19-1438; Rev 0; 3/99 NUAL KIT MA ATION EET H S A EVALU T WS DA O L L O F Wireless and Satellite Handset Power-Management ICs Features ♦ 90% Efficient, 500mA Step-Down Converter The MAX886/MAX888 power-management ICs are complete power systems for wireless and satellite handsets. The devices operate from 3 to 6-cell NiCd/NiMH batteries or from 1 or 2-cell Li-Ion batteries. They incorporate a high-efficiency, step-down DC-DC converter, a regulated 5V charge pump, and four linear regulators. The regulators supply power to the SIM, LCD, BB, DSP, and RF sections of a cellular telephone handset. The step-down converter and linear regulator outputs are adjustable by internal 4-bit DACs, programmable through the I2C™compatible serial interface. A pushbutton on/off scheme activates a 5µA low-power shutdown mode. The devices also feature a low-battery detector output and an internal start-up timer. ♦ Two 100mA DAC-Controlled LDOs One 200mA DAC-Controlled LDO One 20mA DAC-Controlled LDO ♦ 3 to 6-Cell NiCd or NiMH Operation 1 or 2-Cell Li-Ion Operation ♦ +2.7V to +12V Input Voltage Range ♦ 250µA Standby (PFM) Quiescent Current ♦ 5µA Shutdown Current ♦ I2C-Compatible Serial Interface ♦ Selectable 375kHz, 535kHz, 670kHz, 925kHz (or Synchronizable) Switching Frequency The MAX886/MAX888 differ in output voltage range and power-on reset voltage. The MAX886 has a higher preset voltage range and is intended for 2-cell Li-Ion or 5/6-cell NiCd/NiMH batteries. The MAX888 has a lower preset voltage range and is intended for 1-cell Li-Ion or 3/4-cell NiCd/NiMH batteries. Both devices are available in a space-saving, 32-pin TQFP package. ♦ Power-On Reset and Start-Up Timer ♦ Thermal Overload Protection ♦ Pushbutton On/Off Control ♦ Space-Saving 32-Pin TQFP Package (7mm x 7mm) Ordering Information Applications Satellite Phones Wireless Handsets PART Private Mobile Radio (PMR) GSM Cellular/PCS Telephones TEMP. RANGE PIN-PACKAGE MAX886ECJ* -40°C to +85°C 32 TQFP MAX888ECJ -40°C to +85°C 32 TQFP * Future product—contact factory for availability. Pin Configuration appears at end of data sheet. Typical Operating Circuit IN 2.7V TO 12V MAIN POWER (UP TO 500mA) LX BATT PGND LOW-BATTERY DETECT I2C-COMPATIBLE SERIAL INTERFACE ON/OFF CONTROL (OPTIONAL) LBI MAX886 MAX888 OUT0 LBO OUT1 Tx SECTION POWER (UP TO 100mA) SDA OUT2 DSP POWER (UP TO 200mA) ON RESET SCL POWER-ON RESET OFF OUT3 3V/5V SIM CARD POWER (UP TO 20mA) SYNC OUT4 LCD/VCO/TXCO POWER (UP TO 100mA) C+ OUT5 Rx SECTION POWER (UP TO 100mA) C- GND ONSTAT ON STATUS I2C is a trademark of Philips Corp. ________________________________________________________________ Maxim Integrated Products 1 For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800. For small orders, phone 1-800-835-8769. MAX886/MAX888 General Description MAX886/MAX888 Wireless and Satellite Handset Power-Management ICs ABSOLUTE MAXIMUM RATINGS SYNC, RESET, SCL, SDA, CVL, LBI, LBHYS, OUT0 REF, LBO, C+, C-, OUT4, IN2, IN3, IN4, IN5, ON, OFF to GND ...................................................-0.3V to +6V Continuous Power Dissipation (TA = +70°C) TQFP (derate 11.1mW/°C above +70°C) ......................889mW Operating Temperature Range. ......................... -40°C to +85°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10sec) .............................+300°C BATT, IN0, IN1 to GND...........................................-0.3V to +13V CVH to IN0................................................................-6V to +0.3V PGND, DGND to GND...........................................-0.3V to +0.3V ONSTAT to GND .....................................-0.3V to (VOUT2 + 0.3V) LX to PGND.............................................-0.3V to (VOUT0 + 0.3V) OUT1 to GND.............................................-0.3V to (VIN1 + 0.3V) OUT2 to GND.............................................-0.3V to (VIN2 + 0.3V) OUT3 to GND.............................................-0.3V to (VIN3 + 0.3V) OUT5 to GND.............................................