19-3349; Rev 2; 4/05 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs Applications PDAs Organizers Cellular and Cordless Phones MP3 Players Handheld Devices Features ♦ Minimum External Components ♦ Efficient Step-Down DC-DC Powers CPU Core ♦ 1V/1.3V Selectable Core Voltage, 400mA (MAX8594) ♦ 1.3V/1.8V Selectable Core Voltage, 400mA (MAX8594A) ♦ Main LDO 3.3V, 500mA ♦ SD Card Output 3.3V, 500mA ♦ Second Core LDO 1.8V, 50mA ♦ High-Efficiency LCD Boost ♦ LCD 0V True Shutdown when Off ♦ 46µA Quiescent Current Typical Operating Circuit MAX8594 MAX8594A VIN MAIN 3.3V, 500mA MAIN SDIG 3.3V, 500mA SD CARD SLOT COR2 1.8V, 50mA COR2 IN LBI DBI MAIN ON OFF ENM SDIG ON OFF ENSD COR2 ON OFF ENC2 COR1 ON OFF ENC1 1.8V/1.3V 1.3V/1V CV LCD ON OFF PV LXC PGND TO IN 1.3V OR 1.8V (MAX8594A) 1V OR 1.3V (MAX8594) 400mA COR1 COR1 SW ENL TO MAIN LXL RS LCD 15V LFB TO MAIN GND Ordering Information LBO PART TEMP RANGE PIN-PACKAGE -40°C to +85°C 24 Thin QFN-EP* 4mm x 4mm (T2444-4) MAX8594AETG -40°C to +85°C 24 Thin QFN-EP* 4mm x 4mm (T2444-4) MAX8594ETG *EP = Exposed pad. TO MAIN REF DBO Pin Configuration appears at end of the data sheet. True Shutdown is a trademark of Maxim Integrated Products, Inc. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX8594/MAX8594A General Description The MAX8594/MAX8594A complete power-management chips for low-cost personal digital assistants (PDAs) operates from a 1-cell lithium-ion (Li+) or 3-cell NiMH battery. They include all regulators, outputs, and voltage monitors necessary for small portable devices while requiring a bare minimum of external components. Featured are three linear regulators, a boost DCDC converter for LCD bias, an efficient 4MHz buck DC-DC converter for core power, a microprocessor (µP) reset output, and low-battery shutdown in a 0.8mm high thin QFN package. The COR1 buck DC-DC converter supplies a pin-selectable output at 400mA. All linear regulators feature PMOS pass elements for efficient low-dropout operation. A MAIN LDO supplies 3.3V at 500mA. A securedigital (SD) card slot output supplies 3.3V at 500mA, and a COR2 LDO supplies 1.8V at 50mA. Each output has its own logic-controlled enable. For other output voltage combinations, contact Maxim. An LCD bias boost DC-DC converter features an onboard MOSFET and True Shutdown™ when off. This means that during shutdown, input power is disconnected from the inductor so the boost output falls to 0V rather than remaining one diode drop below the input voltage. A µP reset output clears 20ms (typ) after the COR1 output achieves regulation to ensure an orderly start. In addition, the COR1 regulator is not started until the 3.3V main output is in regulation. Also included are a 1% accurate reference and low-battery monitor. Thermal shutdown protects the die from overheating. The MAX8594/MAX8594A operate from a 3.1V to a 5.5V supply voltage and consume 46µA no-load supply current. They are packaged in a tiny, 4mm x 4mm, 24-pin thin QFN capable of dissipating 1.67W. The devices are specified for operation from -40°C to +85°C. MAX8594/MAX8594A 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs ABSOLUTE MAXIMUM RATINGS IN, PV, ENSD, ENC1, ENC2, ENL, RS, SDIG, LBI, DBI to GND ...................................................-0.3V to +6V LXL to GND ............................................................-0.3V to +30V MAIN, COR1, COR2, REF, LFB, CV, ENM, LBO, DBO, LXC, SW to GND......................................-0.3V to (VIN + 0.3V) PV to IN..................................................................-0.3V to +0.3V PGND to GND .......................................................-0.3V to +0.3V Current into LXL..........................................................300mARMS Current out of SW .......................................................300mARMS Current into LXC .........................................................400mARMS Output Short-Circuit Duration.....................................Continuous Continuous Power Dissipation (TA = +70°C) 24-Pin Thin QFN Package (derate 20.8mW/°C above +70°C) .................................1.67W Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VIN = VPV = VENSD = VENC2 = VENL = VENM = VENC1 = VDBI = VLBI = VCV = 4.0V, TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER CONDITIONS MIN TYP MAX UNITS 5.5 V GENERAL IN, PV Voltage Range 3.1 VIN Complete Shutdown Threshold VDBI = VIN, VIN falling 2.950 3.0 3.050 VDBI = VIN, VIN rising 3.135 3.3 3.525 VDBI Complete Shutdown Threshold VDBI falling 1.234 1.25 1.263 VDBI rising 1.306 1.375 1.478 VLBI rising 1.234 1.25 1.263 VLBI falling 1.103 1.125 1.140 VLBI = VIN, VIN falling 3.262 3.33 3.366 VLBI = VIN, VIN rising 3.625 3.7 3.744 Preset mode, VIN = 2.9V VIN 0.3 VLBI LBO Threshold VIN LBO Threshold DBI Input Dual Mode Threshold V V V V VIN 1.2 ADJ mode, VIN = 2.9V LBI Input Dual-Mode Threshold with Respect to IN V Preset mode, VIN = 3.2V VIN 0.3 V VIN 1.2 ADJ mode, VIN = 3.2V DBI Complete Shutdown Input Program Range VIN falling 3.0 5.5 V DBI Input Bias Current VDBI = 1.25V -50 +50 nA LBI Input Bias Current VLBI = 1.25V -50 +50 nA IN, PV Operating Current IN Operating Current Shutdown (DBI remains on, REF off), VIN = VPV = VDBI = VLBI = 2.7V 2 10 All off (REF on) 30 55 