PT6980

PT6980 TI | Alldatasheet

Document overview

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Technical content

Features

• Dual Outputs (See Ordering Information)
• Ideal Power Source for DSPs
• 12V Input
• Outputs Adjustable
• Remote Sensing (Vo1 & Vo2)
• Standby Function

Description

The PT6980 Excalibur™ series of power modules are dual output integrated switching regulators (ISRs) specifically designed to power mixed signal ICs. Operating from a 12-V input bus, the dual output provides power for both the digital I/O logic and a DSP core from a single module. Both output voltages are internally sequenced during power-up and power- down to comply with the requirements of the latest DSP chips. Each output is inde- pendently adjustable or can be set to at least one alternative bus voltage with a simple pin-strap. The modules are made available in a space-saving solderable case. The features include output current limit and short-circuit protection.

• Soft-Start
• Internal Sequencing
• Short Circuit Protection
• 23-pin Space-Saving Package
• Solderable Copper Case C1 = Req’d 560µF electrolytic C2 = Req’d 330µF electrolytic C3 = Optional 100µF electrolytic PT6980 C 2 GND V IN GND 4,5,6 7-11 12-15 18-21 C 1 C 3 Vo 2 Sense Vo 1 Sense STBY Vo 1 Vo 2 PT6980 Series 10-A 12V-Input Dual Output Integrated Switching Regulator SLTS154 Revised (10/2/2001)

Ordering Information

PT6981/G6F = +2.5/1.8 Volts PT6982/G6F = +3.3/2.5 Volts PT6983/G6F = +3.3/1.8 Volts PT6984/G6F = +3.3/1.2 Volts PT6985/G6F = +2.5/1.2 Volts Pin Function 1V o 1 Sense

2 No Connect

3 STBY

10 GND

11 GND

12 Vo 1

13 Vo 1

14 Vo 1

15 Vo 1

16 Vo 1 Adjust *

17 No Connect

18 Vo 2

19 Vo 2

20 Vo 2

21 Vo 2

22 Vo 2 Sense

23 Vo 2 Adjust *

• Vo1 and V o2 can be pin-strapped to another voltage. See application note on output voltage adjustment. Pin-Out Information PT Series Suffix (PT1234x) Case/Pin Order Package Configuration Suffix Code Vertical N (ELF) Horizontal A (ELG) SMD C (ELH) (Reference the applicable package code drawing for the dimensions and PC layout)

For technical support and more information, see inside back cover or visit www.ti.com PT6980 Series 10-A 12V-Input Dual Output Integrated Switching Regulator Power-up Sequencing and Vo1/Vo2 Loading Power-up Sequencing The PT6980 series of regulators provide two output voltages, Vo1 and Vo2. Each of the output voltage combinations offered by the PT6980 series provides power for both a low- voltage processor core, and the associated digital support circuitry. In addition, each output is internally sequenced during power-up and power-down to comply with the requirements of most DSP and µP IC’s, and their accompa- nying chipsets. Figure 1 shows the typical waveforms of the output voltages, Vo 1 and Vo2, from the instance that either input power is applied or the module is enabled via the Standby pin. Following a delay of about 25 milli-secs, the voltages at Vo 1 and Vo2 rise together until Vo2 reaches its set-point. Then Vo1 continues to rise until both output voltages have reached full voltage. Vo1/Vo2 Loading The output voltages from the PT6980 series regulators are independently regulated. The voltage at Vo1 is produced by a highly efficient switching regulator. The lower output voltage, Vo2, is derived from Vo1. The regulation method used for Vo2 also provides control of this output voltage during power-down. Vo2 will sink current if the voltage at Vo1 attempts to fall below it. The load specifications for each model of the PT6980 series gives both a ‘T ypical’ (T yp) and ‘Maximum’ (Max) load current for each output. For operation within the product’s rating, the load currents at Vo 1 and Vo2 must comply with the following limits:-

