TC7662ACPA

TC7662A Charge Pump DC-to-DC Converter Package Type Features • Wide Operating Range - 3V to 18V • Increased Output Current (40mA) • Pin Compatible with ICL7662/SI7661/TC7660/ LTC1044 • No External Diodes Required • Low Output Impedance @ IL = 20mA - 40 Typ. • No Low-Voltage Terminal Required • CMOS Construction • Available in 8-Pin PDIP and 8-Pin CERDIP Packages Applications • • • • Laptop Computers Disk Drives Process Instrumentation P-based Controllers Device Selection Table Operating Temp. Range Part Number Package TC7662ACPA 8-Pin PDIP 0°C to +70°C TC7662AEPA 8-Pin PDIP -40°C to +85°C TC7662AIJA 8-Pin CERDIP -25°C to +85°C TC7662AMJA 8-Pin CERDIP -55°C to +125°C  2001-2012 Microchip Technology Inc. 8-Pin PDIP 8-Pin CERDIP NC 1 8 VDD C+ 2 GND 3 6 NC C– 4 5 VOUT TC7662A 7 OSC General Description The TC7662A is a pin-compatible upgrade to the industry standard TC7660 charge pump voltage converter. It converts a +3V to +18V input to a corresponding -3V to -18V output using only two lowcost capacitors, eliminating inductors and their associated cost, size and EMI. In addition to a wider power supply input range (3V to 18V versus 1.5V to 10V for the TC7660), the TC7662A can source output currents as high as 40mA. The on-board oscillator operates at a nominal frequency of 12kHz. Operation below 12kHz (for lower supply current applications) is also possible by connecting an external capacitor from OSC to ground. The TC7662A directly is recommended for designs requiring greater output current and/or lower input/ output voltage drop. It is available in 8-pin PDIP and CERDIP packages in commercial and extended temperature ranges. DS21468B-page 1 TC7662A Functional Block Diagram 8 VDD I OSC TC7662A 7 Q + – F/F C Q Comparator with Hysteresis Level Shift P SW1 2 Level Shift N SW4 CAP + + CP EXT GND 3 VREF + Level Shift OUT 4 Level Shift CR EXT N SW2 CAP – RL N SW3 5 VOUT DS21468B-page 2  2001-2012 Microchip Technology Inc. TC7662A 1.0 ELECTRICAL CHARACTERISTICS Stresses above 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 above those indicated in the operation sections of the specifications is not implied. Exposure to Absolute Maximum Rating conditions for extended periods may affect device reliability. Absolute Maximum Ratings* Supply Voltage VDD to GND................................. +18V Input Voltage (Any Pin) .........(VDD + 0.3) to (VSS – 0.3) Current into Any Pin ............................................ 10mA Output Short Circuit ........... Continuous (at 5.5V Input) ESD Protection ................................................ ±2000V Package Power Dissipation (TA  70°C) 8-Pin CERDIP .......................................... 800mW 8-Pin PDIP ............................................... 730mW Package Thermal Resistance CPA, EPA JA ......................................... 140°C/W IJA, MJA JA ............................................ 90°C/W Operating Temperature Range C Suffix............................................ 0°C to +70°C I Suffix .......................................... -25°C to +85°C E Suffix......................................... -40°C to +85°C M Suffix ...................................... -55°C to +125°C Storage Temperature Range.............. -65°C to +150°C TC7662A ELECTRICAL SPECIFICATIONS Electrical Characteristics: VDD = 15V, TA = +25°C, Test circuit (Figure 3-1) unless otherwise noted. Symbol Parameter Min Typ Max Units Test Conditions VDD Supply Voltage 3 — 18 V IS Supply Current — — — — — — — — 510 560 650 190 210 210 — 700 — — — — — A RL =  VDD = +15V 0C  TA  +70C -55°C  TA  +125°C VDD = +5V 0C  TA  +70C -55°C  TA  +125°C RO Output Source Resistance — — — 40 50 100 50 60 125  IL = 20mA, VDD = +15V IL = 40mA, VDD = +15V IL = 3mA, VDD = +5V FOSC Oscillator Frequency — 12 — kHz PEFF Power Efficiency 93 — 97 — — — % VDD = +15V RL = 2k VEFF Voltage Efficiency 99 — 96 99.9 — — — — — % VDD = +15V RL =  Over operating temperature range.  2001-2012 Microchip Technology Inc. DS21468B-page 3 TC7662A 2.0 PIN DESCRIPTIONS The descriptions of the pins are listed in Table 2-1. TABLE 2-1: PIN FUNCTION TABLE Pin No. (8-Pin PDIP, CERDIP) Symbol 1 NC 2 C+ 3 GND 4 C- 5 VOUT Output voltage. 6 NC No connection. 7 OSC Oscillator control input. Bypass with an external capacitor to slow the oscillator. 8 VDD Power supply positive voltage input. DS21468B-page 4 Description No connection. Charge pump capacitor positive terminal. Ground terminal. Charge pump capacitor negative terminal.  2001-2012 Microchip Technology Inc. TC7662A 3.0 DETAILED DESCRIPTION 3.1 The TC7662A is a capacitive charge pump (sometimes called a switched-capacitor circuit), where four MOSFET switches control the charge and discharge of a capacitor. The functional block diagram shows how the switching action works. SW1 and SW2 are turned on simultaneously, charging CP to the supply voltage, VDD. This assumes that the ON resistance of the MOSFETs in series with the capacitor produce a charging time (3 time constants) less than the ON time provided by the oscillator frequency, as shown: 3 (RDS(ON) CP)