All on; LXL, LXC not switching 130 180 Main on, no load 46 75 Main on, no load, COR1 on, LXC not switching 80 110 All on except LCD, VENL = 0V, LXL and LXC not switching 115 160 Dual Mode is a trademark of Maxim Integrated Products, Inc. 2 _______________________________________________________________________________________ µA µA 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs (VIN = VPV = VENSD = VENC2 = VENL = VENM = VENC1 = VDBI = VLBI = VCV = 4.0V, TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER CONDITIONS MIN TYP MAX UNITS 300 600 1200 µs 3.218 3.3 3.383 V 550 800 1200 mA mV LDOs MAIN, SDIG Soft-Start Time MAIN Output Voltage ILOAD = 100µA to 300mA, VIN = 3.6V to 5.5V MAIN Current Limit ILOAD = 1mA MAIN Dropout Voltage SDIG Output Voltage ILOAD = 300mA 210 330 ILOAD = 500mA 350 595 3.218 3.3 3.383 V 525 718 900 mA mV ILOAD = 100µA to 200mA, VIN = 3.6V to 5.5V SDIG Current Limit SDIG Dropout Voltage 1 ILOAD = 1mA 0.75 ILOAD = 200mA 170 300 ILOAD = 500mA 525 1010 7 15 1.755 1.8 1.845 V 65 98 150 mA CV = high (MAX8594A) 1.743 1.8 1.855 CV = high (MAX8594) or CV = low (MAX8594A) 1.259 1.3 1.340 CV = low (MAX8594) 0.972 1 1.023 SDIG Reverse Leakage Current VSDIG = 5.5V, VENSD = VIN = 0V COR2 Output Voltage ILOAD = 100µA to 50mA, VIN = 3.6V to 5.5V COR2 Current Limit µA COR1 PWM BUCK COR1 Output Voltage Accuracy p-Channel On-Resistance n-Channel On-Resistance ILXC = -180mA 0.70 1.34 ILXC = -180mA, VPV = 3.1V 0.8 1.58 ILXC = 180mA 0.25 0.46 ILXC = 180mA, VPV = 3.1V 0.30 0.53 V Ω Ω p-Channel Current-Limit Threshold -0.500 -0.75 -0.925 A n-Channel Current-Limit Threshold -0.50 -0.72 -0.92 A Minimum On- and Off-Times LXC Leakage Current tON(MIN) 0.1 tOFF(MIN) 0.1 VLXC = 0V, VENC1 = 0V µs -10 +0.1 +10 µA 1.236 1.25 1.264 V 0.1 3 mV 1 3 mV REF AND RESET OUTPUT REF Voltage Accuracy IREF = 0.1µA REF Line Regulation 3.1V < VIN < 5.5V, IREF = 0.1µA REF Load Regulation 0.1µA < IREF < 10µA RS Deassert Threshold for COR1 Rising (Note 1) CV = low (MAX8594A), CV = low or CV = high (MAX8594) 88.00 90 93.25 CV = high (MAX8594A) 67.0 69 72.7 % _______________________________________________________________________________________ 3 MAX8594/MAX8594A ELECTRICAL CHARACTERISTICS (continued) MAX8594/MAX8594A 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs ELECTRICAL CHARACTERISTICS (continued) (VIN = VPV = VENSD = VENC2 = VENL = VENM = VENC1 = VDBI = VLBI = VCV = 4.0V, TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER RS Assert Threshold CONDITIONS RS Deassert Delay RS Assert Delay MIN CV = low or CV = high (MAX8594), CV = low (MAX8594A) CV = high (MAX8594A) TYP MAX 80 UNITS % 62.5 10 50mV overdrive 20 30 5 ms µs LCD LXL Voltage Range LXL Current Limit L1 = 10µH 195 LXL On-Resistance LXL Leakage Current V 275 mA 2 µA µs Ω 1.7 VLXL = 28V Maximum LXL On-Time Minimum LXL Off-Time 235 28 0.2 2 3 4 VLFB > 1.1V 0.8 1 1.2 VLFB < 0.8V (soft-start) 3.9 5 6.0 1.229 1.25 1.270 V 5 50 nA 0.01 1 µA 1 1.5 LFB Feedback Threshold LFB Input Bias Current VLFB = 1.3V SW Off-Leakage Current VSW = 0V, VPV = 5.5V, VENL = 0V SW PMOS On-Resistance µs Ω SW PMOS Peak Current Limit 700 mA SW PMOS Average Current Limit 300 mA 0.13 ms Soft-Start Time CSW = 1µF LOGIC EN_, CV Input Low Level VIN = 3.1V to 5.5V EN_, CV Input High Level VIN = 3.1V to 5.5V EN_, CV Input Leakage Current 0.35 V 0.01 1 µA 1.4 V RS, LBO, DBO Output Low Level Sinking 1mA, VIN = 2.5V 0.02 0.1 V DBO Output Low Level Sinking 100µA, VIN = 1.0V 0.02 0.1 V RS, LBO, DBO Output High Leakage VOUT = 5.5V, VIN = 5.5V 1 µA THERMAL PROTECTION Thermal-Shutdown Temperature Thermal-Shutdown Hysteresis 4 Rising temperature +160 °C 15 °C _______________________________________________________________________________________ 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs (VIN = VPV = VENSD = VENC2 = VENL = VENM = VENC1 = VDBI = VLBI = 4.0V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2) PARAMETER CONDITIONS MIN TYP MAX UNITS 5.5 V GENERAL IN, PV Voltage Range 3.1 VIN Complete Shutdown Threshold VDBI = VIN, VIN falling 2.93 3.06 VDBI = VIN, VIN rising 3.135 3.525 VDBI Complete Shutdown Threshold VDBI falling 1.228 1.264 VDBI rising 1.306 1.478 VLBI rising 1.228 1.264 VLBI falling 1.103 1.140 VLBI = VIN, VIN falling 3.248 3.366 VLBI = VIN, VIN rising 3.609 3.744 Preset mode, VIN = 2.9V VIN 0.3 VLBI LBO Threshold VIN LBO Threshold DBI Input Dual-Mode Threshold V V V V VIN 1.25 ADJ mode, VIN = 2.9V LBI Input Dual-Mode Threshold with Respect to IN V Preset mode, VIN = 3.2V VIN 0.3 V VIN 1.25 ADJ mode, VIN = 3.2V DBI Complete Shutdown Input Program Range VIN falling 3.0 5.5 V DBI Input Bias Current VDBI = 1.25V -50 +50 nA LBI Input Bias Current VLBI = 1.25V -50 +50 nA IN, PV Operating Current IN Operating Current Shutdown (DBI remains on, REF off), VIN = VPV = VDBI = VLBI = 2.7V 10 All off (REF on) 55 All on, LXL, LXC not switching 180 Main on, no load 75 Main on, no load, COR1 on, LXC not switching 110 All on except LCD, VENL = 0V, LXL and LXC not switching 160 µA µA LDOs MAIN, SDIG Soft-Start Time Ramp ILIM from 0% to 100% MAIN Output Voltage ILOAD = 100µA to 300mA, VIN = 3.6V to 5.5V MAIN Current Limit MAIN Dropout Voltage 300 1200 µs 3.209 3.383 V 550 1230 mA ILOAD = 300mA 330 ILOAD = 500mA 595 mV _______________________________________________________________________________________ 5 MAX8594/MAX8594A ELECTRICAL CHARACTERISTICS MAX8594/MAX8594A 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs ELECTRICAL CHARACTERISTICS (continued) (VIN = VPV = VENSD = VENC2 = VENL = VENM = VENC1 = VDBI = VLBI = 4.0V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2) PARAMETER SDIG Output Voltage CONDITIONS ILOAD = 100µA to 200mA, VIN = 3.6V to 5.5V SDIG Current Limit SDIG Dropout Voltage MIN TYP MAX 3.218 3.383 V 485 900 mA ILOAD = 200mA 300 ILOAD = 500mA 1250 SDIG Reverse Leakage Current VSDIG = 5.5V, VENSD = VIN = 0V COR2 Output Voltage ILOAD = 100µA to 50mA, VIN = 3.6V to 5.5V UNITS mV 15 µA 1.750 1.845 V 60 150 mA CV = high (MAX8594A) 1.743 1.855 CV = high (MAX8594) or CV = low (MAX8594A) 1.255 1.340 CV = low (MAX8594) 0.969 1.023 COR2 Current Limit COR1 PWM BUCK COR1 Output Voltage Accuracy p-Channel On-Resistance n-Channel On-Resistance ILXC = -180mA 1.34 ILXC = -180mA, VPV = 3.1V 1.58 ILXC = 180mA 0.46 ILXC = 180mA, VPV = 3.1V 0.53 V Ω Ω p-Channel Current-Limit Threshold -0.460 -0.925 A n-Channel Current-Limit Threshold -0.46 -0.92 A -10 +10 µA 1.229 LXC Leakage Current VPV = 5.5V, VLXC = 0V or VPV, VENC1 = 0V REF AND RESET OUTPUT REF Voltage Accuracy IREF = 0.1µA 1.264 V REF Line Regulation 3.1V < V < 5.5V, IREF = 0.1µA 3 mV REF Load Regulation 0.1µA < IREF < 10µA 3 mV RS Deassert Threshold for COR1 Rising (Note 1) CV = low or CV = high (MAX8594), CV = low (MAX8594A) CV = high (MAX8594A) RS Deassert Delay 88.00 93.25 67.0 72.7 10 30 28 V 180 mA µA µs % ms LCD LXL Voltage Range LXL Current Limit LXL Leakage Current Maximum LXL On-Time Minimum LXL Off-Time L1 = 10µH VLXL = 28V VLFB > 1.1V 2 0.8 280 2 4 1.2 VLFB < 0.8V (soft-start) 3.9 6.0 1.223 LFB Feedback Threshold µs 1.270 V LFB Input Bias Current VLFB = 1.3V 50 nA SW Off-Leakage Current VSW = 0V, VPV = 5.5V, VENL = 0V 1 µA 1.5 Ω SW PMOS On-Resistance 6 _______________________________________________________________________________________ 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs (VIN = VPV = VENSD = VENC2 = VENL = VENM = VENC1 = VDBI = VLBI = 4.0V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2) PARAMETER CONDITIONS MIN TYP MAX UNITS 0.35 V 1 µA LOGIC EN_, CV Input Low Level VIN = 3.1V to 5.5V EN_, CV Input High Level VIN = 3.1V to 5.5V 1.4 EN_, CV Input Leakage Current V RS, LBO, DBO Output Low Level Sinking 1mA, VIN = 2.5V 0.1 V DBO Output Low Level Sinking 100µA, VIN = 1.0V 0.1 V RS, LBO, DBO Output High Leakage VOUT = 5.5V, VIN = 5.5V 1 µA Note 1: The reset trip point tracks the COR1 voltage. For example, a minimum reset spec does not occur with a maximum COR1 spec, and a minimum COR1 spec does not occur with a maximum reset spec. Note 2: Specifications to -40°C are guaranteed by design, not production tested. Typical Operating Characteristics (Circuit of Figure 2, VIN = 4V, TA = +25°C, unless otherwise noted.) 350 300 250 200 150 100 50 0 700 600 500 400 300 100 200 300 400 LOAD CURRENT (mA) 500 600 3.25 3.00 2.75 2.50 2.25 200 2.00 100 1.75 0 0 3.50 MAX8594/MAX8594A toc03 400 800 MAIN OUTPUT VOLTAGE vs. LOAD CURRENT MAX8594/MAX8594A toc02 DROPOUT VOLTAGE (mV) 450 DROPOUT VOLTAGE (mV) MAX8594/MAX8594A toc01 500 SDIG DROPOUT VOLTAGE vs. LOAD CURRENT OUTPUT VOLTAGE (V) MAIN DROPOUT VOLTAGE vs. LOAD CURRENT 1.50 0 100 200 300 400 LOAD CURRENT (mA) 500 600 0 100 200 300 400 500 600 700 800 900 LOAD CURRENT (mA) _______________________________________________________________________________________ 7 MAX8594/MAX8594A ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (continued) (Circuit of Figure 2, VIN = 4V, TA = +25°C, unless otherwise noted.) SDIG OUTPUT VOLTAGE vs. LOAD CURRENT COR1 OUTPUT VOLTAGE vs. LOAD CURRENT 3.00 2.75 2.50 2.25 MAX8594/MAX8594A toc05 OUTPUT VOTLAGE (V) 3.25 1.9 1.8 1.7 OUTPUT VOLTAGE (V) MAX8594/MAX8594A toc04 3.50 2.00 1.6 1.5 1.4 1.3 1.2 1.1 1.75 1.0 1.50 0.9 0 100 200 300 400 500 600 700 0 100 200 300 LOAD CURRENT (mA) LOAD CURRENT (mA) COR2 OUTPUT VOLTAGE vs. LOAD CURRENT LOAD-TRANSIENT MAIN 1.80 1.78 1.76 1.74 400 MAX8594/MAX8594A toc07 MAX8594/MAX8594A toc06 1.82 OUTPUT VOLTAGE (V) 50mV/div AC-COUPLED VMAIN 1.72 1.70 1.68 IOUT 1.66 100mA/div 1.64 0 1.62 1.60 0 20 40 60 80 100 100µs/div LOAD CURRENT (mA) INPUT CURRENT vs. INPUT VOLTAGE LOAD-TRANSIENT COR1 MAX8594/MAX8594A toc08 MAX8594/MAX8594A toc09 60 50 20mV/div AC-COUPLED VCOR1 IOUT 100mA/div 0 INPUT CURRENT (µA) MAX8594/MAX8594A 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs VIN FALLING 40 30 VIN RISING 20 10 0 40µs/div 0 1 2 3 4 5 INPUT VOLTAGE (V) 8 _______________________________________________________________________________________ 6 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs LCD EFFICIENCY vs. LOAD CURRENT RS AND OUTPUT TIMING MAX8594/MAX8594A toc10 MAX8594/MAX8594A toc11 90 85 5V/div 0 VMAIN 2V/div VRS 0 5V/div 0 VCOR1 1V/div 80 EFFICIENCY (%) VIN 75 VLCD = 15V VLCD = 18V 70 65 60 55 50 0 45 40 0 20ms/div 1 2 3 4 5 LOAD CURRENT (mA) LCD OUTPUT VOLTAGE vs. INPUT VOLTAGE LCD OUTPUT VOLTAGE vs. LOAD CURRENT 17.8 17.6 17.4 17.2 MAX8594/MAX8594A toc13 OUTPUT VOLTAGE (V) 18.0 18.04 18.03 OUTPUT VOLTAGE (V) MAX8594/MAX8594A toc12 18.2 18.02 18.01 18.00 17.99 17.98 17.0 17.97 17.96 16.8 0 2 4 