• I o 2 must be less than Io2(max).
• The sum-total current from both outputs (Io 1 + Io2) must not exceed Io1(max). In the case that either Vo1 or Vo2 are adjusted to some other value than the default output voltage, the absolute maximum load current for Io 2 must be revised to comply with the following equation. Io2 (max) = 2.5 Adc Vo1 – Vo2 Consult the specification table for each model of the series for the actual numeric values. Figure 1; PT6980 Series Power-up General Specifications (Unless otherwise stated, Ta =25°C, Vin =12V) PT6980 Series Characteristic Symbol Conditions Min Typ Max Units Short Circuit Current I sc Io1 + Io2 combined — 19 — A Switching Frequency ƒ o Over Vin range 500 550 600 kHz Standby (Pin 3) Referenced to GND (pin 7) Input High Voltage V IH — — Open (1) V Input Low Voltage V IL –0.1 — +0.4 Input Low Current I IL — -0.5 – mA Standby Input Current I in standby pin 3 to GND — 4 6 mA External Output Capacitance C 2 330 (2) — 15,000 (2) µFC3 0 — 330 Maximum Operating T a Over Vin Range –40 (3) — +85 (4) °C T emperature Range Storage T emperature T s — –40 — +125 °C Mechanical Shock Per Mil-STD-883D, Method 2002.3 1 msec, ½ Sine, mounted — 500 — G ’s Mechanical Vibration Per Mil-STD-883D, Method 2007.2 20-2000 Hz, Soldered in a PC board — 15 — G ’s Weight — Vertical/Horizontal — 26 — grams Flammability — Meets UL 94V-O Notes: (1) The Standby (pin 3) has an internal pull-up to Vin, and if it is left open circuit the module will operate when input power is applied.Refer to the application notes for interface considerations. (2) The total combined ESR of all output capacitance at 100kHz must be (less than) <50 m Ω . (3) For operating temperatures below 0°C, Cin and Cout must have stable characteristics. Use either tantalum or Oscon® capacitor s. (4) See Safe Operating Area curves for the specific output voltage combination, or contact the factory for the appropriate derat ing. Input/Output Capacitors: The PT6980 series requires a 330µF electrolytic capacitor at both the input and output for proper operation (300µF for Oscon® or low ESR tantalum). In addition, the input capacitance must be rated for a minimum of 1.0Arms ripple current. For transient or dynamic load applications, additional capacitance may be required. Refer to the application notes for more information. V1 (1V/Div) V2 (1V/Div) HORIZ SCALE: 5ms/Div Vstby (10V/Div)

For technical support and more information, see inside back cover or visit www.ti.com PT6981 10.5-A 12V-Input Dual Output Integrated Switching Regulator PT6981 Typical Characteristics Efficiency vs Io1 (See Note A) Vo1 Output Ripple vs Io 1 (See Note A) Power Dissipation vs Io 1 (See Note A) Safe Operating Area, V in =12V (See Note B) Note A: Characteristic data has been developed from actual products tested at 25°C. This data is considered typical data for the Converter. Note B: SOA curves represent the conditions at which internal components are at or below the manufacturer’s maximum operating temperatures 012345678 Io1 (A) Efficiency - % 0.5 1.5 2.5 Io2 (A ) 012345678 Io1 (A) Pd - Watts 2.5 1.5 0.5 0.1 Io2 (A ) 012345678 Io1 (A) [ Io2 fixed at Io2(typ) ] Ripple - mV PT6981 Performance Specifications (Unless otherwise stated, Ta =25°C, Vin =12V, C1 =560µF, C2 =330µF, Io1 =Io1typ, and Io2 =Io2typ) PT6981 (2.5V/1.8V) Characteristic Symbol Conditions Min Typ Max Units Input Voltage Range V in Over Io Range 10.8 — 13.2 VDC Set Point Voltage T olerance V o tol Vo 1 — ±12 ±38 mVVo2 — ±9 ±27 T emperature Variation Reg temp –40° >Ta > +85°C Vo 1 — ±0.5 — %VoVo2 — ±0.5 — Line Regulation Reg line Over Vin range Vo 1 — ±10 ±15 mV Vo2 —± 5± 7 Load Regulation Reg load Over Io range Vo 1 — ±10 ±15 mVVo2 —± 5± 7 T otal Output Voltage Variation ∆Votot Includes set-point, line, load Vo 1 — ±44 — mV–40° >Ta > +85°C Vo 2 — ±28 — Efficiency η —8 0—% Vo Ripple (pk-pk) V r 20MHz bandwidth Vo 1 —3 5— mVppVo2 —3 5— Transient Response t tr 1A/µs load step, 50% to 100% Iotyp — 60 — µs ∆Vtr Vo over/undershoot Vo 1 — ±50 — mVVo2 — ±20 — Notes: (i) Io 1(min) current of 0.1A can be divided between both outputs, V o1 or Vo2. The module will operate at no load with reduced specifications. (ii) The typical current is that which can be drawn simultaneously from both outputs under the stated operating conditions. (iii) The sum of Io1 and Io2 must be less than Io1max, and Io2 must be less than Io2max. 012345678 Io1 (A) [ Io2 fixed at Io2(typ) ] Ambient Temperature (°C) 200LFM 120LFM 60LFM Nat conv Airflow