-0.3V to (VIN5 + 0.3V) 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 (VBATT = VIN0 = VIN1 = +5.5V, GND = PGND = DGND, V OFF = VSYNC = 2.8V, VIN2 = VIN3 = VIN4 = VIN5 = +3.8V, VOUT4 = +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL BATT, IN0, IN1 Operating Voltage Range VBATT, VIN0, VIN1 VIN2, VIN3, VIN4, VIN5 IN2, IN3, IN4, IN5 Operating Voltage Range Undervoltage Lockout Supply Current, PFM Mode Supply Current, PWM Mode Supply Current, Shutdown Mode CONDITIONS MIN MAX UNITS 2.7 12 V 2.7 5.5 V VUVLOF VBATT falling VUVLOR VBATT rising 2.55 2.65 V SYNC = GND 250 600 µA fOSC = 375kHz 2 fOSC = 535kHz 3 fOSC = 670kHz 4 fOSC = 925kHz 5.5 IBATTPFM IBATTPWM ISTNBY OFF = GND 2.35 TYP TA = 0°C to +85°C 2.45 5 TA = -40°C to +85°C V mA 12 10 15 µA REFERENCE Reference Output Voltage VREF IREF = 0 TA = 0°C to +85°C 1.23 TA = -40°C to +85°C 1.225 Reference Load Regulation 1µA < IREF < 100µA Reference Supply Rejection 2.7V < VOUT0 < 3.75V 1.25 1.27 1.275 V 5 15 mV 0.2 5 mV DC-DC BUCK REGULATOR 0 (IN0, OUT0) Input Voltage Range VIN0 Output Accuracy Nominal Output Adjustment Range Output Ready Threshold 2 VOUT0 2.7 12 V IOUT0 = 0 -3 3 % MAX886 2.625 3.750 MAX888 1.527 3.027 VOUT0 = 3.75V (MAX886), VOUT0 = 2.027V (MAX888) -7.5 -5 _______________________________________________________________________________________ -3 V % of VOUT0 Wireless and Satellite Handset Power-Management ICs (VBATT = VIN0 = VIN1 = +5.5V, GND = PGND = DGND, V OFF = VSYNC = 2.8V, VIN2 = VIN3 = VIN4 = VIN5 = +3.8V, VOUT4 = +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN Output Load Regulation IOUT0 = 0.1mA to 500mA Line Regulation 3V < VIN0 < 12V -0.3 Maximum Duty Cycle VLX = 12V 100 LX Leakage Current VLX = 12V Internal Switch On-Resistance RON PFM to PWM Threshold Internal Switch Current Limit ILIMIT MAX -1.5 UNITS % 0 0.3 % 0.1 10 µA % 0.4 1 Ω 63 98 180 mA 0.6 0.9 1.2 A VIN0 = 3.8V IOUT0 TYP OSCILLATOR FREQUENCY (OUT0, OUT4) Oscillator Frequency Accuracy fOSC Table 4 TA = 0°C to +85°C -20 20 TA = -40°C to +85°C -23 23 0.8 · fOSC SYNC Range fOSC % 1.2 · fOSC kHz 12 V % LDO REGULATOR 1 (IN1, OUT1) Input Voltage Range VIN1 2.7 Output Accuracy IOUT1 = 0.1mA to 100mA -3 3 Nominal Output Adjustment Range MAX886 2.70 4.95 MAX888 1.25 3.5 VOUT1 Dropout Voltage IOUT1 = 1mA 1 IOUT1 = 100mA 90 Output Load Regulation IOUT1 = 0.1mA to 100mA -0.01 Line Regulation 3V < VIN1 < 12V, 0h code -0.1 0 100 250 Current Limit 200 V mV 0.01 %/mA 0.1 %/V mA LDO REGULATOR 2 (IN2, OUT2) Input Voltage Range VIN2 Output Accuracy 2.7 5.5 V -3 3 % MAX886 2.175 3.30 MAX888 1.527 3.027 IOUT2 = 0.1mA to 200mA Nominal Output Adjustment Range VOUT2 Output Ready Threshold VRDY2 Dropout Voltage VOUT2 = 3.3V (MAX886), VOUT2 = 1.527V (MAX888) -7.5 -5 IOUT2 = 1mA 1 IOUT2 = 200mA 90 Output Load Regulation IOUT2 = 0.1mA to 200mA Line Regulation 2.7V < VIN2 < 3.8V, 0h code Current Limit -3 200 V % of VOUT2 mV -0.005 0.002 %/mA -0.3 0.3 %/V 200 500 mA LDO REGULATOR 3 (IN3, OUT3) Input Voltage Range Output Accuracy VIN3 IOUT3 = 0.1mA to 20mA 2.7 5.5 V -3 3 % _______________________________________________________________________________________ 3 MAX886/MAX888 ELECTRICAL CHARACTERISTICS (continued) MAX886/MAX888 Wireless and Satellite Handset Power-Management ICs ELECTRICAL CHARACTERISTICS (continued) (VBATT = VIN0 = VIN1 = +5.5V, GND = PGND = DGND, V OFF = VSYNC = 2.8V, VIN2 = VIN3 = VIN4 = VIN5 = +3.8V, VOUT4 = +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 0 Nominal Output Voltage VOUT3 2.85 VIN3 = 5.5V, Table 5 V 4.65 VOUT2 Dropout Voltage IOUT3 = 1mA 1 IOUT3 = 20mA 20 Output Load Regulation IOUT3 = 0.1mA to 20mA Line Regulation 3.8V < VIN3 < 5.5V, VOUT3 = 2.85V Current Limit VOUT3 = 2.85V or 4.65V only 50 mV -0.035 0.02 %/mA -0.3 0.3 %/V 20 50 mA CHARGE-PUMP REGULATOR 4 (IN4, OUT4) Switching Frequency Output Voltage fOSC / 2 VOUT4 No load 5.10 IOUT4 = 50mA 5.25 kHz 5.41 5.21 V LDO REGULATOR 5 (IN5, OUT5) Input Voltage Range VIN5 Output Accuracy Nominal Output Adjustment Range 2.7 5.5 V -3 3 % MAX886 2.175 3.300 MAX888 1.25 3.50 IOUT5 = 0.1mA to 100mA VOUT5 Dropout Voltage IOUT5 = 1mA 1 IOUT5 = 100mA 72 200 V mV Output Load Regulation IOUT5 = 0.1mA to 100mA -0.01 0.01 %/mA Line Regulation 2.7V < VIN5 < 3.8V, 0h code -0.3 0.3 %/V Current Limit 100 250 mA LOW-BATTERY COMPARATOR LBI Input Current VLBI = 1.23V -0.2 VREF 15mV LBI Threshold LBI Propagation Delay VLBI = step from 1.23V to 1.27V LBO/LBHYS Output Low Voltage V LBO = ILBHYS = 1mA, VLBI = VREF - 15mV LBO/LBHYS Leakage Current V LBO = VLBHYS = 12V, VLBI = VREF + 15mV VREF 0.2 µA VREF + 15mV V 10 -0.2 µs 0.5 V 0.2 µA RESET AND START-UP TIMER Reset Timeout Period 56 75 94 ms Start-Up Timeout Period 28 37 47 ms LOGIC AND CONTROL INPUTS ON Input Voltage 4 VIL VIH 0.4 1.2 _______________________________________________________________________________________ V Wireless and Satellite Handset Power-Management ICs (VBATT = VIN0 = VIN1 = +5.5V, GND = PGND = DGND, V OFF = VSYNC = 2.8V, VIN2 = VIN3 = VIN4 = VIN5 = +3.8V, VOUT4 = +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL ON Input Current SYNC Input Voltage SYNC Input Current CONDITIONS MIN TYP MAX IIL V ON = 0 -16 -40 IIH 1.2V < V ON < VOUT2 -5 -10 VIL 0.8 VIH ISYNC 2.0 0 < VSYNC < VOUT2 0.25 UNITS µA V 1 µA 0.5 V ONSTAT OUTPUT ONSTAT Output Voltage VONSTATL IONSTAT = 1mA ONSTAT Output Voltage VONSTATH IONSTAT = 0 VOUT2 0.5 V RESET OUTPUT Output Low Voltage V RESETL I RESET = 1mA Output High Voltage V RESETH I RESET = 0, internal 10kΩ pull-up resistor to OUT2 0.5 VOUT2 0.5 V V THERMAL SHUTDOWN Threshold Temperature I2C-COMPATIBLE 160 °C SERIAL INTERFACE SCL Clock Frequency fSCL SCL Low Period tLOW 1.3 µs SCL High Period tHIGH 0.6 µs tDSU 100 tDHOLD 0 Data Set-Up Time Data Hold Time OFF, SDA, SCL Input Voltage OFF, SDA, SCL Input Current SDA Output Low Voltage LBO, LBHYS Leakage Current 400 VIL IILH ns 0.9 0.6 VIH 1.4 0 < VILH < VOUT2 1 ISDA = 3mA 0.4 ISDA = 6mA 0.6 V LBO = VLBHYST = 12V, VLBI = VREF + 15mV -0.2 kHz 0.2 µs V µA V µA Note 1: Specifications to -40°C are guaranteed by design, not production tested. _______________________________________________________________________________________ 5 MAX886/MAX888 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (Circuit of Figure 2, REG0 to REG5 outputs at POR states, VOUT0 = 3.75V, VOUT4 = 5.25V, VOUT1 = VOUT2 = VOUT3 = VOUT5 = 3.3V, TA = +25°C, unless otherwise noted.) MAX886 REG0 EFFICIENCY vs. LOAD CURRENT (VBATT = 5.4V) PFM, 375kHz 90 EFFICIENCY (%) 70 PWM, 925kHz 80 PWM, 375kHz 70 PWM, 925kHz 60 60 50 50 8 PWM, 925kHz 7 6 5 4 3 PWM, 375kHz 2 1 1,000 1 10 MAX888 REG0 EFFICIENCY vs. LOAD CURRENT (VBATT = 4.2V) PFM, 375kHz 90 PFM, 925kHz PFM, 375kHz 90 EFFICIENCY (%) EFFICIENCY (%) 3 4 5 80 PWM, 925kHz PWM, 375kHz 60 6 7 9 10 11 12 MAX888 NO LOAD BATTERY CURRENT vs. BATTERY VOLTAGE 7 6 PWM, 375kHz 80 PWM, 925kHz 70 5 PWM, 925kHz 4 3 PWM, 375kHz 2 60 1 50 10 100 3 4 5 6 REG4 OUTPUT VOLTAGE vs. LOAD CURRENT SHUTDOWN CURRENT vs. BATTERY VOLTAGE 5.24 5.22 5.20 5.18 5.16 20 5.14 0 5.12 20 40 60 80 100 120 140 160 180 200 LOAD CURRENT (mA) 10 R1, R2, R3 NOT CONNECTED 9 SHUTDOWN CURRENT (µA) REG2 5.26 OUTPUT VOLTAGE (V) 60 VIN4 = 3.75V MAX886/88-08 5.28 MAX886/88-07 REG5 0 2 1,000 DROPOUT VOLTAGE vs. LOAD CURRENT REG1 40 100 BATTERY VOLTAGE (V) 100 REG3 10 LOAD CURRENT (mA) VIN1 = VIN2 = VIN5 = 3.3V VIN3 = 2.85V 80 1 LOAD CURRENT (mA) 140 120 1,000 PFM MODE 0 50 1 6 8 BATTERY VOLTAGE (V) 100 PFM, 925kHz 70 2 1,000 MAX888 REG0 EFFICIENCY vs. LOAD CURRENT (VBATT = 2.7V) MAX886/88-04 100 100 LOAD CURRENT (mA) MAX886/88-06 100 BATTERY CURRENT (mA) 10 LOAD CURRENT (mA) MAX886/88-05 1 PFM MODE 0 MAX886/88-09 EFFICIENCY (%) PWM, 375kHz 9 BATTERY CURRENT (mA) PFM, 925kHz PFM, 375kHz 80 10 MAX886/88-02 PFM, 925kHz 90 100 MAX886/88-01 100 MAX886 NO-LOAD BATTERY CURRENT vs. BATTERY VOLTAGE MAX886/88-03 MAX886 REG0 EFFICIENCY vs. LOAD CURRENT (VBATT = 8.4V) DROPOUT VOLTAGE (mV) MAX886/MAX888 Wireless and Satellite Handset Power-Management ICs 8 7 6 5 4 3 2 1 0 0 20 40 60 LOAD CURRENT (mA) 80 100 2 3 4 5 6 7 8 9 BATTERY VOLTAGE (V) _______________________________________________________________________________________ 10 11 12 Wireless and Satellite Handset Power-Management ICs REG1 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY REG2 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY 60 VOUT2 = 3.3V IOUT2 = 20mA COUT2 = 2.2µF 60 VON (2V/div) 50 PSRR (dB) 50 PSRR (dB) MAX886/88-12 MAX886/88-11 VOUT1 = 3.3V IOUT1 = 10mA COUT1 = 2.2µF REG0 TURN-ON DELAY 70 MAX886/88-10 70 40 30 40 30 20 20 10 10 0 VOUT0 (2V/div) 0 0.01 0.1 1 10 100 1,000 0.01 FREQUENCY (kHz) 0.1 1 10 100 1,000 400µs/div IOUT0 = 20mA FREQUENCY (kHz) REG0 LINE-TRANSIENT RESPONSE (PWM MODE) REG0 LINE-TRANSIENT RESPONSE (PFM MODE) MAX886/88-13 REG2 LINE-TRANSIENT RESPONSE (IN2 CONNECTED TO OUT0) MAX886/88-14 MAX886/88-15 VBATT (500mV/div) VBATT (500mV/div) VBATT (500mV/div) VOUT0 (100mV/div) VOUT0 (100mV/div) VOUT2 (100mV/div) 400µs/div VBATT = 7V TO 8V, IOUT0 = 500mA, VOUT0 = 3.75V, AC-COUPLED 400µs/div VBATT = 7V TO 8V, IOUT0 = 5mA, VOUT0 = 3.75V, AC-COUPLED REG0 LOAD-TRANSIENT RESPONSE (PWM MODE) 400µs/div VBATT = 7V TO 8V, IOUT2 = 5mA, VOUT2 = 3.3V, AC-COUPLED REG0 LOAD-TRANSIENT RESPONSE (PFM MODE) MAX886/88-16 REG2 LOAD-TRANSIENT RESPONSE (IN2 CONNECTED TO BATT) MAX886/88-17 MAX886/88-18 IOUT0 (200mA/div) IOUT0 (200mA/div) IOUT2 (200mA/div) VOUT0 (100mV/div) VOUT0 (100mV/div) VOUT2 (100mV/div) 400µs/div VBATT = 5.4V, IOUT0 = 0 TO 500mA, VOUT0 = 3.75V, AC-COUPLED 400µs/div VBATT = 5.4V, IOUT0 = 0 TO 500mA, VOUT0 = 3.75V, AC-COUPLED 400µs/div VBATT = VIN2 = 5.4V, IOUT2 = 0 TO 200mA, VOUT2 = 3.3V, AC-COUPLED _______________________________________________________________________________________ 7 MAX886/MAX888 Typical Operating Characteristics (continued) (Circuit of Figure 2, REG0 to REG5 outputs at POR states, VOUT0 = 3.75V, VOUT4 = 5.25V, VOUT1 = VOUT2 = VOUT3 = VOUT5 = 3.3V, TA = +25°C, unless otherwise noted.) Wireless and Satellite Handset Power-Management ICs MAX886/MAX888 Pin Description 8 PIN NAME FUNCTION 1 LX 2 PGND Power Ground 3 OUT0 Switching Regulator 0 Output. Bypass with a 10µF, low-ESR capacitor to PGND. Up to 500mA is available from OUT0. 