6 8 10 3.5 12 4.0 4.5 5.0 LOAD CURRENT (mA) INPUT VOLTAGE (V) LCD SWITCHING WAVEFORMS SDIG RESPONSE TO ENSD MAX8594/MAX8594A toc14 VIN MAX8594/MAX8594A toc15 20mV/div AC-COUPLED 50mV/div AC-COUPLED VLCD 5.5 2V/div VENSD 20V/div VLX 1V/div ILX 200mA/div VSDIG ILOAD = 100mA 4µs/div 200µs/div _______________________________________________________________________________________ 9 MAX8594/MAX8594A Typical Operating Characteristics (continued) (Circuit of Figure 2, VIN = 4V, TA = +25°C, unless otherwise noted.) Typical Operating Characteristics (continued) (Circuit of Figure 2, VIN = 4V, TA = +25°C, unless otherwise noted.) LCD RESPONSE TO ENL MAIN RESPONSE TO ENM MAX8594/MAX8594A toc16 MAX8594/MAX8594A toc17 2V/div VENL 2V/div VENM LCD BOOST SOFT-START SW TURN-ON 5V/div VLCD 1V/div VMAIN ILOAD = 100mA 400µs/div 200µs/div RS AND COR1 RESPONSE TO ENC1 COR1 RESPONSE TO ENC1 MAX8594/MAX8594A toc19 MAX8594/MAX8594A toc18 RLOAD = 10Ω RLOAD = 10Ω VENC1 2V/div VENC1 2V/div VCOR1 1V/div VRS 5V/div ILXC 200mA/div 500mV/div VCOR1 0 200mA/div ILXC 10ms/div 40µs/div FOR RS RESPONSE, SEE RS AND COR1 RESPONSE TO ENC1 MAX8594/MAX8594A toc20 90 85 2V/div VENC2 80 VIN = 5V 75 MAX8594/MAX8594A toc21 COR1 EFFICIENCY vs. LOAD CURRENT WITH 1V OUTPUT COR2 RESPONSE TO ENC2 EFFICIENCY (%) MAX8594/MAX8594A 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs VIN = 4V 70 65 VIN = 3.6V 60 55 1V/div VCOR2 50 45 MAX8594 40 200µs/div 0.1 1 10 100 LOAD CURRENT (mA) 10 ______________________________________________________________________________________ 1000 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs COR1 EFFICIENCY vs. LOAD CURRENT WITH 1.3V OUTPUT VIN = 4V 70 90 VIN = 3.6V 65 60 85 60 45 55 40 50 1000 100 VIN = 3.6V 70 50 10 VIN = 4V 75 65 1 VIN = 5V 80 55 0.1 MAX8594/MAX8594A toc22a EFFICIENCY (%) VIN = 5V 75 95 EFFICIENCY (%) 85 80 100 MAX8594/MAX8594A toc22 90 COR1 EFFICIENCY vs. LOAD CURRENT WITH 1.8V OUTPUT 0.1 1 10 100 LOAD CURRENT (mA) LOAD CURRENT (mA) LIGHT-LOAD SWITCHING COR1 HEAVY-LOAD SWITCHING COR1 1000 MAX8594/MAX8594A toc23 MAX8594/MAX8594A toc24 ILOAD = 20mA ILOAD = 200mA 5V/div 0 VLXC 50mV/div AC-COUPLED VCOR1 5V/div 0 VLXC 50mV/div AC-COUPLED VCOR1 200mA/div ILXC ILXC 200mA/div 200ns/div 1µs/div COR1 RESPONSE TO CV MAX8594/MAX8594A toc25 1.3V/1.8V 1V/1.3V VCOR1 500mV/div 0 VCV 2V/div 40µs/div ______________________________________________________________________________________ 11 MAX8594/MAX8594A Typical Operating Characteristics (continued) (Circuit of Figure 2, VIN = 4V, TA = +25°C, unless otherwise noted.) 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs MAX8594/MAX8594A Pin Description PIN 12 NAME FUNCTION 1 SDIG 3.3V, 500mA LDO Output for Secure-Digital Card Slot. SDIG has reverse current protection so SDIG can be biased when no power is present at IN. SDIG output turns off when VIN is below the DBI threshold, ENSD goes low, or MAIN is out of regulation. When SDIG turns off, the output is discharged at a rate depending on the load and the internal feedback resistors (typically 1.3MΩ). 2 IN Input Voltage to the MAX8594/MAX8594A. Bypass IN to GND with a 1µF ceramic capacitor. 3 RS Reset Output. RS is an active-low, open-drain output that goes high impedance 20ms (typ) after COR1 is in regulation. COR1 does not turn on until MAIN is in regulation. If MAIN falls out of regulation, COR1 turns off and RS goes low. If MAIN is still in regulation, then RS goes low when VIN is below the DBI threshold. RS goes low when ENC1 is low. 4 LBO Low-Battery Detector Open-Drain Output. LBO is an active-low, open-drain output that goes high impedance when VIN is greater than both the DBI and LBI thresholds. LBO goes low when VIN falls below the LBI threshold. 5 DBO Dead-Battery Detector Open-Drain Output. When VIN is below the DBI threshold, both DBO and LBO go low, all outputs shut down, and the MAX8594/MAX8594A enter the lowest possible quiescentcurrent state. Once this occurs, MAIN does not turn back on until both VIN exceeds the DBI threshold and ENM = high. DBO is an active-low, open-drain output that goes high impedance when VIN exceeds the DBI threshold. 6 DBI Dead-Battery Detector. DBI remains active at all times. If DBI = IN, the DBI threshold is 3.0V when IN is falling and 3.3V when rising. The DBI threshold can also be adjusted to other values by connecting DBI to a resistor voltage-divider. Also see the DBO description. 7 LBI Low-Battery Detector. If LBI = IN, the LBI threshold is 3.33V when IN is falling and 3.7V when rising. The LBI threshold can also be adjusted to other values by connecting LBI to a resistor voltagedivider. Also see the LBO description. 8 CV Selects 1V or 1.3V COR1 Output Voltage for MAX8594, and 1.3V or 1.8V COR1 for MAX8594A. Drive CV high or connect to IN for a 1.3V COR1 output (1.8V COR1 for MAX8594A). Drive CV low or connect to GND for a 1V COR1 output (1.3V COR1 for MAX8594A). 9 ENM Enable Input for MAIN. No other outputs turn on until MAIN is in regulation. If MAIN is pulled out of regulation, all other outputs turn off and RS goes low. MAIN cannot be activated when VIN is below the DBI threshold. 10 GND Ground 11 REF 1.25V 1% Reference. Bypass REF with a 0.1µF capacitor to GND. REF is enabled when VIN is greater than the DBI threshold. REF is off when VIN is below the DBI threshold. 