For technical support and more information, see inside back cover or visit www.ti.com PT6982 10.5-A 12V-Input Dual Output Integrated Switching Regulator PT6982 Typical Characteristics Efficiency vs Io1 (See Note A) Vo1 Output Ripple vs Io 1 (See Note A) Power Dissipation vs Io 1 (See Note A) Safe Operating Area, V in =12V (See Note B) Note A: Characteristic data has been developed from actual products tested at 25°C. This data is considered typical data for the Converter. Note B: SOA curves represent the conditions at which internal components are at or below the manufacturer’s maximum operating temperatures 012345678 Io1 (A) Efficiency - % 1.5 Io2 (A ) 012345678 Io1 (A) Pd - Watts 1.5 0.1 Io2 (A ) 012345678 Io1 (A) [ Io2 fixed at Io2(typ) ] Ripple - mV PT6982 Performance Specifications (Unless otherwise stated, Ta =25°C, Vin =12V, C1 =560µF, C2 =330µF, Io1 =Io1typ, and Io2 =Io2typ) PT6982 (3.3V/2.5V) Characteristic Symbol Conditions Min Typ Max Units Input Voltage Range V in Over Io Range 10.8 — 13.2 VDC Set Point Voltage T olerance V o tol Vo 1 — ±16 ±50 mVVo2 — ±12 ±38 T emperature Variation Reg temp –40° >Ta > +85°C Vo 1 — ±1.0 — %VoVo2 — ±0.5 — Line Regulation Reg line Over Vin range Vo 1 — ±10 ±15 mVVo2 —± 5± 7 Load Regulation Reg load Over Io range Vo 1 — ±10 ±15 mVVo2 — ±10 ±13 T otal Output Voltage Variation ∆Votot Includes set-point, line, load Vo 1 — ±69 — mV–40° >Ta > +85°C Vo 2 — ±39 — Efficiency η —8 4—% Vo Ripple (pk-pk) V r 20MHz bandwidth Vo 1 —3 5— mVppVo2 —3 5— Transient Response t tr 1A/µs load step, 50% to 100% Iotyp — 60 — µs ∆Vtr Vo over/undershoot Vo 1 — ±50 — mVVo2 — ±30 — Notes: (i) Io 1(min) current of 0.1A can be divided between both outputs, V o1 or Vo2. The module will operate at no load with reduced specifications. (ii) The typical current is that which can be drawn simultaneously from both outputs under the stated operating conditions. (iii) The sum of Io1 and Io2 must be less than Io1max, and Io2 must be less than Io2max. 012345678 Io1 (A) [ Io2 fixed at Io2(typ) ] Ambient Temperature (°C) 200LFM 120LFM 60LFM Nat conv Airflow

