ACT8798 Rev0, 10-Oct-08 Six Channel Integrated Power Management IC for Handheld Portable Equipment FEATURES GENERAL DESCRIPTION • Multiple Patents Pending • Six Integrated Regulators The patent-pending ACT8798 is a complete, costeffective, highly-efficient ActivePMUTM power management solution that is ideal for a wide range of portable handheld equipment. This device integrates three step-down DC/DC converters and three low dropout linear regulators (LDOs) into a single, thin, space-saving package. An I2C Serial Interface provides programmability for the DC/DC converters and LDOs. − 1.2A PWM Step-Down DC/DC − 1.2A PWM Step-Down DC/DC − 750mA PWM Step-Down DC/DC − 250mA Low Noise LDO − 250mA Low Noise LDO − 250mA Low Noise LDO • I2CTM Compatible Serial Interface REG1, REG2 and REG3 are fixed-frequency, current-mode PWM step-down DC/DC converters that are optimized for high efficiency and are capable of supplying up to 1.2A, 1.2A and 750mA, respectively. REG4, REG5 and REG6 are low noise, high PSRR linear regulators that are capable of supplying up to 250mA each. − Programmable Output Voltages − Configurable Operating Modes • Minimal External Components • 4x4mm, Thin-QFN (TQFN44-24) Package − Only 0.75mm Height − RoHS Compliant The ACT8798 is available in a tiny 4mm x 4mm 24pin Thin-QFN package that is just 0.75mm thin. APPLICATIONS • Portable Devices and PDAs • Wireless Handhelds • DMB Enabled Devices • GPS Receivers, etc. SYSTEM BLOCK DIAGRAM REG2 Battery Step-Down DC/DC nMSTR nRSTO PWRHLD ON3 REG3 System Control Step-Down DC/DC SCL REG4 SDA OUT1 1.1V to 4.4V Up to 1.2A LDO REG1 REG5 Step-Down DC/DC LDO REG6 ACT8798 PMU LDO TM Active Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. -1- OUT2 1.1V to 4.4V Up to 1.2A OUT3 1.1V to 4.4V Up to 750mA OUT4 0.645V to 3.7V Up to 250mA Pb-free OUT5 1.4V to 3.7V Up to 250mA OUT6 1.4V to 3.7V Up to 250mA www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 FUNCTIONAL BLOCK DIAGRAM VP1 To Battery ACT8798 SCL SW1 REG1 Serial Interface SDA OUT1 OUT1 GP12 VP2 To Battery INL SW2 REG2 nMSTR OUT2 OUT2 PUSH BUTTON GP12 OUT2 VP3 To Battery nRSTO REG3 SW3 PWRHLD OUT3 System Control OUT3 GP3 ON3 INL To Battery LDO REG4 OUT4 OUT4 REFBP Reference LDO REG5 OUT5 OUT5 GA LDO REG6 Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. -2- OUT6 OUT6 www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 ORDERING INFORMATIONcd PART NUMBER ACT8798QLGHW-T VOUT1 VOUT2 VOUT3 3.0V 3.3V 1.35V VOUT4 VOUT5 VOUT6 PACKAGE 1.35V 2.8V 1.8V PINS TEMPERATURE RANGE 24 -40°C to +85°C TQFN44-24 OUTPUT VOLTAGE CODES (VOUT1 AND VOUT2) C D E F G H I 1.2V 1.5V 1.8V 2.5V 3.0V 3.3V 2.8V c: Output voltage options detailed in this table represent standard voltage options, and are available for samples or production orders. Additional output voltage options, as detailed in the Output Voltage Codes table, are available for production subject to minimum order quantities. Contact Active-Semi for more information regarding semi-custom output voltage combinations. d: All Active-Semi components are RoHS Compliant and with Pb-free plating unless specified differently. The term Pb-free means semiconductor products that are in compliance with current RoHS (Restriction of Hazardous Substances) standards. PIN CONFIGURATION TOP VIEW INL OUT6 OUT5 GP3 SW3 VP3 24 23 22 21 20 19 OUT4 1 18 OUT3 SCL 2 17 GA SDA 3 16 REFBP GA 4 nMSTR 5 nRSTO 6 15 PWRHLD ACT8798 14 ON3 EP 10 11 12 GP12 SW2 VP2 9 SW1 OUT1 8 VP1 7 13 OUT2 Thin - QFN (TQFN44-24) Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. -3- www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 PIN DESCRIPTIONS PIN NAME DESCRIPTION 1 OUT4 2 SCL Clock Input for I2C Serial Interface. Data is read on the rising edge of the clock. 3 SDA Data Input for I2C Serial Interface. Data is read on the rising edge of the clock. 4, 17 GA 5 nMSTR Master Enable Input. Drive nMSTR to GA or to a logic low to enable the IC. REG1, REG2, and REG3 are enabled while nMSTR is asserted. 6 nRSTO Open-Drain Reset Output. nRSTO asserts low for the reset timeout period of 300ms whenever the IC is enabled. 7 OUT1 Output Feedback Sense for REG1. Connect this pin directly to the output node to connect the internal feedback network to the output voltage. 8 VP1 Power Input for REG1. Bypass to GP12 with a high quality ceramic capacitor placed as close as possible to the IC. 9 SW1 Switching Node Output for REG1. Connect this pin to the switching end of the inductor. 10 GP12 Power Ground for REG1 and REG2. Connect GA, GP12, and GP3 together at a single point as close to the IC as possible. 11 SW2 Switching Node Output for REG2. Connect this pin to the switching end of the inductor. 12 VP2 Power Input for REG2. Bypass to GP12 with a high quality ceramic capacitor placed as close as possible to the IC. 13 OUT2 Output Feedback Sense for REG2. Connect this pin directly to the output node to connect the internal feedback network to the output voltage. 14 ON3 Enable Input for REG3, ON3 is functional only when PWRHLD is driven high. Drive ON3 to a logic high to turn on the REG3. Drive ON3 to a logic low to turn off the REG3. 15 PWRHLD Power Hold Input. Drive PWRHLD to logic high to enable the IC. Drive PWRHLD to a logic low to disable all regulators. 16 REFBP Reference Noise Bypass. Connect a 0.01µF ceramic capacitor from REFBP to GA. This pin is discharged to GA in shutdown. 18 OUT3 Output Feedback Sense for REG3. Connect this pin directly to the output node to connect the internal feedback network to the output voltage. 19 VP3 Power Input for REG3. Bypass to GP3 with a high quality ceramic capacitor placed as close as possible to the IC. 20 SW3 Switching Node Output for REG3. Connect this pin to the switching end of the inductor. 21 GP3 Power Ground for REG3. Connect GA, GP12, and GP3 together at a single point as close to the IC as possible. 22 OUT5 Output Voltage for REG5. Capable of delivering up to 250mA of output current. The output is discharged to G with 650Ω load when disabled. 23 OUT6 Output Voltage for REG6. Capable of delivering up to 250mA of output current. The output is discharged to G with 650Ω load when disabled. 