tea1781 NXP Semiconductors, tea1781 Datasheet
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tea1781 Summary of contents
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... GreenChip PC secondary control ICs Rev. 01 — 13 February 2009 1. General description The TEA1781T and TEA1782T are designed to cooperate with the TEA1771T primary side controller in a unique converter topology based on the active clamp forward converter. On the secondary side the output voltages are regulated via bidirectional switches ...
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... TEA1782T SO28 TEA1781_82_1 Preliminary data sheet Description Plastic small outline package; 28 leads; body width 7.5 mm Plastic small outline package; 28 leads; body width 7.5 mm Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs © NXP B.V. 2009. All rights reserved. Version SOT136-1 SOT136 ...
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... Temperature protection I ENABLE V trip(ENABLE) Control trip Drive SR Drive 5 V VDD Fig 1. TEA1781T block diagram TEA1781_82_1 Preliminary data sheet 9 22 PowerGood PowerOK V otp PGOOD I-control Control 3.3 V ref(5V V/I S V/I Protection > ocp ...
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... OCP 5 CS_5V 6 7 VOUT_5V TEA1781T VSENSE_5V 8 VNTC 9 ENABLE 10 11 PGND_5V GSF_5V 12 GND 13 14 GND 014aaa183 Fig 3. TEA1781T pin configuration TEA1781_82_1 Preliminary data sheet PS_OFF Digital control V > V VDD startup(VDD) V < V VDD stop(VDD) STARTUP ENABLE V > V VDD startup(VDD) V ENABLE I > I ...
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... Table 3. Symbol FSB_12V GSB_12V DF_12V OCP_12V CS_12V VOUT_12V1 VOUT_12V2 EN_NM TEA1781_82_1 Preliminary data sheet TEA1781T pin description Pin Description 1 floating supply switch SB_5V 2 gate driver switch SB_5V 3 drain voltage of switch SF_5V 4 start-up voltage connected to rectified secondary winding voltage 5 overcurrent protection ...
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... Standby mode but keep the 5 V standby in operation, a separate standby supply is still common practice. With the GreenChip PC chip set (TEA1771T, TEA1781T, TEA1782T) a system configuration is introduced that integrates the post regulation and combines the main and standby converter into a single system. This high level of integration reduces the total cost of the system ...
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... To fulfill the ATX12V specification on standby efficiency requirements, the system has a Standby mode in which the frequency, duty cycle and supply currents are reduced. The TEA1781T and TEA1782T are secondary control ICs. Together with the TEA1771T primary controller they form a unique system that fulfills the 80+ gold requirements at minimum costs, eliminating any cross regulation and maximizing standby effi ...
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... and 12 V). The 12 V (and 12 V) output is regulated by the TEA1782T itself, whereas the 3.3 V and 5 V output are regulated by the TEA1781T. The TEA1781T activates the 3.3 V and 5 V outputs via the ENABLE signal. TEA1781_82_1 Preliminary data sheet startup(VDD) , the output voltage slowly ramps up from zero to the required value ...
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... WND_SEC_2 Enable Normal mode assures a proper start-up of the forward converter must be built between the PS_ON# signal from the motherboard and the Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs , the IC enters the Start-up stop(VDD) Enable NM Digital control EN_NM 1 ...
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... The TEA1782T is the master of the system. The required duty cycle is communicated to the primary controller TEA1771T via the opto coupler. The TEA1782T communicates to the TEA1781T via the enable signal, see disabled. If the system is in Normal mode, the voltage of the enable signal exceeds the ...
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... TEA1781_82_1 Preliminary data sheet ENABLE V trip(ENABLE) I ENABLE temp.prot protection 5 V protection 3.3 V TEA1781 The ENABLE signal is for communicating between the secondary control ICs Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs Digital control V < V STARTUP VDD stop(VDD ENABLE V VDD ...
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... V higher than the secondary transformer voltage at the appropriate time. As the source of the rectifying switch SR is connected to the transformer, which can be either negative or positive, the TEA1781T and TEA1782T are developed in a special process (ABCD - SOI) which is capable of handling these (high) negative and positive voltages. ...
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... The “x” for these pins and symbols stands for either 3V3 12V Figure 11. Once the secondary side transformer voltage is positive L the voltage across the parallel capacitor equals the ----- - R L Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs V WND_SEC_x ResetSB VOUT_x represent the inductance and the L ...
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... Fig 12. PowerOK circuit diagram The PGOOD output is pulled down by the TEA1781T when either the 3 below its lower limit the TEA1782T when the below its lower limit. When all main outputs are above their minimum value, the PGOOD signal slowly rises from zero to the VDD level ...
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... OPTO Figure 13. OPTO control UP S1 DOWN S2 (Normal mode). In this mode, the primary duty cycle is defined by the OPTO Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs I OPTO 3 off PVCC S3 S4 ...
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... ENABLE is pulled down and as a result both the TEA1782T and the TEA1781T will disable the main outputs. The 5 V standby output remains on OVP or OCP is detected in the TEA1781T and communicated to the TEA1782 via the pin ENABLE result the TEA1782T will pull down the pin ENABLE, disabling all main outputs ...