For technical support and more information, see inside back cover or visit www.ti.com PT6983 9.5-A 12V-Input Dual Output Integrated Switching Regulator PT6983 Typical Characteristics Efficiency vs Io1 (See Note A) Vo1 Output Ripple vs Io 1 (See Note A) Power Dissipation vs Io 1 (See Note A) Safe Operating Area, V in =12V (See Note B) Note A: Characteristic data has been developed from actual products tested at 25°C. This data is considered typical data for the Converter. Note B: SOA curves represent the conditions at which internal components are at or below the manufacturer’s maximum operating temperatures 01234567 Io1 (A) Efficiency - % 1.5 Io2 (A ) 01234567 Io1 (A) Pd - Watts 1.5 0.1 Io2 (A ) 01234567 Io1 (A) [ Io2 fixed at Io2(typ) ] Ripple - mV PT6983 Performance Specifications (Unless otherwise stated, Ta =25°C, Vin =12V, C1 =560µF, C2 =330µF, Io1 =Io1typ, and Io2 =Io2typ) PT6983 (3.3V/1.8V) Characteristic Symbol Conditions Min Typ Max Units Input Voltage Range V in Over Io Range 10.8 — 13.2 VDC Set Point Voltage T olerance V o tol Vo 1 — ±16 ±50 mVVo2 — ±9 ±27 T emperature Variation Reg temp –40° >Ta > +85°C Vo 1 — ±1.0 — %VoVo2 — ±0.5 — Line Regulation Reg line Over Vin range Vo 1 — ±10 ±15 mV Vo2 —± 5± 7 Load Regulation Reg load Over Io range Vo 1 — ±10 ±15 mVVo2 —± 5± 7 T otal Output Voltage Variation ∆Votot Includes set-point, line, load Vo 1 — ±69 — mV–40° >Ta > +85°C Vo 2 — ±28 — Efficiency η —8 1—% Vo Ripple (pk-pk) V r 20MHz bandwidth Vo 1 —3 5— mVppVo2 —3 5— Transient Response t tr 1A/µs load step, 50% to 100% Iotyp — 60 — µs ∆Vtr Vo over/undershoot Vo 1 — ±50 — mVVo2 — ±20 — Notes: (i) Io 1(min) current of 0.1A can be divided between both outputs, V o1 or Vo2. The module will operate at no load with reduced specifications. (ii) The typical current is that which can be drawn simultaneously from both outputs under the stated operating conditions. (iii) The sum of Io1 and Io2 must be less than Io1max, and Io2 must be less than Io2max. 01234567 Io1 (A) [ Io2 fixed at Io2(typ) ] Ambient Temperature (°C) 200LFM 120LFM 60LFM Nat conv Airflow

For technical support and more information, see inside back cover or visit www.ti.com PT6984 8.6-A 12V-Input Dual Output Integrated Switching Regulator PT6984 Typical Characteristics Efficiency vs Io1 (See Note A) Vo1 Output Ripple vs Io 1 (See Note A) Power Dissipation vs Io 1 (See Note A) Note A: Characteristic data has been developed from actual products tested at 25°C. This data is considered typical data for the Converter. Note B: SOA curves represent the conditions at which internal components are at or below the manufacturer’s maximum operating temperatures PT6984 Performance Specifications (Unless otherwise stated, Ta =25°C, Vin =12V, C1 =560µF, C2 =330µF, Io1 =Io1typ, and Io2 =Io2typ) PT6984 (3.3V/1.2V) Characteristic Symbol Conditions Min Typ Max Units Input Voltage Range V in Over Io Range 10.8 — 13.2 VDC Set Point Voltage T olerance V o tol Vo 1 — ±16 ±50 mVVo2 — ±6 ±18 T emperature Variation Reg temp –40° >Ta > +85°C Vo 1 — ±1.0 — %VoVo2 — ±0.5 — Line Regulation Reg line Over Vin range Vo 1 — ±10 ±15 mV Vo2 —± 5± 7 Load Regulation Reg load Over Io range Vo 1 — ±10 ±15 mVVo2 —± 5± 7 T otal Output Voltage Variation ∆Votot Includes set-point, line, load Vo 1 — ±69 — mV–40° >Ta > +85°C Vo 2 — ±22 — Efficiency η —7 8—% Vo Ripple (pk-pk) V r 20MHz bandwidth Vo 1 —3 5— mVppVo2 —3 5— Transient Response t tr 1A/µs load step, 50% to 100% Iotyp — 60 — µs ∆Vtr Vo over/undershoot Vo 1 — ±50 — mVVo2 — ±20 — Notes: (i) Io 1(min) current of 0.1A can be divided between both outputs, V o1 or Vo2. The module will operate at no load with reduced specifications. (ii) The typical current is that which can be drawn simultaneously from both outputs under the stated operating conditions. (iii) The sum of Io1 and Io2 must be less than Io1max, and Io2 must be less than Io2max. 01234567 Io1 (A) Efficiency - % 0.5 0.75 1.25 1.6 Io2 (A ) 01234567 Io1 (A) [ Io2 fixed at Io2(typ) ] Ripple - mV 01234567 Io1 (A) Pd - Watts 1.6 1.25 1.0 0.75 0.5 0.1 Io2 (A ) Safe Operating Area, V in =12V (See Note B) 01234567 Io1 (A) [ Io2 fixed at Io2(typ) ] Ambient Temperature (°C) 200LFM 120LFM 60LFM Nat conv Airflow