4 CVL Low-Side Drive Bypass. Bypass with a 1µF capacitor to GND. 5 REF Reference Output. Bypass with a 0.22µF capacitor to GND. REF can source up to 100µA. 6 GND Ground 7 BATT Supply Voltage Input. Bypass with a 0.1µF and a 10µF capacitor to PGND as close to BATT as possible. 8 OUT4 Charge-Pump Regulator 4 Output. Bypass with a 10µF, low-ESR capacitor to DGND. 9 C+ Charge-Pump Capacitor Positive Connection 10 IN4 Regulator 4 Power-Supply Input 11 C- Charge-Pump Capacitor Negative Connection 12 DGND 13 LBI Low-Battery Detector Input. LBO goes low when VLBI drops below VREF. Connect LBI to the center of a resistor voltage divider between BATT and GND. 14 LBHYS Low-Battery Detector Hysteresis Control. An open-drain output to set the hysteresis of the Low-Battery Detector Comparator. 15 LBO 16 RESET 17 IN2 18 OUT2 Linear Regulator 2 Output. Bypass with a 2.2µF, low-ESR capacitor to GND. Up to 200mA is available from OUT2. The reset circuit monitors this voltage. 19 OUT3 Linear Regulator 3 Output. Bypass with a 1µF, low-ESR capacitor to GND. Up to 20mA is available from OUT3. 20 IN3 Regulator 3 Power-Supply Input 21 IN5 Regulator 5 Power-Supply Input 22 OUT5 23 IN1 Inductor Input. Drain of the internal p-channel MOSFET. Digital Ground Low-Battery Output. Open-drain output of the Low-Battery Detector Comparator. LBO is high impedance when device is shutdown or VLBI > VREF. V LBO is low when VLBI < VREF. Typically, connect a 200kΩ pullup resistor between LBO and OUT2. Reset Output. RESET remains low during initial power-up for 75ms after OUT2 is ready. RESET has an internal 10kΩ pull-up resistor connected to OUT2. RESET is valid for VBATT down to 1V. Linear Regulator 2 Power-Supply Input Linear Regulator 5 Output. Bypass with a 1µF, low-ESR capacitor to GND. Up to 100mA is available from OUT5. Regulator 1 Power-Supply Input _______________________________________________________________________________________ Wireless and Satellite Handset Power-Management ICs PIN NAME FUNCTION 24 OUT1 Linear Regulator 1 Output. Bypass with a 2.2µF, low-ESR capacitor to GND. Up to 100mA is available from OUT1. 25 OFF Power-Off Input. Drive OFF high before the start-up timer has expired in order to keep the IC powered on. Drive OFF low to shut down the IC. OFF has an internal 100kΩ pull-down resistor to GND. 26 ON Power-On Input. Pulse the ON pin low to turn on the IC. ON has an internal 16µA pull-up. 27 ONSTAT 28 SDA Serial Interface Data Input 29 SCL Serial Interface Clock Input 30 SYNC 31 CVH High-Side Drive Bypass Input. Bypass CVH with a 0.1µF capacitor connected to IN0. 32 IN0 Regulator 0 Power-Supply Input. Connect to BATT. Source of the internal p-channel MOSFET. ON Status Output. Push/pull logic output indicating the state of the ON input. The logic state of this pin follows the logic state of the ON pin. The logic high output voltage is the output voltage of OUT2. Sync Input. Drive SYNC with a logic-level square wave to synchronize the internal oscillator. The capture range for external clock is ±20% of the selected internal oscillator frequency. Drive SYNC low for more than 10µs to force low-power PFM mode (standby mode). Drive SYNC high to force PWM mode. A tLOW B tHIGH C D E F G H I J K L M SCL SDA tSU:STA tHD:STA A = START CONDITION B = MSB OF ADDRESS CLOCKED INTO SLAVE C = LSB OF ADDRESS CLOCKED INTO SLAVE D = R/W BIT CLOCKED INTO SLAVE E = SLAVE PULLS SMBDATA LINE LOW tSU:DAT tHD:DAT F = ACKNOWLEDGE BIT CLOCKED INTO MASTER G = MSB OF DATA CLOCKED INTO SLAVE (OP/SUS BIT) H = LSB OF DATA CLOCKED INTO SLAVE I = SLAVE PULLS SMBDATA LINE LOW tSU:STO tBUF J = ACKNOWLEDGE CLOCKED INTO MASTER K = ACKNOWLEDGE CLOCK PULSE L = STOP CONDITION, DATA EXECUTED BY SLAVE M = NEW START CONDITION Figure 1. I2C-Compatible Serial-Interface Timing Diagram _______________________________________________________________________________________ 9 MAX886/MAX888 Pin Description (continued) MAX886/MAX888 Wireless and Satellite Handset Power-Management ICs IN 4V TO 12V L1 10µH C2 0.1µF C1 10µF LX BATT PGND IN0 R1 1.1M C4 0.1µF IN1 C11 10µF D1 MBR0520L OUT0 UP TO 500mA OUT0 CVH IN2 LBI IN4 R2 562k MAX886 IN5 LBHYS OUT1 R3 23.3k GND C5 0.22µF C3 1µF OUT1 C7 UP TO 100mA 2.2µF OUT2 R5 200k REF OUT2 C8 