24 INL Power Input for REG4, REG5 and REG6. Bypass to GA with a high quality ceramic capacitor placed as close as possible to the IC. EP EP Exposed Pad. Must be soldered to ground on PCB. Output Voltage for REG4. Capable of delivering up to 250mA of output current. The output is discharged to G with 650Ω load when disabled. Analog Ground. Connect GA directly to a quiet ground node. Connect GA, GP12, and GP3 together at a single point as close to the IC as possible. Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. -4- www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 ABSOLUTE MAXIMUM RATINGSc PARAMETER VALUE UNIT VP1, VP2, SW1, SW2 to GP12 VP3, SW3 to GP3 SCL, SDA, INL, OUT1, OUT2, OUT3, OUT4, OUT5, OUT6, ON3, REFBP, nRSTO, PWRHLD, nMSTR to GA -0.3 to +6 V SW1 to VP1 SW2 to VP2 SW3 to VP3 -6 to +0.3 V -0.3 to +0.3 V Junction to Ambient Thermal Resistance (θJA) 30 °C/W RMS Power Dissipation (TA = 70°C) 1.8 W -40 to 85 °C Junction Temperature 125 °C Storage Temperature -55 to 150 °C 300 °C GP12, GP3 to GA Operating Temperature Range Lead Temperature (Soldering, 10 sec) c: Do not exceed these limits to prevent damage to the device. Exposure to absolute maximum rating conditions for long periods may affect device reliability. Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. -5- www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 SYSTEM MANAGEMENT REGISTER DESCRIPTIONS Table 1: Global Register Map OUTPUT ADDRESS DATA (DEFAULT VALUE) HEX A7 A6 A5 A4 A3 A2 A1 A0 D7 D6 D5 D4 D3 D2 D1 D0 REG1 10h 0 0 0 1 0 0 0 0 R V V V V V V V REG1 11h 0 0 0 1 0 0 0 1 R R R R R R R 0 REG1 12h 0 0 0 1 0 0 1 0 R R R R R R R R REG1 13h 0 0 0 1 0 0 1 1 R R R R R 0 R 1 REG2 20h 0 0 1 0 0 0 0 0 R V V V V V V V REG2 21h 0 0 1 0 0 0 0 1 R R R R R R R 0 REG2 22h 0 0 1 0 0 0 1 0 R R R R R R R R REG2 23h 0 0 1 0 0 0 1 1 R R R R R 0 R 1 REG3 30h 0 0 1 1 0 0 0 0 R V V V V V V V REG3 31h 0 0 1 1 0 0 0 1 R R R R R R R 0 REG3 32h 0 0 1 1 0 0 1 0 R R R R R R R R REG3 33h 0 0 1 1 0 0 1 1 R R R R R 0 R 1 REG4 03h 0 0 0 0 0 0 1 1 R V V V V V V V REG4 40h 0 1 0 0 0 0 0 0 R R 0 R R R R R REG5 41h 0 1 0 0 0 0 0 1 R R 0 V V V V V REG6 42h 0 1 0 0 0 0 1 0 R R 0 V V V V V REG456CFG 43h 0 1 0 0 0 0 1 1 R R R 1 1 1 0 R KEY: R: Read-Only bits. No Default Assigned. V: Default Values Depend on Voltage Option. Default Values May Vary. Note: Addresses other than those specified in Table 1 may be used for factory settings. Do not access any registers other than those specified in Table 1. Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. -6- www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 SYSTEM MANAGEMENT TYPICAL PERFORMANCE CHARACTERISTICS (VINL = 3.6V, TA = 25°C, unless otherwise specified.) Oscillator Frequency vs. Temperature ACT8798-001 1.71 Frequency (MHz) 1.68 1.65 1.62 1.59 1.56 1.53 1.50 -40 -20 0 20 40 60 85 Temperature (°C) Startup Sequence ACT8798-002 CH1 CH2 CH3 CH4 CH1: VnMSTR, 5V/div CH2: VnRSTO, 2V/div CH3: VPWRHLD, 5V/div CH4: VOUT1, 2V/div Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. TIME: 100ms/div -7- www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 SYSTEM MANAGEMENT ELECTRICAL CHARACTERISTICS (VINL = 3.6V, TA = 25°C, unless otherwise specified.) PARAMETER TEST CONDITIONS INL Operating Voltage Range TYP 2.6 INL UVLO Threshold INL Voltage Rising INL UVLO Hysteresis INL Voltage Falling Oscillator Frequency INL Supply Current MIN 2.25 UNIT 5.5 V 2.55 V 80 1.35 PWRHLD = ON3 = GA nMSTR Internal Pull-Up Resistance 2.4 MAX 250 1.6 mV 1.85 MHz 1.5 µA 500 kΩ Logic High Input Voltage PWRHLD, ON3, nMSTR Logic Low Input Voltage PWRHLD, ON3, nMSTR 0.4 V Logic Low Output Voltage ISINK = 5mA 0.3 V Leakage Current nRSTO, VnRSTO = 4.2V 1 µA 360 ms nRSTO Delay 1.4 240 V 300 Thermal Shutdown Temperature Temperature rising 160 °C Thermal Shutdown Hysteresis Temperature falling 20 °C Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. -8- www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 SYSTEM MANAGEMENT I2C INTERFACE ELECTRICAL CHARACTERISTICS (VINL = 3.6V, TA = 25°C, unless otherwise specified.) PARAMETER TEST CONDITIONS MIN SCL, SDA Low Input Voltage SCL, SDA High Input Voltage TYP MAX UNIT 0.4 V 1.4 SCL, SDA Leakage Current SDA Low Output Voltage IOL = 5mA SCL Clock Period, tSCL fSCL clock freq = 400kHz V 1 µA 0.3 V 2.5 µs SDA Data In Setup Time to SCL High, tSU 100 ns SDA Data Out Hold Time after SCL Low, tHD 300 ns SDA Data Low Setup Time to SCL Low, tST Start Condition 100 ns SDA Data High Hold Time after Clock High, tHP Stop Condition 100 ns Figure 1: I2C Serial Bus Timing Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. -9- www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 SYSTEM MANAGEMENT FUNCTIONAL DESCRIPTION General Description The ACT8798 offers an array of system management functions that allow it to provide optimal performance in a wide range of applications. I2C Serial Interface At the core of the ACT8798's flexible architecture is an I2C interface that permits optional programming capability to enhance overall system performance. To ensure compatibility with a wide range of system processors, the ACT8798 uses standard I2C commands; I2C write-byte commands are used to program the ACT8798, and I2C read-byte commands are used to read the ACT8798's internal registers. The ACT8798 always operates as a slave device, and is addressed using a 7-bit slave address followed by an eighth bit, which indicates whether the transaction is a read-operation or a write-operation, [1011011x]. SDA is a bi-directional data line and SCL is a clock input. The master initiates a transaction by issuing a START condition, defined by SDA transitioning from high to low while SCL is high. Data is transferred in 8-bit packets, beginning with the MSB, and is clocked-in on the rising edge of SCL. Each packet of data is followed by an Acknowledge (ACK) bit, used to confirm that the data was transmitted successfully. For more information regarding the I2C 2-wire serial interface, go to the NXP website: http://www.nxp.com System Startup and Shutdown The ACT8798 features a flexible control architecture that supports a variety of software-controlled enable/disable functions that make it a simple yet flexible and highly configurable solution. The ACT8798 is automatically enabled when either of the following conditions exists: 1) nMSTR is asserted low, or 2) PWRHLD is asserted high. If either of these conditions is true, the ACT8798 enables REG1, REG2, REG4, and may be REG3, powering up the system processor so that the startup and shutdown sequences may be controlled via software. These startup conditions are described in detail below. Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. Manual Enable Due to Asserting nMSTR Low System startup is initiated when the user presses the push-button, asserting nMSTR low. When this occurs, REG1, REG2, REG3, and REG4 are enabled and nRSTO is asserted low to hold the microprocessor in RESET for 260ms. nRSTO goes highZ upon expiration of the reset timer, de-asserting the processor's reset input and allowing the microprocessor to initiate its power up sequence. Once the power-up routine is successfully completed, the microprocessor must assert PWRHLD so that the ACT8798 remains enabled after the push-button is released by the user. Upon completion of the startup sequence the processor assumes control of the power system and all further operation is softwarecontrolled. Manual Enable Due to Asserting PWRHLD High The ACT8798 is compatible with applications that do not utilize its push-button control function, and may be enabled by simply driving PWRHLD to a logic-high to enable REG1, REG2, and REG4. In this case, the signal driving PWRHLD controls enable/disable timing, although software-controlled enable/disable sequences are still supported if the processor assumes control of the power system once the startup sequence is completed. Shutdown Sequence Once a successful power-up routine is completed, the system processor controls the operation of the power system, including the system shutdown timing and sequence. When using the application circuits shown in Figure 2, the nIRQ signal is asserted when nMSTR is asserted low, providing a simple means of alerting the system processor when the user wishes to shut the system down. Asserting nIRQ interrupts the system processor, initiating an interrupt service routine in the processor which will reveal that the user pressed the push-button. The microprocessor may validate the input, such as by ensuring that the push-button is asserted for a minimum amount of time, then initiates a software controlled power-down routine, the final step of which is to de-assert the PWRHLD input, disabling the regulators and shutting the system down. - 10 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 SYSTEM MANAGEMENT FUNCTIONAL DESCRIPTION (CONT’D) nMSTR Enable Input nIRQ Output In most applications, connect nMSTR to an active low, momentary push-button switch to utilize the ACT8798's closed-loop enable/disable functionality. If a momentary-on switch is not used, drive nMSTR to GA or to a logic low to initiate a startup sequence. Figure 2 shows two simple circuits that can be used to generate nIRQ, a processor interrupt signal, which can be used as part of the ACT8798’s pushbutton control logic. This signal is typically used to drive the interrupt input of the system processor, and is useful in a variety of software-controlled enable/disable control routines. Figure 2A provides an active-low, open-collector push-button status output that sinks current when nMSTR is driven to a logiclow. Figure 2B provides an active-high, opencollector push-button status output that sources current when nMSTR is driven to a logic-low. Enable/Disable Inputs The ACT8798 provides two manual enable/disable inputs, PWRHLD and ON3. PWRHLD is the master enable input. When driven high, PWRHLD enables REG1, REG2, and REG4, and also activates the enable/disable control logic for the other regulators. ON3 is the enable input for REG3, and is active when either of the following conditions exists: 1) nMSTR is asserted low, or 2) PWRHLD is asserted high. Power-On Reset Output The ACT8798 integrates a 260ms power-on reset generator, reducing system size and cost. nRSTO is an open-drain output. Connect a 10kΩ or greater pull-up resistor from nRSTO to an appropriate voltage supply. nRSTO asserts low upon startup and remains low until the reset-timeout period expires, at which point nRSTO goes high-Z. Thermal Shutdown The ACT8798 integrates thermal shutdown protection circuitry to prevent damage resulting from excessive thermal stress, as may be encountered under fault conditions. This circuitry disables all regulators if the ACT8798 die temperature exceeds 160°C, and prevents the regulators from being enabled until the IC temperature drops by 20°C (typ). Figure 2: Simple Circuits OUT2 VCC 100k nMSTR INL 100k 500k ACT8798 OUT2 PB VCC 100k nIRQ PB CPU nIRQ ACT8798 100k (A) Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. (B) - 11 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 STEP-DOWN DC/DC CONVERTERS ELECTRICAL CHARACTERISTICS (REG1) (VVP1 = 3.6V, TA = 25°C, unless otherwise specified.) PARAMETER TEST CONDITIONS VP1 Operating Voltage Range MIN 3.1 VP1 UVLO Threshold Input Voltage Rising VP1 UVLO Hysteresis Input Voltage Falling 2.9 Output Voltage Regulation Accuracy REG1 is disabled, VVP1 = 4.2V UNIT 5.5 V 3.1 V mV 130 200 µA 0.1 1 µA VNOM1 < 1.3V, IOUT1 = 10mA -2.4% VNOM1c +1.8% VNOM1 ≥ 1.3V, IOUT1 = 10mA -1.2% VNOM1 +1.8% Line Regulation VVP1 = Max(VNOM1 + 1V, 3.2V) to 5.5V Load Regulation IOUT1 = 10mA to 1.2A Current Limit Oscillator Frequency 3 MAX 80 Standby Supply Current Shutdown Supply Current TYP 0.15 %/V 0.0017 %/mA 1.2 VOUT1 ≥ 20% of VNOM1 1.35 V A 1.6 1.85 MHz VOUT1 = 0V 530 PMOS On-Resistance ISW1 = -100mA 0.28 0.50 Ω NMOS On-Resistance ISW1 = 100mA 0.20 0.35 Ω SW1 Leakage Current VVP1 = 5.5V, VSW1 = 5.5V or 0V 1 µA kHz Power Good Threshold 94 %VNOM1 Minimum On-Time 70 ns c: VNOM1 refers to the nominal output voltage level for VOUT1 as defined by the Ordering Information section. Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 12 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 STEP-DOWN DC/DC CONVERTERS REGISTER DESCRIPTIONS Note: See Table 1 for default register settings. Table 2: REG1 Control Register Map ADDRESS DATA D7 D6 D5 D4 10h R VRANGE 11h R R R R 12h R R R 13h R R R D3 D2 D1 D0 R R R MODE R R R R R R R W/E OK ON VSET R: Read-Only bits. Default Values May Vary. W/E: Write-Exact bits. Read/Write bits which must be written exactly as specified in Table 1 Table 3: REG1 Control Register Bit Descriptions ADDRESS NAME BIT ACCESS FUNCTION DESCRIPTION 10h VSET [5:0] R/W REG1 Output Voltage Selection See Table 4 10h VRANGE [6] R/W REG1 Voltage Range Selection [7] R [0] R/W 11h [7:1] R READ ONLY 12h [7:0] R READ ONLY 10h 11h MODE 0 Min VOUT = 1.1V 1 Min VOUT = 1.25V READ ONLY Mode Selection 0 PWM/PFM 1 Forced PWM 0 REG1 Disable 1 REG1 Enable 0 Output is not OK 1 Output is OK 13h ON [0] R/W REG1 Enable 13h OK [1] R REG1 Power-OK 13h [2] W/E WRITE-EXACT 13h [7:3] R READ ONLY Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 13 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 STEP-DOWN DC/DC CONVERTERS REGISTER DESCRIPTIONS CONT’D Table 4: REG1/VSET[ ] Output Voltage Setting REG1/VSET[5:4] REG1/VSET[3:0] REG1/VRANGE[ ] = [0] REG1/VRANGE[ ] = [1] 00 01 10 11 00 01 10 11 0000 N/A N/A 1.455 1.860 1.250 2.050 2.850 3.650 0001 N/A N/A 1.480 1.890 1.300 2.100 2.900 3.700 0010 N/A 1.100 1.505 1.915 1.350 2.150 2.950 3.750 0011 N/A 1.125 1.530 1.940 1.400 2.200 3.000 3.800 0100 N/A 1.150 1.555 1.965 1.450 2.250 3.050 3.850 0101 N/A 1.175 1.585 1.990 1.500 2.300 3.100 3.900 0110 N/A 1.200 1.610 2.015 1.550 2.350 3.150 3.950 0111 N/A 1.225 1.635 2.040 1.600 2.400 3.200 4.000 1000 N/A 1.255 1.660 2.065 1.650 2.450 3.250 4.050 1001 N/A 1.280 1.685 2.090 1.700 2.500 3.300 4.100 1010 N/A 1.305 1.710 2.115 1.750 2.550 3.350 4.150 1011 N/A 1.330 1.735 2.140 1.800 2.600 3.400 4.200 1100 N/A 1.355 1.760 2.165 1.850 2.650 3.450 4.250 1101 N/A 1.380 1.785 2.190 1.900 2.700 3.500 4.300 1110 N/A 1.405 1.810 2.200 1.950 2.750 3.550 4.350 1111 N/A 1.430 1.835 2.245 2.000 2.800 3.600 4.400 (N/A): Not Available Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 14 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 STEP-DOWN DC/DC CONVERTERS ELECTRICAL CHARACTERISTICS (REG2) (VVP2 = 3.6V, TA = 25°C, unless otherwise specified.) PARAMETER TEST CONDITIONS VP2 Operating Voltage Range MIN 3.1 VP2 UVLO Threshold Input Voltage Rising VP2 UVLO Hysteresis Input Voltage Falling 2.9 Output Voltage Regulation Accuracy REG2 Disabled, VVP2 = 4.2V 0.1 c VNOM2 < 1.3V, IOUT2 = 10mA -2.4% VNOM2 VNOM2 ≥ 1.3V, IOUT2 = 10mA -1.2% VNOM2 VVP2 = Max(VNOM2 + 1V, 3.2V) to 5.5V Load Regulation IOUT2 = 10mA to 1.2A Current Limit UNIT 5.5 V 3.1 V mV 130 Line Regulation Oscillator Frequency 3 MAX 80 Standby Supply Current Shutdown Supply Current TYP 200 µA 1 µA +1.8% +1.8% 0.15 %/V 0.0017 %/mA 1.2 VOUT2 ≥ 20% of VNOM2 1.35 V A 1.6 1.85 MHz VOUT2 = 0V 530 PMOS On-Resistance ISW2 = -100mA 0.28 0.50 Ω NMOS On-Resistance ISW2 = 100mA 0.20 0.35 Ω SW2 Leakage Current VVP2 = 5.5V, VSW2 = 5.5V or 0V 1 µA kHz Power Good Threshold 94 %VNOM2 Minimum On-Time 70 ns c: VNOM2 refers to the nominal output voltage level for VOUT2 as defined by the Ordering Information section. Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 15 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 STEP-DOWN DC/DC CONVERTERS REGISTER DESCRIPTIONS Note: See Table 1 for default register settings. Table 5: REG2 Control Register Map ADDRESS DATA D7 D6 D5 D4 20h R VRANGE 21h R R R R 22h R R R 23h R R R D3 D2 D1 D0 R R R MODE R R R R R R R W/E OK ON VSET R: Read-Only bits. Default Values May Vary. W/E: Write-Exact bits. Read/Write bits which must be written exactly as specified in Table 1 Table 6: REG2 Control Register Bit Descriptions ADDRESS NAME BIT ACCESS FUNCTION DESCRIPTION 20h VSET [5:0] R/W REG2 Output Voltage Selection See Table 7 20h VRANGE [6] R/W REG2 Voltage Range Selection [7] R [0] R/W 21h [7:1] R READ ONLY 22h [7:0] R READ ONLY 20h 21h MODE 0 Min VOUT = 1.1V 1 Min VOUT = 1.25V READ ONLY Mode Selection 0 PWM/PFM 1 Forced PWM 0 REG2 Disable 1 REG2 Enable 0 Output is not OK 1 Output is OK 23h ON [0] R/W REG2 Enable 23h OK [1] R REG2 Power-OK 23h [2] W/E WRITE-EXACT 23h [7:3] R READ ONLY Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 16 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 STEP-DOWN DC/DC CONVERTERS REGISTER DESCRIPTIONS CONT’D Table 7: REG2/VSET[ ] Output Voltage Setting REG2/VSET[5:4] REG2/VSET[3:0] REG2/VRANGE[ ] = [0] REG2/VRANGE[ ] = [1] 00 01 10 11 00 01 10 11 0000 N/A N/A 1.455 1.860 1.250 2.050 2.850 3.650 0001 N/A N/A 1.480 1.890 1.300 2.100 2.900 3.700 0010 N/A 1.100 1.505 1.915 1.350 2.150 2.950 3.750 0011 N/A 1.125 1.530 1.940 1.400 2.200 3.000 3.800 0100 N/A 1.150 1.555 1.965 1.450 2.250 3.050 3.850 0101 N/A 1.175 1.585 1.990 1.500 2.300 3.100 3.900 0110 N/A 1.200 1.610 2.015 1.550 2.350 3.150 3.950 0111 N/A 1.225 1.635 2.040 1.600 2.400 3.200 4.000 1000 N/A 1.255 1.660 2.065 1.650 2.450 3.250 4.050 1001 N/A 1.280 1.685 2.090 1.700 2.500 3.300 4.100 1010 N/A 1.305 1.710 2.115 1.750 2.550 3.350 4.150 1011 N/A 1.330 1.735 2.140 1.800 2.600 3.400 4.200 1100 N/A 1.355 1.760 2.165 1.850 2.650 3.450 4.250 1101 N/A 1.380 1.785 2.190 1.900 2.700 3.500 4.300 1110 N/A 1.405 1.810 2.200 1.950 2.750 3.550 4.350 1111 N/A 1.430 1.835 2.245 2.000 2.800 3.600 4.400 (N/A): Not Available Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 17 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 STEP-DOWN DC/DC CONVERTERS ELECTRICAL CHARACTERISTICS (REG3) (VVP3 = 3.6V, TA = 25°C, unless otherwise specified.) PARAMETER TEST CONDITIONS VP3 Operating Voltage Range MIN 3.1 VP3 UVLO Threshold Input Voltage Rising VP3 UVLO Hysteresis Input Voltage Falling 2.9 Output Voltage Regulation Accuracy REG3 Disabled, VVP3 = 4.2V 0.1 c VNOM3 < 1.3V, IOUT3 = 10mA -2.4% VNOM3 VNOM3 ≥ 1.3V, IOUT3 = 10mA -1.2% VNOM3 VVP3 = Max(VNOM3 + 1V, 3.2V) to 5.5V Load Regulation IOUT3 = 10mA to 750mA Current Limit VOUT3 ≥ 20% of VNOM3 UNIT 5.5 V 3.1 V mV 130 Line Regulation Oscillator Frequency 3 MAX 80 Standby Supply Current Shutdown Supply Current TYP 200 µA 1 µA +1.8% +1.8% V 0.15 %/V 0.0017 %/mA 0.85 1.1 A 1.35 1.6 1.85 MHz VOUT3 = 0V 530 PMOS On-Resistance ISW3 = -100mA 0.28 0.50 Ω NMOS On-Resistance ISW3 = 100mA 0.20 0.35 Ω SW3 Leakage Current VVP3 = 5.5V, VSW3 = 5.5V or 0V 1 µA kHz Power Good Threshold 94 %VNOM3 Minimum On-Time 70 ns c: VNOM3 refers to the nominal output voltage level for VOUT3 as defined by the Ordering Information section. Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 18 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 STEP-DOWN DC/DC CONVERTERS REGISTER DESCRIPTIONS Note: See Table 1 for default register settings. Table 8: REG3 Control Register Map ADDRESS DATA D7 D6 D5 D4 30h R VRANGE 31h R R R R 32h R R R 33h R R R D3 D2 D1 D0 R R R MODE R R R R R R R W/E OK ON VSET R: Read-Only bits. Default Values May Vary. W/E: Write-Exact bits. Read/Write bits which must be written exactly as specified in Table 1 Table 9: REG3 Control Register Bit Descriptions ADDRESS NAME BIT ACCESS FUNCTION DESCRIPTION 30h VSET [5:0] R/W REG3 Output Voltage Selection See Table 10 30h VRANGE [6] R/W REG3 Voltage Range Selection [7] R [0] R/W 31h [7:1] R READ ONLY 32h [7:0] R READ ONLY 30h 31h MODE 0 Min VOUT = 1.1V 1 Min VOUT = 1.25V READ ONLY Mode Selection 0 PWM/PFM 1 Forced PWM 0 REG3 Disable 1 REG3 Enable 0 Output is not OK 1 Output is OK 33h ON [0] R/W REG3 Enable 33h OK [1] R REG3 Power-OK 33h [2] W/E WRITE-EXACT 33h [7:3] R READ ONLY Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 19 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 STEP-DOWN DC/DC CONVERTERS REGISTER DESCRIPTIONS CONT’D Table 10: REG3/VSET[ ] Output Voltage Setting REG3/VSET[5:4] REG3/VSET[3:0] REG3/VRANGE[ ] = [0] REG3/VRANGE[ ] = [1] 00 01 10 11 00 01 10 11 0000 N/A N/A 1.455 1.860 1.250 2.050 2.850 3.650 0001 N/A N/A 1.480 1.890 1.300 2.100 2.900 3.700 0010 N/A 1.100 1.505 1.915 1.350 2.150 2.950 3.750 0011 N/A 1.125 1.530 1.940 1.400 2.200 3.000 3.800 0100 N/A 1.150 1.555 1.965 1.450 2.250 3.050 3.850 0101 N/A 1.175 1.585 1.990 1.500 2.300 3.100 3.900 0110 N/A 1.200 1.610 2.015 1.550 2.350 3.150 3.950 0111 N/A 1.225 1.635 2.040 1.600 2.400 3.200 4.000 1000 N/A 1.255 1.660 2.065 1.650 2.450 3.250 4.050 1001 N/A 1.280 1.685 2.090 1.700 2.500 3.300 4.100 1010 N/A 1.305 1.710 2.115 1.750 2.550 3.350 4.150 1011 N/A 1.330 1.735 2.140 1.800 2.600 3.400 4.200 1100 N/A 1.355 1.760 2.165 1.850 2.650 3.450 4.250 1101 N/A 1.380 1.785 2.190 1.900 2.700 3.500 4.300 1110 N/A 1.405 1.810 2.200 1.950 2.750 3.550 4.350 1111 N/A 1.430 1.835 2.245 2.000 2.800 3.600 4.400 (N/A): Not Available Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 20 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 STEP-DOWN DC/DC CONVERTERS TYPICAL PERFORMANCE CHARACTERISTICS (ACT8798QLGHW, VVP1 = VVP2 = 3.6V, L = 3.3µH, CVP1 = CVP2 = 2.2µF, COUT1 = COUT2 = 10µF, TA = 25°C, unless otherwise specified.) REG1 Efficiency vs. Load Current Efficiency (%) 90 4.2V 85 95 4.2V 90 Efficiency (%) 3.6V 95 80 75 80 75 70 65 65 60 3.6V 85 70 60 1 10 1 1000 100 10 Output Current (mA) 0.181 OUT2 Voltage Accuracy (%) 0.363 0.000 -0.181 -0.363 ACT8798-006 0.545 ACT8798-005 OUT1 Voltage Accuracy (%) 1000 OUT2 Regulation Voltage IOUT1 = 35mA -0.545 IOUT2 = 35mA 0.363 0.181 0.000 -0.181 -0.363 -0.545 -40 -20 0 20 40 60 85 -40 -20 0 20 40 60 Temperature (°C) Temperature (°C) REG1 MOSFET Resistance REG2 MOSFET Resistance 400 400 PMOS RDSON (mΩ) PMOS 300 NMOS 200 85 ACT8798-008 500 ACT8798-007 500 RDSON (mΩ) 100 Output Current (mA) OUT1 Regulation Voltage 0.545 ACT8798-004 VOUT1 = 1.2V REG2 Efficiency vs. Load Current 100 V OUT2 = 2.8V ACT8798-003 100 300 NMOS 200 100 100 0 0 3 3.5 4.0 4.5 5.0 3 5.5 ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. 4.0 4.5 5.0 5.5 VP2 Voltage (V) VP1 Voltage (V) Innovative PowerTM 3.5 - 21 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 STEP-DOWN DC/DC CONVERTERS TYPICAL PERFORMANCE CHARACTERISTICS (ACT8798QLGHW, VVP1 = VVP2 = VVP3 = 3.6V, L = 3.3µH, CVP1 = CVP2 = CVP3 = 2.2µF, COUT1 = COUT2 = COUT3 = 10µF, TA = 25°C, unless otherwise specified.) REG3 Efficiency vs. Load Current ACT8798-009 95 VOUT3 = 1.8V 3.6V 90 Efficiency (%) 85 4.2V 80 75 70 60 65 55 50 10 1 100 1000 Output Current (mA) OUT3 Regulation Voltage OUT1 Voltage Accuracy (%) ACT8798-010 0.666 IOUT3 = 35mA 0.444 0.222 0.0 -0.222 -0.444 -0.666 -40 -20 0 20 40 60 85 Temperature (°C) REG3 MOSFET Resistance 450 400 PMOS RDSON (mΩ) 350 ACT8798-011 500 300 250 NMOS 200 150 100 50 0 3 3.5 4.0 4.5 5.0 5.5 VP3 Voltage (V) Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 22 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 STEP-DOWN DC/DC CONVERTERS FUNCTIONAL DESCRIPTION General Description Programming the Output Voltage REG1, REG2, and REG3 are fixed-frequency, current-mode, synchronous PWM step down converters that achieve peak efficiencies of up to 97%. REG1 and REG2 are capable of supplying up to 1.2A of output current, while REG3 supports up to 750mA. These regulators operate with a fixed frequency of 1.6MHz, minimizing noise in sensitive applications and allowing the use of small external components. Each of the step-down DC/DCs are available with a variety of standard and custom output voltages, and each may be software-controlled via the I2C interface by systems that require advanced power management functions. By default, REG1, REG2, and REG3 each power up and regulate to their default output voltage. Once the system is enabled, each regulator's output voltage may be independently programmed to a different value, typically in order to reduce the power consumption of a microprocessor in standby mode. Program the output voltages via the I2C serial interface by writing to the REGx/VSETx[ ] and REGx/VRANGE[ ] registers. 100% Duty Cycle Operation REG1, REG2, and REG3 are each capable of operating at up to 100% duty cycle. During 100% dutycycle operation, the high-side power MOSFET is held on continuously, providing a direct connection from the input to the output (through the inductor), ensuring the lowest possible dropout voltage in battery powered applications. Synchronous Rectification REG1, REG2, and REG3 each feature integrated nchannel synchronous rectifiers, maximizing efficiency and minimizing the total solution size and cost by eliminating the need for external rectifiers. Enabling and Disabling REG1, REG2, and REG3 Enable/disable functionality is typically implemented as part of a controlled enable/disable scheme utilizing nMSTR and other system control features of the ACT8798. REG1 and REG2 are automatically enabled whenever either of the following conditions re met: 1) nMSTR is driven low, or 2) PWRHLD is asserted high. When none of these conditions are true, or if a regulator’s ON[_] bit is set to [0], REG1 and REG2 are disabled, and each regulator’s quiescent supply current drops to less than 1µA. REG3 is enabled whenever ON3 is asserted high, and is disabled whenever ON is asserted low or if the REG3/ON[_] bit is set to [0]. Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. Programmable Operating Mode By default, REG1, REG2, and REG3 each operate in fixed-frequency PWM mode at medium to heavy loads, then transition to a proprietary power-saving mode at light loads in order to save power. In applications where low noise is critical, force fixedfrequency PWM operation across the entire load current range, at the expense of light-load efficiency, by setting the REGx/MODE[ ] bit to [1]. Power-OK REG1, REG2, and REG3 each feature a variety of status bits that can be read by the system microprocessor. If either output voltage is lower than the power-OK threshold, typically 6% below the programmed regulation voltage, REGx/OK[ ] will clear to 0. Soft-Start REG1, REG2, and REG3 each include matched soft-start circuitry. When enabled, the output voltages track the internal 80µs soft-start ramp and both power up in a monotonic manner that is independent of loading on either output. This circuitry ensures that each output powers up in a controlled manner, greatly simplifying power sequencing design considerations. Compensation REG1, REG2, and REG3 utilize current-mode control and a proprietary internal compensation scheme to simultaneously simplify external component selection and optimize transient performance over their full operating range. No compensation design is required; simply follow a few simple guidelines described below when choosing external components. - 23 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 STEP-DOWN DC/DC CONVERTERS FUNCTIONAL DESCRIPTION (CONT’D) Input Capacitor Selection The input capacitor reduces peak currents and noise induced upon the voltage source. A 2.2µF ceramic capacitor for each of REG1, REG2, and REG3 is recommended for most applications. sufficient distance from switching nodes to prevent noise injection. Finally, the exposed pad should be directly connected to the backside ground plane using multiple via to achieve low electrical and thermal resistance. Output Capacitor Selection For most applications, 10µF ceramic output capacitors are recommended for REG1, REG2, and REG3. Although the these regulators were designed to take advantage of the benefits of ceramic capacitors, namely small size and very-low ESR, low-ESR tantalum capacitors can provide acceptable results as well. Inductor Selection REG1, REG2, and REG3 utilize current-mode control and a proprietary internal compensation scheme to simultaneously simplify external component selection and optimize transient performance over their full operating range. These devices were optimized for operation with 3.3µH inductors, although inductors in the 2.2µH to 4.7µH range can be used. Choose an inductor with a low DCresistance, and avoid inductor saturation by choosing inductors with DC ratings that exceed the maximum output current of the application by at least 30%. PCB Layout Considerations High switching frequencies and large peak currents make PC board layout an important part of stepdown DC/DC converter design. A good design minimizes excessive EMI on the feedback paths and voltage gradients in the ground plane, both of which can result in instability or regulation errors. Stepdown DC/DCs exhibit discontinuous input current, so the input capacitors should be placed as close as possible to the IC, and avoiding the use of via if possible. The inductor, input filter capacitor, and output filter capacitor should be connected as close together as possible, with short, direct, and wide traces. The ground nodes for each regulator's power loop should be connected at a single point in a star-ground configuration, and this point should be connected to the backside ground plane with multiple via. The output node for each regulator should be connected to its corresponding OUTx pin through the shortest possible route, while keeping Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 24 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 LOW-DROPOUT LINEAR REGULATORS ELECTRICAL CHARACTERISTICS (REG4) (VINL = 3.6V, COUT4 = 1µF, TA = 25°C, unless otherwise specified.) PARAMETER TEST CONDITIONS INL Operating Voltage Range VINL Input Rising UVLO Hysteresis VINL Input Falling 2.9 V 3.1 V V VNOM4c +1.8% VNOM4 ≥ 1.3V, IOUT4 = 10mA -1.2% VNOM4 +1.8% IOUT4 = 1mA to 250mA mV -0.004 %/mA f = 1kHz, IOUT4 = 250mA, COUT4 = 1µF 60 f = 10kHz, IOUT4 = 250mA, COUT4 = 1µF 50 Regulator Enabled 40 Regulator Disabled 0 IOUT4 = 120mA, VOUT4 > 3.1V 100 dB µA 200 250 VOUT4 = 95% of regulation voltage 280 Internal Soft-Start V 0 Output Current Current Limit3 5.5 -2.4% Load Regulation Error Dropout Voltaged UNIT VNOM4 < 1.3V, IOUT4 = 10mA VINL = Max(VOUT4 + 0.5V, 3.6V) to 5.5V Supply Current per Output 3 MAX 0.1 Line Regulation Error Power Supply Rejection Ratio TYP 3.1 INL UVLO Threshold Output Voltage Accuracy MIN mV mA 100 µs Power Good Flag High Threshold VOUT4, hysteresis = -4% 89 % Output Noise COUT4 = 10µF, f = 10Hz to 100kHz 40 µVRMS Stable COUT4 Range Discharge Resistor in Shutdown 1 LDO Disabled, DIS4[ ] = [1] 20 650 µF Ω c: VNOM4 refers to the nominal output voltage level for VOUT4 as defined by the Ordering Information section. d: Dropout Voltage is defined as the differential voltage between input and output when the output voltage drops 100mV below the regulation voltage at 1V differential voltage (for 2.8V output voltage or higher) 3: LDO current limit is defined as the output current at which the output voltage drops to 95% of the respective regulation voltage. Under heavy overload conditions the output current limit folds back by 30% (typ) Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 25 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 LOW-DROPOUT LINEAR REGULATORS ELECTRICAL CHARACTERISTICS (REG5) (VINL = 3.6V, COUT5 = 1µF, TA = 25°C, unless otherwise specified.) PARAMETER TEST CONDITIONS INL Operating Voltage Range VINL Input Rising UVLO Hysteresis VINL Input Falling 2.9 3.1 V V +2 TA = -40°C to 85°C -2.5 VNOM5 +3 mV -0.004 %/mA f = 1kHz, IOUT5 = 250mA, COUT5 = 1µF 70 f = 10kHz, IOUT5 = 250mA, COUT5 = 1µF 60 Regulator Enabled 40 Regulator Disabled 0 IOUT5 = 120mA, VOUT5 > 3.1V VOUT5 = 95% of regulation voltage 100 dB µA 200 mV 250 mA 280 Internal Soft-Start % 0 Output Current Current Limit V VNOM5c IOUT5 = 1mA to 250mA 3 5.5 -1.2 Load Regulation Error Dropout Voltaged UNIT TA = 25°C VINL = Max(VOUT5 + 0.5V, 3.6V) to 5.5V Supply Current per Output 3 MAX 0.1 Line Regulation Error Power Supply Rejection Ratio TYP 3.1 INL UVLO Threshold Output Voltage Accuracy MIN mA 100 µs Power