For technical support and more information, see inside back cover or visit www.ti.com PT6985 9-A 12V-Input Dual Output Integrated Switching Regulator PT6985 Typical Characteristics Efficiency vs Io1 (See Note A) Vo1 Output Ripple vs Io 1 (See Note A) Power Dissipation vs Io 1 (See Note A) Note A: Characteristic data has been developed from actual products tested at 25°C. This data is considered typical data for the Converter. Note B: SOA curves represent the conditions at which internal components are at or below the manufacturer’s maximum operating temperatures 01234567 Io1 (A) Efficiency - % 1.5 Io2 (A ) 01234567 Io1 (A) [ Io2 fixed at Io2(typ) ] Ripple - mV 01234567 Io1 (A) Pd - Watts 1.5 0.1 Io2 (A ) PT6985 Performance Specifications (Unless otherwise stated, Ta =25°C, Vin =12V, C1 =560µF, C2 =330µF, Io1 =Io1typ, and Io2 =Io2typ) PT6985 (2.5V/1.2V) Characteristic Symbol Conditions Min Typ Max Units Output Current Io 1 Ta =25°C, natural convection Vo 1 (2.5V) 0.1 (i) 7 (ii) 9 (iii) AIo2 Vo2 (1.2V) 0 2 (ii) 2.2 (iii) Io1 Ta =60°C, 200LFM airflow Vo 1 (2.5V) 0.1 (i) 7 (ii) 9 (iii) AIo2 Vo2 (1.2V) 0 2 (ii) 2.2 (iii) Input Voltage Range V in Over Io Range 10.8 — 13.2 VDC Set Point Voltage T olerance V o tol Vo 1 — ±12 ±38 mVVo2 — ±6 ±18 T emperature Variation Reg temp –40° >Ta > +85°C Vo 1 — ±0.5 — %VoVo2 — ±0.5 — Line Regulation Reg line Over Vin range Vo 1 — ±10 ±15 mV Vo2 —± 5± 7 Load Regulation Reg load Over Io range Vo 1 — ±10 ±15 mVVo2 —± 5± 7 T otal Output Voltage Variation ∆Votot Includes set-point, line, load Vo 1 — ±44 — mV–40° >Ta > +85°C Vo 2 — ±22 — Efficiency η —7 7—% Vo Ripple (pk-pk) V r 20MHz bandwidth Vo 1 —3 5— mVppVo2 —3 5— Transient Response t tr 1A/µs load step, 50% to 100% Iotyp — 60 — µs ∆Vtr Vo over/undershoot Vo 1 — ±50 — mVVo2 — ±20 — Notes: (i) Io 1(min) current of 0.1A can be divided between both outputs, V o1 or Vo2. The module will operate at no load with reduced specifications. (ii) The typical current is that which can be drawn simultaneously from both outputs under the stated operating conditions. (iii) The sum of Io1 and Io2 must be less than Io1max, and Io2 must be less than Io2max. Safe Operating Area, V in =12V (See Note B) 01234567 Io1 (A) [ Io2 fixed at Io2(typ) ] Ambient Temperature (°C ) 200LFM 120LFM 60LFM Nat conv Airflow