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... The OCP levels can be set externally. The maximum output current of the 12 V1 and 12 V2 are supposed to be about equal, therefore have the same OCP setting. gives the 12 V OCP block diagram. TEA1781_82_1 Preliminary data sheet TEA1781T; TEA1782T GreenChip PC secondary control ICs Rev. 01 — 13 February 2009 Figure 15 © NXP B.V. 2009. All rights reserved. ...
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... RC network across the output inductor, making use of the inductor series resistance. If either the 3.3 V output exceeds its OCP setting, the system enters the Protection mode. TEA1781_82_1 Preliminary data sheet TEA1781T; TEA1782T GreenChip PC secondary control ICs Protection mode Protection ...
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... Standby mode. 7.12.5 Overtemperature protection The system will enter the Protection mode at an initialized temperature level via an external NTC network connected to the VNTC pin of the TEA1781T. In this way the system can be protected against overtemperature. TEA1781_82_1 Preliminary data sheet ...
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... VOUT_5V voltage on pin VSENSE_5V voltage on pin VNTC voltage on pin ENABLE voltage on pin PGND_5V supply voltage voltage on pin PGND_3V3 voltage on pin PWROK Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs ( 500 s)) the system still d(restart) Min Max 7 +40 0.4 +75 250 +80 0.4 +7 ...
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... EN_NM voltage on pin PS_OFF voltage on pin PGND_12V supply voltage voltage on pin PGND_STB voltage on pin PGOOD voltage on pin VOUT_STB voltage on pin CS_STB current on pin OCP_STB Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs Min Max 0.4 +7 0.4 +7 0 +40 40 +40 < ...
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... Thermal characteristics Parameter thermal resistance from junction to ambient can be lower when pin GND is connected to sufficient copper area on the th(j-a) Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs Min Max 0.8 +73 73 +73 < <tbd> ...
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... NXP Semiconductors 10. Characteristics Table 7. TEA1781T characteristics over temperature; all voltages are measured with respect to ground; currents are positive when flowing into amb the IC; unless otherwise specified. Symbol Parameter Supply V regulation voltage on pin reg(VDD) VDD I current on pin VDD VDD ...
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... NXP Semiconductors Table 7. TEA1781T characteristics over temperature; all voltages are measured with respect to ground; currents are positive when flowing into amb the IC; unless otherwise specified. Symbol Parameter I current on pin ENABLE ENABLE Soft start t soft start time start(soft) PGOOD and PWROK ...
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... WND_SEC_1 enable GSB 12 V; voltage on pin WND_SEC_1 enable GSR; voltage on pin DF enable GSB 12 V; voltage on pin WND_SEC_1 enable GSR; voltage on pin DF enable GSB 100 mV CS_x VOUT Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs Min Typ Max 8.0 8.5 9.0 6.9 7.4 7.9 - 3.0 - ...
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... OUT_12V OUT_STB system to Standby mode Normal mode Standby mode Normal mode Standby mode Normal mode; Protection mode V = 0.4 V PGOOD OPTO Standby mode Normal mode system restart Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs Min Typ Max 11.7 12.1 12.4 [1] 11.5 11.9 12 1.14 1.20 1.26 ...
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... If so, then that is preferred here activating current CS_STB VOUT_STB protection during soft start; OCP_STB = n. activating current CS_12V VOUT_12V protection during soft start; OCP_12V = n.c. Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs Min Typ Max [1] 155 180 205 [1] 320 380 440 be CS [1] ...
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... TEA1782 B_12V S F_12V Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs VOUT_3V3 PWROK ntc 14 VOUT_5V VOUT_STB PS_ON# 14 VOUT_12V2 VOUT_12V1 014aaa755 © NXP B.V. 2009. All rights reserved ...
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... 0.49 0.32 18.1 7.6 10.65 1.27 0.36 0.23 17.7 7.4 10.00 0.019 0.013 0.71 0.30 0.419 0.05 0.014 0.009 0.69 0.29 0.394 REFERENCES JEDEC JEITA MS-013 Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs detail 1.1 1.1 0.25 0.25 1.4 0.4 1.0 0.043 0.043 0.01 0.01 0.055 ...
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... NXP Semiconductors 13. Revision history Table 9. Revision history Document ID Release date TEA1781_82_1 20090213 TEA1781_82_1 Preliminary data sheet TEA1781T; TEA1782T Data sheet status Change notice Preliminary data sheet - Rev. 01 — 13 February 2009 GreenChip PC secondary control ICs Supersedes - © NXP B.V. 2009. All rights reserved. ...
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... Notice: All referenced brands, product names, service names and trademarks are the property of their respective owners. GreenChip — trademark of NXP B.V. http://www.nxp.com salesaddresses@nxp.com Rev. 01 — 13 February 2009 TEA1781T; TEA1782T GreenChip PC secondary control ICs © NXP B.V. 2009. All rights reserved ...
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... 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. 2009. For more information, please visit: http://www.nxp.com For sales office addresses, please send an email to: salesaddresses@nxp.com All rights reserved. Date of release: 13 February 2009 Document identifier: TEA1781_82_1 ...