Good Flag High Threshold VOUT5, hysteresis = -4% 89 % Output Noise COUT5 = 10µF, f = 10Hz to 100kHz 40 µVRMS Stable COUT5 Range Discharge Resistor in Shutdown 1 LDO Disabled, DIS5[ ] = [1] 20 650 µF Ω c: VNOM5 refers to the nominal output voltage level for VOUT5 as defined by the Ordering Information section. d: Dropout Voltage is defined as the differential voltage between input and output when the output voltage drops 100mV below the regulation voltage at 1V differential voltage (for 2.8V output voltage or higher) 3: LDO current limit is defined as the output current at which the output voltage drops to 95% of the respective regulation voltage. Under heavy overload conditions the output current limit folds back by 30% (typ) Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 26 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 LOW-DROPOUT LINEAR REGULATORS ELECTRICAL CHARACTERISTICS (REG6) (VINL = 3.6V, COUT6 = 1µF, TA = 25°C, unless otherwise specified.) PARAMETER TEST CONDITIONS INL Operating Voltage Range VINL Input Rising UVLO Hysteresis VINL Input Falling 2.9 V 3.1 V V VNOM6c +2 TA = -40°C to 85°C -2.5 VNOM6 +3 IOUT6 = 1mA to 250mA mV -0.004 %/mA f = 1kHz, IOUT6 = 250mA, COUT6 = 1µF 70 f = 10kHz, IOUT6 = 250mA, COUT6 = 1µF 60 Regulator Enabled 40 Regulator Disabled 0 IOUT6 = 120mA, VOUT6 > 3.1V VOUT6 = 95% of regulation voltage % 0 dB µA 100 Output Current Current Limit3 5.5 -1.2 Load Regulation Error Dropout Voltaged UNIT TA = 25°C VINL = Max(VOUT6 + 0.5V, 3.6V) to 5.5V Supply Current per Output 3 MAX 0.1 Line Regulation Error Power Supply Rejection Ratio TYP 3.1 INL UVLO Threshold Output Voltage Accuracy MIN 200 mV 250 mA 280 Internal Soft-Start mA 100 µs Power Good Flag High Threshold VOUT6, hysteresis = -4% 89 % Output Noise COUT6 = 10µF, f = 10Hz to 100kHz 40 µVRMS Stable COUT6 Range Discharge Resistor in Shutdown 1 LDO Disabled, DIS6[ ] = [1] 20 650 µF Ω c: VNOM6 refers to the nominal output voltage level for VOUT6 as defined by the Ordering Information section. d: Dropout Voltage is defined as the differential voltage between input and output when the output voltage drops 100mV below the regulation voltage at 1V differential voltage (for 2.8V output voltage or higher) 3: LDO current limit is defined as the output current at which the output voltage drops to 95% of the respective regulation voltage. Under heavy overload conditions the output current limit folds back by 30% (typ) Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 27 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 LOW-DROPOUT LINEAR REGULATORS REGISTER DESCRIPTIONS Note: See Table 1 for default register settings. Table 11: Control Register Map DATA ADDRESS D7 D6 D5 D4 D3 D2 D1 D0 03h R VRANGE 40h R R W/E R R R 41h R R ON5 VSET5 42h R R ON6 VSET6 43h OK6 OK5 OK4 W/E R VSET4 R DIS6 R DIS5 DIS4 R: Read-Only bits. Default Values May Vary. W/E: Write-Exact bits. Read/Write bits which must be written exactly as specified in Table 1. Table 12: REG56 Control Register Bit Descriptions ADDRESS NAME BIT ACCESS FUNCTION DESCRIPTION 03h VSET4 [5:0] R/W REG4 Output Voltage Selection See Table 14 03h VRANGE [6] R/W REG4 Output Voltage Selection 03h [7] R READ ONLY 40h [4:0] R READ ONLY 40h [5] W/E WRITE-EXACT 40h [7:6] R READ ONLY 41h VSET5 [4:0] R/W REG5 Output Voltage Selection 41h ON5 [5] R/W REG5 Enable [7:6] R 41h 0 Min VOUT = 0.645V 1 Min VOUT = 1.25V See Table 13 0 REG5 Disable 1 REG5 Enable READ ONLY 42h VSET6 [4:0] R/W REG6 Output Voltage Selection 42h ON6 [5] R/W REG6 Enable 42h [7:6] R READ ONLY 43h [0] R READ ONLY 43h [1] W/E WRITE-EXACT Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 28 - See Table 13 0 REG6 Disable 1 REG6 Enable www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 LOW-DROPOUT LINEAR REGULATORS REGISTER DESCRIPTIONS CONT’D Table 12: Control Register Bit Descriptions (Cont’d) ADDRESS NAME BIT ACCESS FUNCTION 43h DIS4 [2] R/W REG4 Discharge Enable 43h DIS5 [3] R/W REG5 Discharge Enable 43h DIS6 [4] R/W REG6 Discharge Enable 43h OK4 [5] R REG4 Power-OK 43h OK5 [6] R REG5 Power-OK 43h OK6 [7] R REG6 Power-OK DESCRIPTION 0 Discharge Disable 1 Discharge Enable 0 Discharge Disable 1 Discharge Enable 0 Discharge Disable 1 Discharge Enable 0 Output is not OK 1 Output is OK 0 Output is not OK 1 Output is OK 0 Output is not OK 1 Output is OK Table 13: REG56/VSETx[ ] Output Voltage Setting REG56CFG/VSETx[2:0] REG56CFG/VSETx[4:3] 00 01 10 11 000 1.4 2.15 2.55 3.0 001 1.5 2.20 2.60 3.1 010 1.6 2.25 2.65 3.2 011 1.7 2.30 2.70 3.3 100 1.8 2.35 2.75 3.4 101 1.9 2.40 2.80 3.5 110 2.0 2.45 2.85 3.6 111 2.1 2.50 2.90 3.7 Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 29 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 LOW-DROPOUT LINEAR REGULATORS REGISTER DESCRIPTIONS CONT’D Table 14: REG4/VRANGE[ ] Output Voltage Setting REG4/VSET[5:4] REG4/VSET[3:0] REG4/VRANGE[ ] = [0] REG4/VRANGE[ ] = [1] 00 01 10 11 00 01 10 11 0000 0.645 1.050 1.455 1.860 1.250 2.050 2.850 3.650 0001 0.670 1.075 1.480 1.890 1.300 2.100 2.900 3.700 0010 0.695 1.100 1.505 1.915 1.350 2.150 2.950 N/A 0011 0.720 1.125 1.530 1.940 1.400 2.200 3.000 N/A 0100 0.745 1.150 1.555 1.965 1.450 2.250 3.050 N/A 0101 0.770 1.175 1.585 1.990 1.500 2.300 3.100 N/A 0110 0.795 1.200 1.610 2.015 1.550 2.350 3.150 N/A 0111 0.820 1.225 1.635 2.040 1.600 2.400 3.200 N/A 1000 0.845 1.255 1.660 2.065 1.650 2.450 3.250 N/A 1001 0.870 1.280 1.685 2.090 1.700 2.500 3.300 N/A 1010 0.895 1.305 1.710 2.115 1.750 2.550 3.350 N/A 1011 0.920 1.330 1.735 2.140 1.800 2.600 3.400 N/A 1100 0.950 1.355 1.760 2.165 1.850 2.650 3.450 N/A 1101 0.975 1.380 1.785 2.190 1.900 2.700 3.500 N/A 1110 1.000 1.405 1.810 2.200 1.950 2.750 3.550 N/A 1111 1.025 1.430 1.835 2.245 2.000 2.800 3.600 N/A (N/A): Not Available Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 30 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 LOW-DROPOUT LINEAR REGULATORS TYPICAL PERFORMANCE CHARACTERISTICS (ACT8798QLGHW, VVIN = 5V, TA = 25°C, unless otherwise specified.) Dropout Voltage vs. Output Current Load Regulation 0.3 0.2 180 Dropout Voltage (mV) Output Voltage (V) 0.4 0.1 0.0 -0.1 -0.2 -0.3 -0.4 140 100 60 40 0 25 50 75 100 125 150 175 200 225 250 0 50 100 150 200 Load Current (mA) Output Current (mA) Output Voltage Deviation vs. Temperature LDO Output Voltage Noise ILOAD = 0mA 0.3 0.2 250 ACT8798-016 