For technical support and more information, see inside back cover or visit www.ti.com Table 1: Input/Output Capacitors N/R –Not recommended. The voltage rating does not meet the minimin operating limits. Capacitor Recommendations for the Dual-Output PT6980 Regulator Series Input Capacitors: The recommended input capacitance is determined by 1.0 ampere minimum ripple current rating and 330µF minimum capacitance . Ripple current and <100mΩ equivalent se- ries resistance (ESR) values are the major considerations, along with temperature, when designing with different types of capacitors. T antalum capacitors have a recommended minimum voltage rating of 2 × the maximum DC voltage + AC ripple. This is necessary to insure reliability for input voltage bus applications Output Capacitors: C 2(Required), C3(Optional) The ESR of the required capacitor (C2) must not be greater than 50mΩ . Electrolytic capacitors have poor ripple per- formance at frequencies greater than 400kHz but excellent low frequency transient response. Above the ripple fre- quency, ceramic capacitors are necessary to improve the transient response and reduce any high frequency noise components apparent during higher current excursions. Preferred low ESR type capacitor part numbers are identified in Table 1. The optional 100µF capacitor (C 3) for V2out can have an ESR of up to 200mΩ for optimum performance and ripple reduction. (Note: Vendor part numbers for the optional capacitor, C3, are not identified in the table. Use the same series selected for C2) PT6980 Series Tantalum Capacitors Tantalum type capacitors may be used at the output, but only the AVX TPS series, Sprague 593D/594/595 series, or Kemet T495/T510 series. The AVX TPS series, Kemet or Sprague series tantalums are recommended over many other types due to their higher rated surge, power dissipation, and ripple current capability. As a caution, the TAJ series by AVX is not recommended. This series has considerably higher ESR, reduced power dissipation and lower ripple current capability. The TAJ Series is also less reliable than the AVX TPS series when determining power dissipation capability. T antalum or Oscon® types are recommended for applications where ambient temperatures fall below 0°C. Capacitor Table Table 1 identifies the characteristics of capacitors from a number of vendors with acceptable ESR and ripple current (rms) ratings. The number of capacitors required at both the input and output buses is identified for each capacitor type. This is not an extensive capacitor list. Capacitors from other vendors are available with comparable specifications. Those listed are for guidance. The RMS ripple current rating and ESR (Equivalent Series Resistance at 100kHz) are critical parameters necessary to insure both optimum regulator performance and long capacitor life. Application Notes roticapaC /rodneV tnenopmoC seireS scitsiretcarahCroticapaCy titnauQ gnikroW egatloV) Fµ(eulaV tnelaviuqE)RSE( ecnatsiseRseireS elppiRmumixaMC°58 )smrI(tnerruC lacisyhP )mm(eziS tupnI suB tuptuO suB rebmuNrodneV cinosanaP CF V53 V53 V05 Fµ086 Fµ065 Fµ086 340.0 Ω 830.0 Ω 840.0 Ω Am0961 Am5561 Am5381 51x61 02x5.21 02x61 S186V1CFUEE S165V1CFUEE 186H1CFUEE detinU noc-imehC /ZXL/VXL SF/XF V53 V05 V01 V02 Fµ086 Fµ086 Fµ093 Fµ051 830.0 Ω 840.0 Ω 030.0 Ω 420.0 Ω Am0661 Am0481 Am0803 Am0023 02x5.21 02x61 5.01x8 5.01x8 R/N LL02X211M186BV53ZXL LL02X61M186BV05ZXL M093XF01 M051XF02 nocihciN /LP MP V53 V52 V53 065F µ 028F µ 065F µ 840.0 Ω 940.0 Ω 8400.0 Ω Am0631 Am0431 Am0631 51x61 51x61 51x61 6HHM165V1LPU 6HHM128E1LPU 6HHM165V1MPU cinosanaP CF gtMecafruS V53 V53 V53 033F µ 0001F µ 074F µ 560.0 ÷2Ω 830.0 Ω 340.0 Ω Am5021> Am0002 Am0961 5.61x5.21 5.61x81 5.61x61 QL133V1CFVEE N1201V1CFVEE N174V1CFVEE /SSnocsOV S V01 V01 033F µ Fµ033 520.0 Ω 520.0 Ω Am0053> Am0083> 5.01x0.01 3.01x3.01 R/N R/N M033SS01 M033VS01 )VS(tnuoMecafruS XVA mulatnaT SPT V01 V01 Fµ033 Fµ022 060.0 ÷2Ω 060.0 ÷2Ω Am0052> Am0003> xL3.7 xW3.4 R/N R/N 0600R010M733VSPT 0600R010M722VSPT temeK 015T 594T V01 V01 Fµ033 Fµ022 330.0 Ω 70.0 Ω÷ 530.0=2 Ω Am0041 Am0002> W7.5xL3.7 H0.4x R/N R/N SA010M733X015T SA010M722X594T eugarpS D495 V01F µ0335 40.0 Ω Am0532 xL3.7 xW0.6 H1.4 R/N1 T 2R0100X733D495