12 LFB LCD Feedback Input. Connect LFB to a resistor-divider network between the LCD output and GND. The feedback threshold is 1.25V. LCD turns off when VIN is below the DBI threshold, when ENL goes low, or when MAIN is out of regulation. When off, the LCD output is discharged at a rate depending on the load and the external feedback resistors (typically 2.4MΩ). 13 ENL Enable Input for LCD (Boost Regulator). Drive ENL high to activate the LCD boost. Drive ENL low to shut down the LCD output. The LCD converter cannot be activated when VIN is below the DBI threshold or before MAIN is in regulation. 14 LXL LCD Boost Switch. Connect LXL to a boost inductor and Schottky diode. See Figure 1. ______________________________________________________________________________________ 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs PIN NAME FUNCTION 15 SW LCD True-Shutdown Switch Output. SW is the power source for the LCD boost inductor. SW turns on when ENL is high. For best efficiency, bypass SW with a 4.7µF capacitor to GND. SW is disconnected from PV when LCD is shut down. 16 PV Power Input for COR1 Buck Converter and LCD True-Shutdown Switch. Connect IN to PV. 17 PGND 18 LXC 19 ENC1 Enable Input for Primary Core Buck Converter (COR1). Drive ENC1 high to turn on COR1 and low to turn off. COR1 cannot be activated if VIN is below the DBI threshold or before MAIN is in regulation. 20 ENSD Enable Input for Secure Digital Card (SDIG). Drive ENSD low to turn off SDIG and high to turn on. SDIG cannot be activated when VIN is below the DBI threshold or before MAIN is in regulation. 21 COR1 Feedback Sense Input for COR1 Output. COR1 turns off when VIN is below the DBI threshold, when ENC1 goes low, or when MAIN is out of regulation. When off, the output is discharged by LXC through an internal 1MΩ (typ) resistor. 22 ENC2 Enable Input for Secondary Core LDO (COR2). Drive ENC2 high to turn on COR2 and low to turn off. COR2 cannot be activated when VIN is below the DBI threshold or before MAIN is in regulation. COR2 can be activated when VIN is greater than the DBI threshold and MAIN is in regulation. 23 COR2 1.8V, 50mA LDO Output for Secondary Core. COR2 turns off when VIN is below the DBI threshold, when ENC2 goes low, or when MAIN is out of regulation. The COR2 output is discharged at a rate depending on the load and the internal feedback resistors (typically 700kΩ). 24 MAIN 3.3V, 500mA LDO Output for Main Supply. MAIN output turns off when VIN is below the DBI threshold or when ENM goes low. When off, the output is discharged at a rate depending on the load and the internal feedback resistors (1.3MΩ typ). — EP Power Ground COR1 Switching Node. Connect LXC to the COR1 inductor. See Figure 1. Exposed Pad. Connect to ground for enhanced power dissipation. ______________________________________________________________________________________ 13 MAX8594/MAX8594A Pin Description (continued) MAX8594/MAX8594A 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs AC ADAPTER INPUT 4.15V TO 7V 1µF DC MAX8601 POWER INPUT BATT 1µF C1 1µF Li-ION BATTERY MAX8594 MAX8594A MAIN IN 3.3V, 500mA MAIN C2 4.7µF LBI SDIG USB INPUT 4.15V TO 6V 1µF DBI USB COR2 MAIN ON OFF DIE THERMAL CONTROL CHARGE CONTROL EN 500mA 100mA C3 4.7µF POK USEL LOGIC GND ISEL C4 2.2µF ENM SDIG ON OFF ENSD COR2 ON OFF ENC2 COR1 ON OFF ENC1 1.8V/1.3V 1.3V/1V LCD ON OFF C5 0µF LXC 1.3V OR 1.8V C6 (MAX8594A) 2.2µF 1V OR 1.3V (MAX8594) 400mA COR1 L2 2.2µH PGND COR1 CV SW L1 10µH MURATA LQH32C ENL TO MAIN R8 1MΩ 1.8V, 50mA COR2 TO IN PV FLT CHG 3.3V, 500mA SD CARD SLOT LXL C9 47pF R1 2.2MΩ RS LFB TO MAIN R7 1MΩ GND R2 200kΩ LBO REF TO MAIN C10 0.1µF R6 1MΩ DBO Figure 1. Typical Application Circuit with Charger 14 C7 4.7µF ______________________________________________________________________________________ LCD C8 15V 1µF 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs POWER INPUT IN ENM SDIG C3 4.7µF LDO CONTROL ON OFF ENSD ON OFF ENC2 ON OFF ENC1 3.3V, 500mA MAIN C2 4.7µF LDO CONTROL C1 1µF ON OFF MAIN COR2 1.8V/1.3V 1.3V/1V C4 2.2µF LDO CONTROL CV PV 3.3V, 500mA SD CARD SLOT 1.8V, 50mA COR2 TO IN C5 0µF PWM BUCK MAX8594/MAX8594A MAX8594 MAX8594A C6 2.2µF LXC 1.3V OR 1.8V (MAX8594A) 1V OR 1.3V (MAX8594) 400mA COR1 L2 2.2µH PGND COR1 FB TO PV SW MAINOK LCD ON OFF LCD OFF SWITCH L1 10µH MURATA LQH32C ENL C7 4.7µF LXL TO MAIN R8 1MΩ LFB RS 20ms AFTER COR1 OK TO MAIN C9 47pF R1 2.2MΩ LCD BOOST LCD C8 15V 1µF R2 200kΩ GND R7 1MΩ LBO REF REF IN C10 0.1µF TO MAIN R6 1MΩ DBO LBI DBI TO IN TO IN Figure 2. Block Diagram ______________________________________________________________________________________ 15 MAX8594/MAX8594A 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs Detailed Description COR1 Step-Down DC-DC Converter The COR1 regulator is a proprietary hysteretic PWM control step-down converter that supplies up to 400mA. The output voltage is set to either 1V or 1.3V by CV for the MAX8594 and 1.3V or 1.8V for the MAX8594A. Under moderate to heavy loading, COR1 operates in a low-noise PWM mode with constant frequency and modulated pulse width. Switching harmonics generated by fixed-frequency operation are consistent and easily filtered. With light loads (<30mA), COR1 