ACT8798-015 Output Voltage Deviation (%) VIN = 3.6V 80 20 0 0.4 VIN = 3.3V 120 -0.5 0.5 VIN = 3.1V 160 ACT8798-014 200 ACT8798-013 0.5 0.1 CH1 0.0 -0.1 -0.2 -0.3 CREF = 10nF -0.4 -0.5 -40 -15 10 35 60 85 CH1: VOUTx, 200µV/div (AC COUPLED) TIME: 200ms/div Temperature (°C) Region of Stable COUT ESR vs. Output Current ESR (Ω) ACT8798-017 1 0.1 Stable ESR 0.01 0 50 100 150 200 250 Output Current (mA) Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 31 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 LOW-DROPOUT LINEAR REGULATORS FUNCTIONAL DESCRIPTION General Description Power-OK REG4, REG5, and REG6 are low-noise, lowdropout linear regulators (LDOs) that are optimized for low noise and high-PSRR operation, achieving more than 60dB PSRR at frequencies up to 10kHz. Each of the LDOs features power-OK status bit that can be read by the system microprocessor via the I2C interface. If an output voltage is lower than the power-OK threshold, typically 15% below the programmed regulation voltage, the corresponding REG456CFG/OKx[ ] will clear to 0. LDO Output Voltage Programming All LDOs feature independently-programmable output voltages that are set via the I2C serial interface, increasing the ACT8798’s flexibility while reducing total solution size and cost. Set the output voltage by writing to the REG456CFG/VSETx[ ] registers. Reference Bypass Pin Output Current Capability Optional LDO Output Discharge REG4, REG5, and REG6 each supply an output current of 250mA. Excellent performance is achieved over this load current range. Output Current Limit In order to ensure safe operation under over-load conditions, each LDO features current-limit circuitry with current fold-back. The current-limit circuitry limits the current that can be drawn from the output, providing protection in over-load conditions. For additional protection under extreme over current conditions, current-fold-back protection reduces the current-limit by approximately 30% under extreme overload conditions. Enabling and Disabling the LDOs REG4 is enabled whenever either of the following conditions are met: 1) nMSTR is driven low, or The ACT8798 contains a reference bypass pin which filters noise from the reference, providing a low noise voltage reference to the LDOs. Bypass REF to G with a 0.01µF ceramic capacitor. Each of the ACT8798’s LDOs features an optional, independent output voltage discharge feature. When this feature is enabled, the LDO output is discharged to ground through a 650Ω resistance when the LDO is shutdown. This feature may be enabled or disabled via the I2C interface by writing to the REG456CFG/DISx[ ] bits. Output Capacitor Selection REG4, REG5, and REG6 each require only a small ceramic capacitor for stability. For best performance, each output capacitor should be connected directly between the OUTx and G pins as possible, with a short and direct connection. To ensure best performance for the device, the output capacitor should have a minimum capacitance of 1µF, and ESR value between 10mΩ and 200mΩ. High quality ceramic capacitors such as X7R and X5R dielectric types are strongly recommended. 2) PWRHLD is asserted high. Furthermore, once these conditions are met REG5 and REG6 maybe independently enabled or disabled via the I2C serial interface by writing the appropriate REG56/ONx[_] bit. Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 32 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 LOW-DROPOUT LINEAR REGULATORS FUNCTIONAL DESCRIPTION (CONT’D) PCB Layout Considerations PCB Layout Considerations The ACT8798’s LDOs provide good DC, AC, and noise performance over a wide range of operating conditions, and are relatively insensitive to layout considerations. When designing a PCB, however, careful layout is necessary to prevent other circuitry from degrading LDO performance. A good design places input and output capacitors as close to the LDO inputs and output as possible, and utilizes a star-ground configuration for all regulators to prevent noise-coupling through ground. Output traces should be routed to avoid close proximity to noisy nodes, particularly the SW nodes of the DC/DCs. REFBP is a filtered reference noise, and internally has a direct connection to the linear regulator controller. Any noise injected onto REFBP will directly affect the outputs of the linear regulators, and therefore special care should be taken to ensure that no noise is injected to the outputs via REFBP. As with the LDO output capacitors, the REFBP bypass capacitor should be placed as close to the IC as possible, with short, direct connections to the starground. Avoid the use of via whenever possible. Noisy nodes, such as from the DC/DCs, should be routed as far away from REFBP as possible. Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 33 - www.active-semi.com Copyright © 2008 Active-Semi, Inc. ACT8798 Rev0, 10-Oct-08 PACKAGE OUTLINE AND DIMENSIONS PACKAGE OUTLINE TQFN44-24 PACKAGE OUTLINE AND DIMENSIONS D D/2 SYMBOL E/2 E PIN #1 INDEX AREA DIMENSION IN MILLIMETERS DIMENSION IN INCHES MIN MAX MIN MAX A 0.700 0.800 0.028 0.031 A1 0.000 0.050 0.000 0.002 A3 0.200 REF 0.008 REF D/2 x E/2 A A3 A1 0.180 0.300 0.007 0.012 D 3.850 4.150 0.152 0.163 E 3.850 4.150 0.152 0.163 D2 2.500 2.800 0.098 0.110 E2 2.500 2.800 0.098 0.110 e D2 L b b L R e K 0.500 BSC 0.350 0.450 0.200 TYP 0.200 --- 0.020 BSC 0.014 0.018 0.008 TYP 0.008 --- E2 PIN #1 INDEX AREA D/2 x E/2 K R Active-Semi, Inc. reserves the right to modify the circuitry or specifications without notice. Users should evaluate each product to make sure that it is suitable for their applications. Active-Semi products are not intended or authorized for use as critical components in lifesupport devices or systems. Active-Semi, Inc. does not assume any liability arising out of the use of any product or circuit described in this datasheet, nor does it convey any patent license. Active-Semi and its logo are trademarks of Active-Semi, Inc. For more information on this and other products, contact [email protected] or visit http://www.active-semi.com. For other inquiries, please send to: 1270 Oakmead Parkway, Suite 310, Sunnyvale, California 94085-4044, USA Innovative PowerTM ActivePMUTM is a trademark of Active-Semi. I2CTM is a trademark of Philips Electronics. - 34 - www.active-semi.com Copyright © 2008 Active-Semi, Inc.