TC7662A TELCOM | Alldatasheet

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Technical content

4-77TELCOM SEMICONDUCTOR, INC. TC7662A COMPARATOR WITH HYSTERESIS C F/F Q Q VREF LEVEL SHIFT LEVEL SHIFT LEVEL SHIFT LEVEL SHIFT VDD P SW1 CAP C P EXT N SW4 N SW2 N SW3 CAP C R EXT R L V I C OSC GND OUT OUT TC7662A GENERAL DESCRIPTION The TC7662A is a pin-compatible upgrade to the In- dustry standard TC7660 charge pump voltage converter. It converts a +3V to +18V input to a corresponding – 3V to -18V output using only two low-cost capacitors, eliminating inductors and their associated cost, size and EMI. In addi- tion 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 be- low 10kHz (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 DIP packages in com- mercial and extended temperature ranges.

FEATURES

n Pin Compatible with ICL7662/SI7661/TC7660/ LTC1044 n No External Diodes Required n No Low-Voltage Terminal Required n CMOS Construction FUNCTIONAL BLOCK DIAGRAM CHARGE PUMP DC-TO-DC CONVERTER TC7662A VDD OSC VOUT NC C + GND C – NC NC = NO INTERNAL CONNECTION PIN CONFIGURATION EVALUATION KIT AVAILABLE

ORDERING INFORMATION

Part No. Package Range TC7662ACPA 8-Pin Plastic DIP 0 °C to +70°C TC7662AEPA 8-Pin Plastic DIP – 40 °C to +85°C TC7662AIJA 8-Pin CerDIP – 25 °C to +85°C TC7662AMJA 8-Pin CerDIP – 55 °C to +125°C TC7660EV Evaluation Kit for Charge Pump Family TC7662A-5 9/11/96

4-78 TELCOM SEMICONDUCTOR, INC. ABSOLUTE MAXIMUM RATINGS* Operating Temperature Range Power Dissipation (T A ≤ 70°C) Package Thermal Resistance CPA, EPA θ *Static-sensitive device. Unused devices must be stored in conductive material. Protect devices from static discharge and static fields. Stresses above those listed under Absolute Maximum Ratings may cause perma- nent 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 operational sections of the specifications is not implied. Exposure to Absolute Maximum Rating Conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS: VDD = 15V , TA = +25°C (See Test Circuit), unless otherwise specified. Symbol Parameter Test Conditions Min Typ Max Unit V DD Supply Voltage 3 — 18 V IS Supply Current R L = ∞ V DD = +15V — 510 700 µA V DD = +5V — 190 — R O Output Source I L = 20mA, VDD = +15V — 40 50 Ω Resistance I L = 40mA, VDD = +15V — 50 60 IL = 3mA, VDD = +5V — 100 125 C OSC Oscillator Frequency — 12 — kHz PEFF Power Efficiency V DD = +15V 93 97 — % R L = 2 kΩ VEFF Voltage Efficiency V DD = +15V 99 99.9 — % R L = ∞ Over Operating Temperature Range 96 — — CHARGE PUMP DC-TO-DC CONVERTER TC7662A

4-80 TELCOM SEMICONDUCTOR, INC. CHARGE PUMP DC-TO-DC CONVERTER TC7662A TYPICAL APPLICATIONS

3 TC7662A

10 µF V + 10 µF V = –VOUT VD1 VD2 V = 2V –2VOUT D 10 µF Combined Negative Converter and Positive Multiplier C P1 10 µF + CP2 10 µF TC7662A TC7662A V + VOUT 10 µF C R TC7662A 10 µF 10 µF C P C R V = 2V –2 VOUT D +VD2 VD1 V + C P 10 µF 100 µF C R + V =OUT V Split V In Half+ Lowering Output Resistance by Paralleling Devices Positive Voltage Multiplier TC7662A

4-81TELCOM SEMICONDUCTOR, INC. CHARGE PUMP DC-TO-DC CONVERTER TC7662A TYPICAL CHARACTERISTICS 700 600 500 400 300 200 100 –60 –40 –20 0 20 40 60 80 100 120 140 TEMPERATURE ( °C) SUPPLY CURRENT ( µA) V = 15V V = 5V+ Supply Current vs. Temperature 100 1 10 100 1000 10,000 CAPACITANCE (pF) FREQUENCY (Hz) Oscillator Frequency vs. CEXT 10k TA = +25°C –60 –40 –20 0 20 40 60 80 100 120 140 TEMPERATURE ( °C) FREQUENCY (kHz) Frequency vs. Temperature 160 140 120 100 –60 –40 –20 0 20 40 60 80 100 120 140 TEMPERATURE ( °C) OUTPUT RESISTANCE ( ) V = 15V, I = 20 mA Output Resistance vs. Temperature L V = 5V, I = 3 mA Ω 100 LOAD CURRENT (mA) POWER CONVERSION EFFICIENCY (%) Power Conversion Efficiency vs. I 16 32 48 64 80 82 4 4 05 6 7 20 LOAD 150 120 135 105 SUPPLY CURRENT (mA) EFFICIENCY SUPPLY CURRENT 110 TA = +25°C 165 100 INPUT VOLTAGE (V) OUTPUT RESISTANCE ( ) Output Resistance vs. Input Voltage 4 8 12 16 20 2 6 10 14 180 Ω 110 20 mA TA = +25°C