operates in an efficiency-enhanced Idle Mode™ during which the converter switches only as needed to service the load. Linear Regulators Power for main logic, a SD card slot, and CODEC are provided by three LDOs: • MAIN—Provides 3.3V at a guaranteed 500mA with a typical current limit of 800mA. • SDIG—Provides 3.3V at a guaranteed 500mA for SD cards with a typical current limit of 718mA. • COR2—Provides 1.8V at a guaranteed 50mA for a CODEC core with a typical current limit of 98mA. Note that it may not be possible to draw the full rated current of MAIN and SDIG at all operating input voltages due to the dropout limitations of those regulators. The typical dropout resistance of the MAIN regulator is 0.7Ω (350mV drop at 500mA), and the typical dropout resistance of the SDIG regulator is 0.85Ω (525mV drop at 500mA). All voltage outputs have separate enable inputs (ENM, ENL, ENSD, ENC1, and ENC2); however, no other output turns on until MAIN is in regulation. MAIN cannot be activated until VIN exceeds the DBI threshold. When SDIG is turned off, reverse current is blocked so the SDIG output can be biased with an external source when no power is present at IN. Leakage current is typically 3µA with 3.3V at SDIG. function is ideal for applications that require the output voltage to fall to 0V in shutdown (True Shutdown). If True Shutdown is not required, the SW switch can be bypassed by connecting the boost inductor directly to PV and removing the bypass cap on SW (C7 in Figure 1). System Sleep All regulated outputs turn off when VDBI < 1.25V (or VIN = 3.0V if DBI = IN, Figure 1). The MAX8594/MAX8594A resume normal operation when VDBI >1.375V (or VIN = 3.3V if DBI = IN, Figure 1). Reset Output (RS) Reset RS asserts when COR1 falls 20% below its set level (38% for 1.8V setting in the MAX8594A). RS is an open-drain, active-low output. Connect a pullup resistor from RS to the logic supply of the gate receiving the reset signal. RS deasserts a minimum of 10ms after the COR1 output is in regulation. Upon application of valid input power, the MAIN output activates first (if ENM = high) followed by other outputs (if EN_ = high). Power and output sequencing are shown in Figure 3. VIN VIN = 3.7V VIN = 3.3V VIN = 3.33V VIN = 3.0V MAIN AT 90% MAIN AT 86% 3.3V MAIN COR1 COR1 AT 90% RS 20ms RS DEASSERT DELAY LBO DBO LCD DC-DC Boost The MAX8594/MAX8594A include a low-current, highvoltage boost DC-DC converter for LCD bias. This circuit can output up to 28V and is adjustable with either an analog or PWM control signal using external components. Figure 3. Power Sequence for Rising and Falling Input Voltage. Note that VIN thresholds are for LBI and DBI connected to VIN. Other thresholds can be set with resistors. SW provides an input-power disconnect for the LCD when ENL is low (off). The input-power disconnect Idle Mode is a trademark of Maxim Integrated Products, Inc. 16 ______________________________________________________________________________________ 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs 2) 3) 4) When VIN rises above the DBI threshold (3.3V if DBI = IN), DBO goes high impedance immediately and the part turns on. The MAIN LDO turns on if ENM = HIGH. When the MAIN output reaches 90% of its nominal voltage, or 2.97V, all other regulators turn on if they are enabled. RS goes high impedance 20ms after COR1 reaches 90% of its nominal voltage (69% when 1.8V setting in the MAX8594A is used). 5) When VIN rises above the LBI threshold (3.7V if LBI = IN), LBO goes high impedance. As IN decreases, sequencing is as follows: 1) 2) 3) When VIN falls to the LBO threshold (3.33V if LBI = IN), LBO is pulled to GND. If VIN falls to the DBI threshold (3.0V if LBI = IN) before the MAIN output falls to 2.838V, DBO and RS go low, all regulators turn off, and the part is shut down. If the MAIN output falls below 86% of its nominal voltage (2.838V) before IN reaches the DBI threshold (3.0V if DBI = IN), RS is pulled to GND and all other outputs turn off, but MAIN remains on (in dropout) and DBO remains high until IN falls to the DBI threshold. Applications Information COR1 Buck Output COR1 Inductor A 2.2µH inductor with a saturation current of at least 500mA is recommended. For lower load currents, the inductor current rating may be reduced. For maximum efficiency, the inductor’s DC resistance should be as low as possible. Note that core materials differ among manufacturers and inductor types, resulting in variations in efficiency. The COR1 output capacitor C6 (Figure 1) is required to keep the output voltage ripple small; 2.2µF is recommended for most applications. Due to the pulsating nature of input current in a buck converter, a low-ESR input capacitor is required for input voltage filtering and to minimize interference with other circuits. The impedance of the input capacitor, C5 (Figure 1), should be kept very low at the switching frequency. A minimum value of 4.7µF is recommended at PV for most applications. The input capacitor can be increased to further improve input filtering. LDO Output Capacitors (MAIN, SDIG, COR2) Capacitors are required at each LDO output of the MAX8594/MAX8594A for stable operation over the full load and temperature range. See Figure 1 for recommended