UP TO 200mA 2.2µF LBO CVL RESET C+ OUT3 C6 0.22µF OUT3 C9 UP TO 20mA 1µF COUT4 OUT4 C12 5.25V UP TO 100mA 10µF SCL IN3 SDA OUT5 ON OUT5 C10 UP TO 100mA 1µF OFF ONSTAT SYNC DGND Figure 2a. Typical 2 Li+ or 5 to 6 Ni-Cell Application Circuit (MAX886) 10 ______________________________________________________________________________________ Wireless and Satellite Handset Power-Management ICs MAX886/MAX888 IN 2.7V TO 5.5V L1 10µH C2 0.1µF C1 10µF LX BATT PGND IN0 R1 619k C4 0.1µF IN1 C11 10µF D1 MBR0520L OUT0 UP TO 500mA OUT0 CVH IN2 LBI IN4 R2 562k IN5 MAX888 LBHYS OUT1 R3 47.6k GND C5 0.22µF C3 1µF OUT1 C7 UP TO 100mA 2.2µF OUT2 R5 200k REF OUT2 C8 UP TO 200mA 2.2µF LBO CVL RESET C+ OUT3 C6 0.22µF COUT4 OUT3 C9 UP TO 20mA 1µF OUT4 C12 5.25V UP TO 100mA 10µF SCL IN3 SDA OUT5 ON OUT5 C10 UP TO 100mA 1µF OFF ONSTAT SYNC DGND Figure 2b. Typical 1 Li+ or 3 to 4 Ni-Cell Application Circuit (MAX888) ______________________________________________________________________________________ 11 MAX886/MAX888 Wireless and Satellite Handset Power-Management ICs Detailed Description The MAX886/MAX888 contain one high-efficiency, stepdown DC-DC converter, four low-dropout linear regulators, and one regulated charge pump. The output voltages of the switching regulator and the linear regulators are software-programmable through the serial interface. The regulated charge-pump output is factory set at 5.25V. The devices also include reset and start-up timers and a low-battery detect comparator (Figure 3). 500mA DC-DC Buck Regulator 0 Regulator 0 is a low-noise, step-down, synchronous DC-DC converter that can source a minimum of 500mA. High operating frequency (up to 925kHz) minimizes output voltage ripple and reduces the size and cost of external components. Guaranteed 100% dutycycle operation provides the lowest possible dropout voltage, extending the useful life of the battery supply. 5 ON1 SDA SCL DAC1 LOGIC DECODER ON2 DAC2 ON2 DAC3 DAC5 ON5 LINEAR REG1 IN1 OUT1 LINEAR REG2 IN2 OUT2 LINEAR REG3 IN3 OUT3 LINEAR REG5 IN5 OUT5 CVH CVL IN0 BATT LX DAC0 ON0 SYNC OUT2 + SWITCHING REGULATOR PGND IN4 OSCILLATOR 10k ON4 RESET ON OFF OUT0 RESET AND START UP TIMER REG4 CHARGE PUMP REGULATOR OUT4 C+ C- ONSTAT LBI LBO REF REF LBHYS DGND GND Figure 3. Functional Diagram 12 ______________________________________________________________________________________ Wireless and Satellite Handset Power-Management ICs Sync Mode The SYNC input allows the MAX886/MAX888 to synchronize with an external clock applied to SYNC, ensuring that switching harmonics are kept away from sensitive IF bands. The SYNC detector triggers on SYNC’s falling edge. PWM Mode Regulator 0 is in PWM mode when SYNC is connected to CVL or driven to a logic-high voltage. Two internal switches operate at a preset frequency even when there is no load. The P-channel MOSFET turns on to charge the inductor until the error comparator or current-limit comparator turns it off. The N-channel MOSFET then turns on to discharge the inductor. To prevent the output from soaring with no load in PWM mode, the N-channel switch stays on long enough to allow the inductor current to go negative. Once the N-channel switch turns off, the voltage at LX rises (rings) until the next cycle when the P-channel switch turns on again. As the load increases and the inductor enters continuous conduction, ringing is no longer present and the LX waveform looks like a square wave whose duty cycle depends on the input and output voltages. As the input voltage approaches the same level as the output voltage, the P-channel switch stays on 100% of the time, providing the lowest possible dropout. PFM Mode Regulator 0 operates in PFM mode when SYNC is driven to a logic low voltage or connected to GND. When V OUT0 drops below the regulation threshold, the Pchannel switch turns on to charge the inductor until the error comparator or current-limit comparator turns it off. At light loads, the N-channel then turns on to discharge the inductor until the current in the inductor reaches zero. In PFM mode, the inductor current does not go negative to discharge the output. At no-load there is a long period between pulses of inductor current. As the load current increases, the period between pulses becomes shorter until the pulses become continuous. At load currents above this point, Regulator 0 automatically switches to PWM mode, and the VLX waveform looks like a square wave whose duty cycle depends on the input and output voltages. As the input voltage approaches the same level as the output voltage, the P-channel switch stays on 100% of the time, providing the lowest possible dropout. It is typically more efficient to use the PFM mode when the load current is less than 100mA. 100mA LDO Regulator 1 Regulator 1, a low-dropout linear regulator, sources a minimum of 100mA and operates from voltages at IN1 of up to 12V. The serial interface programs VOUT1 from 2.7V to 4.95V in 75mV steps for the MAX886 (Tables 1 and 2), or from 1.25V to 3.50V in 150mV steps for the MAX888 (Tables 1 and 3). IN1 may be powered from the battery, OUT0, or any other voltage source. 