For technical support and more information, see inside back cover or visit www.ti.com Adjusting the Output Voltage of the PT6980 Dual-Output Voltage Regulators Each output voltage from the PT6980 series of integrated switching regulators (ISRs) can be independently adjusted higher or lower than the factory trimmed pre-set voltage. The voltages, Vo 1 and Vo2 may be adjusted either up or down using a single external resistor 1. T able 1 gives the adjustment range for both Vo1 and Vo2 for each model in the series as Va(min) and Va(max). Note that Vo2 must always be lower than Vo1 2. Vo1 Adjust Up: T o increase the output, add a resistor R4 between pin 16 (V1 Adjust) and pins 7-11 (GND) 1. Vo1 Adjust Down:Add a resistor (R3), between pin 16 (Vo1 Adjust) and pin 1 (Vo1 Sense) 1. Vo2 Adjust Up: Add a resistor R2 between pin 23 (Vo2 Adjust) and pins 7-11 (GND) 1. Vo2 Adjust Down:Add a resistor (R1) between pin 23 (Vo2 Adjust) and pin 22 (Vo2 Sense) 1. Refer to Figure 1 and Table 2 for both the placement and value of the required resistor. Notes: 1. Use only a single 1% resistor in either the (R3) or R4 location to adjust Vo1, and in the (R1) or R2 location to adjust Vo2. Place the resistor as close to the ISR as possible. 2. Vo 2 must always be at least 0.2V lower than Vo1. Figure 1 C 1 C 2 C 3 (R3) (R1) L O A D L O A D Adj Down Adjust Up V IN COM COM Vo 2 Vo 1 PT6980 18 - 21 237 - 11 4,5,6 Vin Vo 2 GND Vo 2 (adj) Vo 1 (sns) Vo 1 (adj) 12 - 15Vo 1 Vo 2 (sns) STBY Adjust Vo1 Adjust Vo2 3. Both the Vo1 and Vo2 may be adjusted down to an alternative bus voltage by making, (R3) or (R1) respectively, a zero ohm link. Refer to the T able 1 footnotes for guidance. 4. Never connect capacitors to either the Vo 1 Adjust or Vo2 Adjust pins. Any capacitance added to these control pins will affect the stability of the respective regulated output. 5. Adjusting either voltage (Vo 1 or Vo2) may increase the power dissipation in the regulator, and change the maximum current available at either output. Consult the note on p.2 of the data sheet regarding Vo 1/Vo2 loading. The adjust up and adjust down resistor values can also be calculated using the following formulas. Be sure to select the correct formula parameter from T able 1 for the output and model being adjusted. (R1) or (R3) = 10 (Va – Vr ) – Rs kΩ Vo – Va (R2) or (R4) = 10 · Vr – Rs kΩ Va – Vo Where: V o = Original output voltage, (Vo1 or Vo2) Va = Adjusted output voltage Vr = The reference voltage from T able 1 Rs = The series resistance from T able 1 PT6980 Series

For technical support and more information, see inside back cover or visit www.ti.com Application Notes 1.8 (0.0) 1.85 (1.4)kΩ 1.9 (3.0)kΩ 1.95 (4.9)kΩ 2.0 (7.1)kΩ 2.05 (9.8)kΩ 2.1 (13.3)kΩ 2.2 (23.5)kΩ 2.3 (44.0)kΩ 2.4 (106.0)kΩ 2.5 (0.0)kΩ 2.6 120.0k Ω (3.6)kΩ 2.8 34.8k Ω (15.2)kΩ 2.9 24.3k Ω (25.4)kΩ 3.0 17.9k Ω (42.3)kΩ 3.1 13.7k Ω (76.1)kΩ 3.2 10.6k Ω (178.0)kΩ 3.3 8.4k Ω 3.4 6.6k Ω 112.0k 3.5 5.2k Ω 48.1k 3.6 4.1k Ω 26.9k R1/R3 = (Blue), R2/R4 = Black Vo1 Bus Series Pt # PT6981/85 PT6982/83/84 Adj. Resistor (R3)/R4 (R3)/R4 Vo(nom) 2.5V 3.3V Va(req’d) Table 1 ADJUSTMENT RANGE AND FORMULA PARAMETERS Vo1 Bus Vo 2 Bus (2) Series Pt # PT6981/85 PT6982/83/84 PT6984/85 PT6981/83 PT6936 Adj. Resistor (R3)/R4 (R3)/R4 (R1)/R2 (R1)/R2 (R1)/R2 Ref. Note 3: * (R3) = Zero-ohm link †(R1) = Zero-ohm link # (R2) = Zero-ohm link 1.0 (0.0)kΩ 1.05 (9.2)kΩ 1.1 (28.8)kΩ 1.15 (87.5)kΩ 1.2 1.25 101.5k Ω 1.3 41.2k Ω 1.35 20.8kΩ 1.4 10.6k Ω 1.45 4.5k Ω 1.5 0.0k Ω (0.0)kΩ 1.55 (5.1)kΩ 1.6 (13.1)kΩ 1.65 (26.4)kΩ 1.7 (53.1)kΩ 1.75 (133.0)kΩ 1.8 (0.0)kΩ 1.85 183.0k Ω (1.6)kΩ 2.05 23.1kΩ (11.8)kΩ 2.1 16.4k Ω (16.0)kΩ 2.4 0.0k Ω (129.0)kΩ 2.5 2.6 88.5k Ω 2.7 38.5k Ω 2.8 21.8k Ω 2.9 13.5k Ω 3.0 8.5k Ω Vo2 Bus Series Pt # PT6984/85 PT6981/83 PT6982 Adj. Resistor (R1)/R2 (R1)/R2 (R1)/R2 Vo(nom) 1.2V 1.8V 2.5V Va(req’d) Table 2 ADJUSTMENT RESISTOR VALUES PT6980 Series

