powered via resistor R3 at start-up and via the auxiliary winding during normal operation. Sense resistor R9 converts the current through the MOSFET S1 into a voltage on pin ISENSE. The value of resistor R9 defines the maximum primary peak current in MOSFET S1. Resistor R7 reduces the peak current to capacitor C5. In the example shown in Figure 11, 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 reduces the noise on the CTRL pin. Resistor R7 reduces the peak current to capacitor C5. Resistor R10 is required to limit the current spikes to the DRIVER pin due to parasitic inductance of the current sense resistor R9. TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 15 of 21 TEA1738T; TEA1738LT NXP Semiconductors GreenChip SMPS control IC T1 C1 68 μF D1 R1 10 MΩ D3 C2 100 nF C7 R2 82 kΩ VINSENSE PROTECT R3 1 MΩ 4 6 3 ISENSE DRIVER R5 470 Ω TEA1738T CTRL GND 7 TEA1738LT 2 R4 Θ 200 kΩ OPTIMER O1 5 C3 1 nF C4 220 nF 8 R8 2.2 MΩ 1 S1 R10 Z1 10 Ω R6 O1 VCC 22 kΩ C6 C5 4.7 μF 220 nF R9 0.25 Ω D2 R7 10 Ω 001aan171 Fig 11. Typical application TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 16 of 21 TEA1738T; TEA1738LT 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 1 L 4 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 inches 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 0.244 0.039 0.028 0.041 0.228 0.016 0.024 θ 8o 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 12. Package outline SOT96-1 (SO8) TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 17 of 21 TEA1738T; TEA1738LT NXP Semiconductors GreenChip SMPS control IC 13. Revision history Table 6. Revision history Document ID Release date Data sheet status Change notice Supersedes TEA1738T_TEA1738LT 20101231 Preliminary data sheet - - TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 18 of 21 TEA1738T; TEA1738LT NXP Semiconductors GreenChip SMPS control IC 14. 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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. TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 19 of 21 TEA1738T; TEA1738LT 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] TEA1738T_TEA1738LT Preliminary data sheet All information provided in this document is subject to legal disclaimers. Rev. 1 — 31 December 2010 © NXP B.V. 2010. All rights reserved. 20 of 21 NXP Semiconductors TEA1738T; TEA1738LT 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) . . . . . . . . . . . . . . . 10 Peak power, medium power and low power operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Driver (pin DRIVER) . . . . . . . . . . . . . . . . . . . . 11 OverTemperature Protection (OTP) . . . . . . . . 11 Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . 11 Thermal characteristics . . . . . . . . . . . . . . . . . 12 Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . 12 Application information. . . . . . . . . . . . . . . . . . 15 Package outline . . . . . . . . . . . . . . . . . . . . . . . . 17 Revision history . . . . . . . . . . . . . . . . . . . . . . . . 18 Legal information. . . . . . . . . . . . . . . . . . . . . . . 19 Data sheet status . . . . . . . . . . . . . . . . . . . . . . 19 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Trademarks. . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Contact information. . . . . . . . . . . . . . . . . . . . . 20 Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 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. 2010. 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: 31 December 2010 Document identifier: TEA1738T_TEA1738LT