200mA LDO Regulator 2 Regulator 2, a low-dropout linear regulator, sources a minimum of 200mA. The serial interface programs VOUT2 from 2.175V to 3.3V in 75mV steps for the MAX886 (Tables 1 and 2), or from 1.527V to 3.027V in 100mV steps for the MAX888 (Tables 1 and 3). IN2 may be powered from the battery, OUT0, or any other voltage source less than 5.5V. 20mA LDO Regulator 3 Regulator 3, a low-dropout linear regulator, sources a minimum of 20mA. The serial interface programs VOUT3 to one of four different output voltages: 0V, 2.85V, 4.65V, or VOUT2 (Tables 1 and 5). Although this is a generalpurpose output, OUT3 is intended for the SIM supply. IN3 may be powered from OUT4 or from any regulated 5V supply. When programmed to 0V or VOUT2, OUT3 is either actively discharged to GND (for 0V mode) or connected to OUT2 (for VOUT2), and Regulator 3 is disabled to conserve power. 100mA Charge-Pump Regulator 4 Regulator 4, a regulated charge pump, generates 5.25V and delivers up to 100mA. An oscillator synchronized to the PWM clock regulates OUT4 to minimize noise. It operates at one-half the frequency of the PWM oscillator to ensure 50% duty-cycle outputs. IN4 may be powered from the battery, OUT0, or any other voltage source less than 5.5V. To save space and cost, use a small ceramic flying capacitor. See Table 6 for recommended flying capacitor values. ______________________________________________________________________________________ 13 MAX886/MAX888 The serial interface programs V OUT0 from 2.625V to 3.75V in 75mV steps for the MAX886 (Tables 1 and 2), or from 1.527V to 3.027V in 100mV steps for the MAX888 (Tables 1 and 3). Regulator 0 operates in one of four preset frequencies, from 375kHz to 925kHz, programmable through the serial interface (Table 4). For the device to power up properly, VIN0 must be high enough for REG0 to get into regulation. For the MAX886, Regulator 0’s default voltage is 3.75V. Since the rest of the regulators do not power up until Regulator 0 is ready, VIN0 must be greater than approximately 4V for the device to power up properly. The Regulator 0 default voltage for the MAX888 is 2.027V, so the minimum VIN0 required to start up is limited by the minimum operating voltage range (2.7V). After power-up, the device operates until VBATT drops below V UVLOF (undervoltage lockout falling threshold). MAX886/MAX888 Wireless and Satellite Handset Power-Management ICs 100mA LDO Regulator 5 Control Data Byte Regulator 5, a low-dropout linear regulator, can source a minimum of 100mA. The output voltage is programmable from 2.175V to 3.3V in 75mV steps for the MAX886 (Tables 1 and 2), or 1.25V to 3.50V in 150mV steps for the MAX888 (Tables 1 and 3). IN5 may be powered from the battery, OUT0, or any other voltage source less than 5.5V. The control byte is eight bits long (four address bits, four data bits). Each regulator has a DAC that sets the output regulation voltage. Control codes are summarized in Table 1. Table 1. Control Data Byte ADDRESS DATA FUNCTION A3 MSB A2 A1 A0 OUT0 Output Voltage 0 0 0 0 DAC0 OUT1 Output Voltage 0 0 0 1 DAC1 OUT2 Output Voltage 0 0 1 0 DAC2 OUT3 Output Voltage, fOSC 0 0 1 1 OUT5 Output Voltage 0 1 0 0 OUT1, 2, 4, 5 On/Off Control 0 1 0 1 ON5 ON4 ON2 ON1 OUT0 On/Off Control 0 1 1 0 X X X ON0 Not Available 0 1 1 1 X X X X Not Available 1 X X X X X X X D3 D2 D0 LSB D1 DAC3 fOSC DAC5 Table 2. MAX886 Output Voltage Settings REGULATOR OUTPUT VOLTAGE (V) DACX DATA OUT5 OUT2 OUT1 OUT0 D3 D2 D1 D0 2.175 2.175 2.70 2.625 0 0 0 0 2.250 2.250 2.85 2.700 0 0 0 1 2.325 2.325 3.00 2.775 0 0 1 0 2.400 2.400 3.15 2.850 0 0 1 1 2.475 2.475 3.30 2.925 0 1 0 0 2.550 2.550 3.45 3.000 0 1 0 1 2.625 2.625 3.60 3.075 0 1 1 0 2.700 2.700 3.75 3.150 0 1 1 1 2.775 2.775 3.90 3.225 1 0 0 0 2.850 2.850 4.05 3.300 1 0 0 1 2.925 2.925 4.20 3.375 1 0 1 0 3.000 3.000 4.35 3.450 1 0 1 1 3.075 3.075 4.50 3.525 1 1 0 0 3.150 3.150 4.65 3.600 1 1 0 1 3.225 3.225 4.80 3.675 1 1 1 0 3.300 3.300 4.95 3.750 1 1 1 1 Note: The output voltage of each regulator can be set independently. The POR states are in boldface. 14 ______________________________________________________________________________________ Wireless and Satellite Handset Power-Management ICs MAX886/MAX888 Table 3. MAX888 Output Voltage Settings REGULATOR OUTPUT VOLTAGE (V) DACX DATA OUT5 OUT2 OUT1 OUT0 D3 D2 D1 D0 1.25 1.527 1.25 1.527 0 0 0 0 1.40 1.627 1.40 1.627 0 0 0 1 1.55 1.727 1.55 1.727 0 0 1 0 1.70 1.827 1.70 1.827 0 0 1 1 1.85 1.927 1.85 1.927 0 1 0 0 2.00 2.027 2.00 2.027 0 1 0 1 2.15 2.127 2.15 2.127 0 1 1 0 2.30 2.227 2.30 2.227 0 1 1 1 2.45 2.327 2.45 2.327 1 0 0 0 2.60 2.427 2.60 2.427 1 0 0 1 2.75 2.527 2.75 2.527 1 0 1 0 2.90 2.627 2.90 2.627 1 0 1 1 3.05 2.727 3.05 2.727 1 1 0 0 3.20 2.827 3.20 2.827 1 1 0 1 3.35 2.927 3.35 2.927 1 1 1 0 3.50 3.027 3.50 3.027 1 1 1 1 Note: The output voltage of each regulator can be set independently. The POR states are in boldface. Low-Battery Detector Table 4. Oscillator Frequency Setting ADDRESS 03h DATA fOSC (kHz) D3 D2 D1 D0 375 X X 0 0 535 X X 0 1 670 X X 1 0 925 X X 1 1 Note: The POR states are in boldface. Table 5. OUT3 Output Voltage Setting A low-battery comparator detects low-battery conditions. The trip threshold is internally set to VREF (1.25V typ). LBHYS sets the hysteresis with external resistors. LBO and LBHYS have open-drain outputs. The externally set low-battery threshold must be higher than the UVLOF threshold (2.45V typical). Set the threshold and hysteresis by connecting resistors R1 (between BATT and LBI), R2 (between LBI and LBHYS), and R3 (LBHYS and GND) (Figure 2). After choosing the upper and lower thresholds, calculate the resistor values as follows: 1) Choose a value for R1. Typical values range from 500kΩ to 1.5MΩ. 2) Calculate R2: ADDRESS 03h DATA D3 D2 D1 D0 0V (REG3 Off) 0 0 X X 2.85V 0 1 X X 4.65V 1 0 X X VOUT2 (REG3 Off) 1 1 X X Note: The POR states are in boldface. R2 = 3) Calculate R3: R3 = ( R1 VTHR – 1 VREF R2 VTHF − VREF ) − R1 ⋅ VREF VREF − VTHF ______________________________________________________________________________________ 15 MAX886/MAX888 Wireless and Satellite Handset Power-Management ICs ONSTAT Output For example: VREF = 1.25V VTHF = falling threshold = 2.52V VHYS = hysteresis = 0.1V VTHR = rising threshold = VTHF + VHYS = 2.62V R1 = 619kΩ (1%) R2 = 562kΩ (1%) R3 = 47.6kΩ (1%) Power-On Sequence (Including RESET and Start-Up Timers) Drive ON low to begin the power-up sequence. To reduce overall system cost and complexity, the MAX886/MAX888 incorporate RESET and start-up timers with the power-on sequence. The MAX886/MAX888 turn on the reference when ON goes low. Once the reference is fully powered up, if the input voltage exceeds the internal undervoltage-lockout threshold (UVLOR), Regulator 0 turns on. Once OUT0 is in regulation, OUT2 and OUT4 turn on. Once OUT2 is in regulation, OUT1 and OUT5 turn on and the 75ms reset timer begins. RESET remains low from the time OUT2 is valid until the reset timer times out. After the reset period expires, a 50ms start-up timer begins. The MAX886/MAX888 shut down if the external logic or controller fails to drive OFF high before the start-up timer expires. Drive OFF high to continue operation. Driving OFF low turns off the IC. There is no required sequence to power off any regulator after the device has turned on. Regulators can be powered off selectively by sending the correct code through the serial interface (Table 1). ONSTAT is a logic output that follows ON. Connect ONSTAT to the external logic or controller to sense when the ON pin has been brought low to request shutdown. This allows easy implementation of a one-button on/off control scheme (Figure 4). Thermal Overload Protection An internal thermal sensor shuts the MAX886/MAX888 down when the maximum temperature limit is exceeded (160°C typical). I2C-Compatible Serial Interface I 2 C-compatible Use an serial interface to turn the MAX886/MAX888 on and off, as well as control each regulator’s output voltage and program the DC-DC converter and charge pump’s oscillator frequency. Use standard I2C-compatible receive-byte commands to program the IC. This part is always a slave to the bus master. The chip address is 1001 111. POR State The power-on reset state of all the DAC and frequency registers is 0Fh, except for DAC1 which is 04h. The power-on reset state of the ONX bits is 1 (Table 1). The power-on voltage for each regulator is shown in bold in Tables 2, 3, and 5. Applications Information Inductor Selection The essential parameters for inductor selection are inductance and current rating. The MAX886/MAX888 operate with a wide range of inductance values. In many applications, values between 10µH and 68µH take best advantage of the controller’s high switching frequency. Calculate the minimum inductance value using the simplified equation: ( ) L MIN = OUT2 MAX886 MAX888 10k RESET ON ONSTAT OFF µC (I 4 VBATT MAX − VOUT0 PEAK ( ) ⋅ fOSC ⋅ VBATT / VOUT0 ) where IPEAK is the peak inductor current (0.9A) and fOSC is the switching frequency. For example, for a 6V battery voltage, a desired VOUT0 is 3.3V, the oscillator frequency is 375kHz, and 15µH is the minimum inductance required. Diode Selection Figure 4. One-Button On/Off Control with ONSTAT 16 The MAX886/MAX888’s high switching frequency demands a high-speed rectifier. Schottky diodes, such as the 1N5817–1N5822 family or surface-mount MBR0520L series are recommended. Ultra-high-speed rectifiers with reverse recovery times around 50ns or ______________________________________________________________________________________ Wireless and Satellite Handset Power-Management ICs Capacitor Selection Choose filter capacitors to service input and output peak currents with acceptable voltage ripple. The capacitor’s equivalent series resistance (ESR) is a major contributor to ripple; therefore, low-ESR capacitors are recommended for OUT1–OUT5. A tantalum capacitor is recommended for OUT0 (refer to Figures 2a and 2b, and Table 6). The input filter capacitor reduces peak currents drawn from the power source, and reduces noise and voltage ripple on the input, which are caused by the circuit’s switching action. Since the current from the battery is interrupted each time the PMOS switch opens, pay special attention to the ripple current rating of the input filter capacitor and use a low-ESR capacitor. Choose input capacitors with working voltage ratings higher than the maximum input voltage. Input capacitors prevent spikes and ringing on the power source from obscuring the current-feedback signal and causing jitter. Bypass REF with 0.22µF to GND. The capacitor should be placed within 0.2 inches of the IC, next to REF, with a direct trace to GND. Table 6. OUT0 and OUT4 Regulator Component Recommendations fOSC (kHz) C11 (µF) L1 (µH) C6 (µF) C12 (µF) 925 10 10 0.22 10 670 15 15 0.33 15 535 22 22 0.47 22 375 33 33 1 33 Table 7. Component Suppliers PHONE FAX AVX COMPANY 803-946-0690 803-626-3123 Coilcraft 847-639-6400 847-639-1469 Coiltronics 516-241-7876 516-241-9339 Dale 605-668-4131 605-665-1627 Internal Rectifier 310-322-3331 310-322-3332 Motorola 602-303-5454 602-994-6430 Sanyo 619-661-6835 619-661-1055 Sprague 408-988-8000 408-970-3950 Sumida 847-956-0666 847-956-0702 Layout Considerations High-frequency switching regulators are sensitive to PC board layout. Poor layout introduces switching noise into the current and voltage-feedback signals, resulting in jitter, instability, or degraded performance. Place the anode of the Schottky diode and the ground pins of the input and output capacitors close together, and route them to a common “star-ground” point. Place components and route ground paths so as to prevent high currents from causing large voltage gradients between the ground pin of the output filter capacitor, the controller IC, and the reference bypass capacitor. Keep the extra copper on the component and solder sides of the PC board rather than etching it away, and connect it to ground for use as a pseudo-ground plane. Refer to the MAX886/MAX888 evaluation kit for a two-layer PC board layout example. ______________________________________________________________________________________ 17 MAX886/MAX888 faster, such as the MUR series, are acceptable. Ensure that the diode’s peak current rating exceeds the peak current (1A), and that its breakdown voltage exceeds VBATT. Schottky diodes are preferred for heavy loads due to their low forward voltage, especially in low-voltage applications. Wireless and Satellite Handset Power-Management ICs IN0 CVH SYNC SCL SDA ONSTAT ON OFF MAX886/MAX888 Pin Configuration 32 31 30 29 28 27 26 25 TOP VIEW LX 1 24 OUT1 PGND 2 23 IN1 OUT0 3 22 OUT5 CVL 4 REF 21 IN5 MAX886 MAX888 5 20 IN3 9 10 11 12 13 14 15 16 LBO RESET 17 IN2 LBI 8 LBHYS OUT4 DGND 18 OUT2 C- 19 OUT3 IN4 6 7 C+ GND BATT Chip Information TRANSISTOR COUNT: 2042 18 ______________________________________________________________________________________ Wireless and Satellite Handset Power-Management ICs TQFPPO.EPS ______________________________________________________________________________________ 19 MAX886/MAX888 Package Information MAX886/MAX888 Wireless and Satellite Handset Power-Management ICs NOTES 20 ______________________________________________________________________________________