For technical support and more information, see inside back cover or visit www.ti.com PT6980 Series Using the Standby Function on the PT6980 Series of Dual-Output Voltage Regulators Both output voltages of the 23-pin PT6980 dual-output converter may be disabled using the regulator’s ‘Standby’ function. This function may be used in applications that require power-up/shutdown sequencing, or wherever there is a requirement to control the output voltage On/Off status with external circuitry. The standby function is provided by the STBY* control (pin 3). If pin 3 is left open-circuit the regulator operates normally, and provides a regulated output at both Vo 1 (pins 12–15) and Vo2 (pins 18–21) whenever a valid supply volt- age is applied to Vin (pins 4, 5, & 6) with respect to GND (pins 7-11). If a low voltage1 is then applied to pin-3 both regulator outputs will be simultaneously disabled and the input current drawn by the ISR will drop to a typical value of 4mA. The standby control may also be used to hold-off both regulator outputs during the period that input power is applied. The standby pin is ideally controlled using an open-collector (or open-drain) discrete transistor (See Figure 1). The open-circuit voltage is the input voltage +V in. T able 1 gives the circuit parameters for this control input. Table 1 Standby Control Parameters 1, 2 Parameter Min TYP Max Enable (VIH) — — Open circuit Disable (VIL) –0.1V — 0.4V 1 VSTBY (open circuit) — +V in 2 — ISTBY (IIL) — — –0.5mA Notes: 1. The standby control input is Not compatible with TTL or other devices that incorporate a totem-pole output drive. Use only a true open-collector device, preferably a discrete bipolar transistor (or MOSFET). T o ensure the regulator output is disabled, the control pin must be pulled to less than 0.4Vdc with a low-level 0.5mA sink to ground.

2 The standby control input

requires no external pull-up resistor. The open-circuit voltage of the STBY* pin is the input voltage +Vin. 3. When the regulator output is disabled the current drawn from the input source is typically reduced to 4mA. Figure 1 Turn-On Time: Turning Q1 in Figure 1 off removes the low- voltage signal at pin 3 and enables the PT6980 series regulator. Following a delay of about 25ms, Vo 1 and Vo2 rise together until the lower voltage, Vo 2, reaches its set output. Vo1 continues to rise until both outputs reach full regulation voltage. The total power-up time is less than 40ms, and is relatively independent of load, temperature, and output capacitance. Figure 2 shows waveforms of the output voltages, Vo 1 and Vo2, for a PT6984 (3.3V/1.2V). The turn-off of Q1 corresponds to the rise in VSTBY. The waveforms were measured with a 12V input voltage, and with resistive loads of 5A and 1.25A at the Vo 1 and Vo2 outputs respectively. Figure 2 C 1 C 2 Inhibit V in Vo 2 COMCOM BSS138 Vo 1 C 3 4, 5, 6 PT6984 18–21 237–11 V IN Vo 2 GND V 2 (adj) V 1 (sns) V 1 (adj) 12–15Vo 1 V 2 (sns) STBY V1 (1V/Div) V2 (1V/Div) HORIZ SCALE: 5ms/Div Vstby (10V/Div)

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