SC1460

5mA CAPLESS TM CHARGE PUMP SC1460 PRELIMINARY - July 6, 1999 TEL:805-498-2111 FAX:805-498-3804 WEB:http://www.semtech.com DESCRIPTION The SC1460 is a versatile charge pump designed for use in battery operated power supply applications requiring up to 5mA. It enables a simple low current boost circuit to be implemented without the costly inductors or capacitors associated with regular switching circuits. Features include internal MOSFETs, control circuitry and charge pump capacitor, requiring only two external capacitors for a total solution. With a very high operating frequency (8MHz free running at 2.5V in typically), the SC1460 does not require large input or output capacitors, and therefore uses very little board space. Two versions of the SC1460 are available: the -3.3 produces a regulated 3.3V output from 2.5V in, and the -5.0 produces a regulated 5V output from 3.3V in. It is supplied in the popular 3 lead, SOT-23 package. FEATURES • Small size - SOT-23 package • 4% voltage accuracy • Typical 100uA quiescent current APPLICATIONS • Handheld Power Supplies • PDA Power Supplies • Notebook Power Supplies • Peripheral Card Supplies • Industrial Power Supplies • High Density DC/DC Conversion ORDERING INFORMATION BLOCK DIAGRAM DEVICE (1)(2) PACKAGE SOT-23 SC1460CSK-X.X Notes: (1) Where X.X denotes voltage options. Available voltages are: 3.3V and 5.0V. (2) Add suffix ‘TR’ for tape and reel. ABSOLUTE MAXIMUM RATINGS Parameter Supply Voltage Output Voltage Thermal Resistance Junction to Ambient Operating Temperature Symbol VIN VO θJA TA TJ TSTG TL Maximum -0.3 to + 4 -0.3 to +6.0 410 0 to +70 0 to 125 -65 to +150 300 Units V V °C/W °C °C °C °C PIN CONFIGURATION (Top View) Temperature Range Storage Temperature Lead Temperature (Soldering) 10 seconds 3 Lead SOT-23 1 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 5mA CAPLESS TM CHARGE PUMP SC1460 PRELIMINARY - July 6, 1999 ELECTRICAL CHARACTERISTICS Unless specified: VIN = 3.3V (-5.0 parts), VIN = 2.5V (-3.3 parts), 0 ≤ IO ≤ 4mA, CIN = 0.22uF, COUT = 47nF, TA = 25°C. Values in bold apply over full operating temperature range Parameter Input Supply Voltage Input Supply Current Output Voltage Symbol VIN IIN VO Conditions MIN 2.25 TYP MAX 3.63 Units V µA % % mV mA % MHz IO = 0mA VIN = 2.5 V SC1460CSK - 3.3, VIN = 2.5V SC1460CSK - 5.0, VIN = 3.3V -4 4 100 1.32 x VIN 1.515 X VIN 50 4 5 56 8 8.75 100 150 4 4 Output Ripple (pk-pk) Output Current Efficiency Oscillator Frequency VR IO η OSC IO = 4mA, COUT = 47nF IO = 4mA SC1460CSK - 3.3, VIN = 2.5V SC1460CSK - 5.0, VIN = 3.3V 50 Time to Regulation at Turn-On tON Power Up with IO = 4mA µs APPLICATION CIRCUIT VIN 2 U 1 SC1460 VIN VO 1 VO GND C in 0.22uF 3 C out 47nF 2 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 5mA CAPLESS TM CHARGE PUMP SC1460 PRELIMINARY - July 6, 1999 Typical Eff. vs. Vo @25 Deg. C. 60 5 4.5 Efficiency (%) 55 Vo (V) 4 3.5 3 2.5 5 2 0 Vin = 3.60V Vin = 3.30V Vin = 2.50V Vin = 2.25V Typical Vo vs. Io @25 Deg. C. 50 Io = 4 mA Io = 5 mA Io = 6 mA 45 2.5 3 3.5 Vo (V) 4 4.5 1 2 3 Io (mA) 4 5 6 Typical Eff. vs. Vin @25 Deg. C. 60 16 14 12 Efficiency (%) 55 Iin (mA) 10 8 6 4 2 0 2 2.5 3 Vin (V) 3.5 4 2 Typical Iin vs. Vin @25 Deg. C. 50 Io = 4mA Io = 5mA Io = 6mA Io = 6 mA Io = 5 mA Io = 4 mA Io = 0 mA 45 2.5 3 Vin (V) 3.5 4 Typical Iin vs. Io @25 Deg. C. 16 14 12 Iin (mA) 10 8 6 4 2 0 0 1 2 3 Io (mA) 4 Vin = 3.60V Vin = 3.30V Vin = 2.50V Vin = 2.25V Typical Eff. vs. Io @25 Deg. C. 60 Efficiency (%) 55 50 Vin = 2.25V Vin = 2.50V Vin = 3.30V Vin = 3.60V 45 6 4 5 4.5 5 Io (mA) 5.5 6 3 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 5mA CAPLESS TM CHARGE PUMP SC1460 PRELIMINARY - July 6, 1999 Typical Vo vs. Vin @25 Deg. C. 5 4.5 4 Vo (V) 3.5 3 2.5 2 2 2.5 3 Vin (V) 3.5 4 Io = 0 mA Io = 4 mA Io = 5 mA Io = 6 mA 4 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 5mA CAPLESS TM CHARGE PUMP SC1460 PRELIMINARY - July 6, 1999 Typical Eff. vs. Ta @ Io = 4 mA 70.0E-3 Typical Vo ripple vs. Cout @ Vin = 2.50V 57 60.0E-3 Iout = 4mA 56 50.0E-3 Efficiency (%) Vo ripple (V) Vin = 2.25 V Vin = 2.50 V Vin = 3.30 V Vin = 3.60 V 0 10 20 30 40 50 60 70 80 40.0E-3 55 30.0E-3 54 20.0E-3 10.0E-3 53 000.0E+0 22.0E-9 47.0E-9 56.0E-9 68.0E-9 82.0E-9 180.0E-9 220.0E-9 Ta (Deg. C.) Cout (F) Typical Vo vs. Ta @ Vin = 2.50V 3.5 3.4 3.3 3.2 3.1 Vo ripple Vo (V) 3 2.9 2.8 2.7 2.6 2.5 0 10 20 30 40 50 60 70 Io = 0mA Io = 4mA Io = 5mA Io = 6mA Ta (Deg. C.) Typical Iin vs. Ta @ Io = 0 mA 0.19 0.17 0.15 Iin (mA) 0.13 0.11 0.09 0.07 Vin = 2.25 V Vin = 2.50 V Vin = 3.30 V Vin = 3.60 V 0 10 20 30 40 50 60 70 0.05 Ta (Deg. C.) 5 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 5mA CAPLESS TM CHARGE PUMP SC1460 PRELIMINARY - July 6, 1999 OUTLINE DRAWING SOT-23-3L 6 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320