capacitor values for each output. To reduce noise and improve load-transient response, larger output capacitors up to 10µF can be used. Surface-mount ceramic capacitors have very low ESR and are commonly available in values up to 10µF. X7R and X5R dielectrics are recommended. Note that some ceramic dielectrics, such as Z5U and Y5V, exhibit large capacitance and ESR variation with temperature and require larger than the recommended values to maintain stability overtemperature. Setting LBI and DBI The DBI and LBI inputs monitor input voltage (usually a battery) and trigger the DBO and LBO outputs. With LBI and DBI connected to IN, the LBI and DBI thresholds are internally set. For a rising input voltage, DBO goes high when VIN exceeds 3.3V and LBO goes high when VIN exceeds 3.7V. For a falling input voltage, LBO goes low when VIN falls below 3.3V and DBO goes low when V IN falls below 3.0V (see also the Electrical Characteristics table and Figure 3). Alternatively, the LBI and DBI thresholds can be set with external resistors as shown in Figures 4 and 5. COR1 Capacitors Ceramic input and output capacitors are recommended. For best stability over a wide temperature range, use capacitors with an X5R or X7R dielectric due to their low ESR and low temperature coefficient. ______________________________________________________________________________________ 17 MAX8594/MAX8594A Power Sequencing As VIN increases from 0V, sequencing is as follows: 1) The DBI comparator is always on. DBO, LBO, and RS are pulled low at approximately VIN = 0.7V. MAIN, SDIG, COR1, COR2, and LCD are off. MAX8594/MAX8594A 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs IN IN R3 DBI (1.25V FALLING, 1.375V RISING) LBI (1.125V FALLING, 1.25V RISING) R6 R4 DBI (1.25V FALLING, 1.375V RISING) R5 LBI (1.125V FALLING, 1.25V RISING) MAX8594 MAX8594A R8 R7 R9 MAX8594 MAX8594A Figure 4. Setting the DBI and LBI Threshold with Three External Resistors Figure 5. Setting the DBI and LBI Thresholds with Four Resistors In Figure 4, one three-resistor-divider can set both DBI and LBI according to the following equations (shown for setting falling thresholds). Choose the lower resistor of the divider chain (R5 in Figure 4) to be between 100kΩ and 250kΩ. The equations for the two upper resistordividers as a function of each (falling) threshold are: Alternately, LBI and DBI can be set with separate resistor-dividers. The resistor calculation is simpler and the two settings do not interact, but one more resistor is needed and battery drain is slightly higher due to the extra resistor load. Choose the lower resistor of each divider chain (R7 and R9 in Figure 5) to be between 100kΩ and 250kΩ. The equations for upper resistordividers as a function of each (falling) threshold are: V 1.25 R 3 = R5 x LBFALL x 1 − 1.125 VDBFALL R4 = R5 x 1.25 x VLBFALL −1 1.125 x VDBFALL where VDBFALL and VLBFALL are the desired falling thresholds to trigger the DBO and LBO outputs, respectively. Once those thresholds are selected, the rising DBI and LBI thresholds are: VDBRISE = 1.375 x R 3 + R4 + R5 R4 + R5 V R6 = R7 x DBFALL − 1 1.25 V R8 = R9 x LBFALL − 1 1.125 where VDBFALL and VLBFALL are the desired falling thresholds to trigger the DBO and LBO outputs, respectively. Once those thresholds are selected, the rising DBI and LBI thresholds are: VDBRISE = 1.375 x VLBRISE = 1.25 x R 3 + R4 + R5 R5 VLBRISE = 1.25 x R6 + R7 R7 R8 + R9 R9 Note that the low-battery threshold should not be set below the dead-battery threshold because both DBO 18 ______________________________________________________________________________________ 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs SIMPLIFIED DC-DC CONVERTER I1 R1 AVDD VDOUT ERROR AMP RD DAC ID R2 I2 VREF 1.25V CONTROL VOUT MAX8594 MAX8594A Figure 6. Adjusting the Output Voltage with a DAC and LBO are automatically driven low and the part is shut down when the DBI threshold is crossed (going low). LCD Boost Output LCD Inductor The LCD boost is designed to operate with a wide range of inductor values (4.7µH to 150µH). Smaller inductance values typically offer smaller size for a given series resistance or saturation current. Smaller values cause LX to switch more frequently for a given load and can reduce efficiency at low load currents. Larger values reduce switching losses due to less frequent switching for a given load, but higher DC resistance can reduce efficiency. Note that for inductors larger than 43µH, the peak inductor current does not reach 250mA before the LXL maximum on-time (3µs) expires. This reduces output current but may be beneficial for light-load efficiency. A 10µH inductor provides a good balance and works well for most applications. The inductor’s saturation current rating should be greater than the peak switching current (250mA). LCD Diode Schottky diodes rated at 250mA or more, such as the MBR0530 or Nihon EP05Q03L, are recommended. The diode reverse-breakdown voltage rating must be greater than the LCD output voltage. LCD Capacitors For most applications, use a ceramic 1µF output capacitor. This typically provides a peak-to-peak output ripple of 30mV. In addition, bypass IN with 1µF and SW with 4.7µF ceramic capacitors. An LCD feed-forward capacitor, connected from the output to LFB, improves stability over a wide range of battery voltages. A 47pF capacitor is sufficient for most applications; however, the optimum value is affected by PC board layout. Setting LCD Voltage Adjust the output voltage by connecting a voltagedivider from the LCD output to LFB (see Figure 1). Select R2 between 10kΩ and 200kΩ. Calculate R1 with the following equation: V R1 = R2 x OUT − 1 V LFB where VLFB = 1.25V and VOUT can range from VIN to 28V. The input bias current of LFB is typically only 5nA, allowing large-value resistors to be used. For less than 1% error, the current through R2 should be greater than 100 times the feedback input bias current (ILFB). LCD Adjustment The LCD boost output can be digitally adjusted by either a DAC or PWM signal. DAC Adjustment Adding a DAC and a resistor, RD, to the divider circuit (Figure 6) provides DAC adjustment of VOUT. Ensure that VOUT(MAX) does not exceed the LCD panel rating. The output voltage (VOUT) as a function of the DAC voltage (VDOUT) is calculated using the following formula: R1 (1.25 − VDOUT ) xR1 VOUT = 1.25 x 1 + + RD R2 ______________________________________________________________________________________ 19 MAX8594/MAX8594A VIN MAX5365 MAX8594/MAX8594A 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs Using PWM Signals Many µPs have the ability to create PWM outputs. These are digital outputs, based on either 16-bit or 8-bit counters, with a programmable duty cycle. In many applications, they are suitable for adjusting the output of the MAX8594/MAX8594A as seen in Figure 7. The circuit consists of the PWM source, capacitor C11, and resistors RD and RW. To analyze the transfer function of the PWM circuit, it is easiest to first simplify it to its Thevenin equivalent. The Thevenin voltage is calculated using the following formula: VTHEV = (D x VOH ) + (1 − D) x VOL where D is the duty cycle of the PWM signal, VOH is the PWM output high level (often 3.3V), and V OL is the PWM output low level (usually 0V). For CMOS logic, this equation simplifies to: VTHEV = D x VDD where VDD is the logic-high output voltage of the PWM output. The Thevenin impedance is the sum of resistors RW and RD: RTHEV = RD + RW The output voltage (VOUT) as a function of the PWM average voltage (VTHEV) is: R1 (1.25 − VTHEV ) xR1 VOUT = 1.25 x 1 + + R THEV R2 When using the PWM adjustment method, RD isolates the capacitor from the feedback loop of the MAX8594/MAX8594A. The cutoff frequency of the lowpass filter is defined as: fC = 1 2 x π xR THEV xC11 The cutoff frequency should be at least two decades below the PWM frequency to minimize the induced AC ripple at the output. An important consideration is the turn-on transient created by the initial charge on filter capacitor C11. This capacitor forms a time constant with RTHEV, causing the output to initialize at a higher than intended voltage. This overshoot is minimized by scaling RD as high as possible compared to R1 and R2. Alternatively, the µP can briefly keep the LCD disabled until the PWM voltage has had time to stabilize. 20 SW C7 4.7µF LCD C8 15V 1µF LXL C9 47pF R1 2.2MΩ LFB R2 200kΩ CONNECTION FOR PWM-CONTROLLED LCD BIAS RD RW C11 Figure 7. PWM-Controlled LCD Bias PC Board Layout and Grounding Careful PC board layout is important for minimizing ground bounce and noise. Keep the MAX8594/ MAX8594A’s ground pin and the ground leads of the input and output capacitors less than 0.2in (5mm) apart. In addition, keep all connections to LFB, COR1, LXC, and LXL as short as possible. In particular, external feedback resistors should be as close to LFB as possible. To minimize output voltage ripple and to maximize output power and efficiency, use a ground plane and solder PGND and exposed pad directly to the ground plane. Refer to the MAX8594 evaluation kit for a layout example. Thermal Considerations In most applications, the circuit is located on a multilayer board and full use of the four or more layers is recommended. For heat dissipation, connect the exposed backside pad of the thin QFN package to a large ground plane, preferably on a surface of the board that receives good airflow. Typical applications use multiple ground planes to minimize thermal resistance. Avoid large AC currents through the ground plane. ______________________________________________________________________________________ 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs LXC PGND PV SW LXL ENL TOP VIEW 18 17 16 15 14 13 ENC1 19 12 LFB ENSD 20 11 REF COR1 21 10 GND 9 ENM MAX8594 MAX8594A CV MAIN 24 7 LBI 1 2 3 4 5 6 DBI 8 DBO 23 LBO COR2 RS 22 IN ENC2 SDIG TRANSISTOR COUNT: 3436 PROCESS: BiCMOS THIN QFN ______________________________________________________________________________________ 21 MAX8594/MAX8594A Pin Configuration Chip Information Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) 24L QFN THIN.EPS MAX8594/MAX8594A 5-Output PMICs with DC-DC Core Supply for Low-Cost PDAs PACKAGE OUTLINE, 12, 16, 20, 24, 28L THIN QFN, 4x4x0.8mm 21-0139 D 1 2 PACKAGE OUTLINE, 12, 16, 20, 24, 28L THIN QFN, 4x4x0.8mm 21-0139 D 2 2 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 22 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2005 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc.