TC7662B TELCOM | Alldatasheet

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Technical content

4-83TELCOM SEMICONDUCTOR, INC. TC7662B CHARGE PUMP DC-TO-DC VOLTAGE CONVERTER

FEATURES

n Wide Operating Voltage Range: 1.5V to 15V n Boost Pin (Pin 1) for Higher Switching Frequency n High Power Efficiency is 96% n Easy to Use – Requires Only 2 External Non-Critical Passive Components n Improved Direct Replacement for Industry Stan- dard ICL7660 and Other Second Source Devices

APPLICATIONS

n Simple Conversion of +5V to ±5V Supplies n Voltage Multiplication VOUT = ±nV IN n Negative Supplies for Data Acquisition Systems and Instrumentation n RS232 Power Supplies n Supply Splitter, VOUT = ±VS/2 GENERAL DESCRIPTION The TC7662B is a pin-compatible upgrade to the Indus- try standard TC7660 charge pump voltage converter. It converts a +1.5V to +15V input to a corresponding – 1.5 to – 15V output using only two low-cost capacitors, eliminating inductors and their associated cost, size and EMI. The on-board oscillator operates at a nominal fre- quency of 10kHz. Frequency is increased to 35kHz when pin 1 is connected to V+, allowing the use of smaller external capacitors. Operation below 10kHz (for lower supply current applications) is also possible by connecting an external capacitor from OSC to ground (with pin 1 open). The TC7662B is available in both 8-pin DIP and 8-pin small outline (SO) packages in commercial and extended temperature ranges. FUNCTIONAL BLOCK DIAGRAM TC7662B GND INTERNAL VOLTAGE REGULATOR RC OSCILLATOR VOLTAGE– LEVEL TRANSLATOR ÷ 2 V + CAP + OSC LV LOGIC NETWORK VOUT CAP –4 1BOOST TC7662BCPA TC7662BEPA BOOST CAP + GND CAP – VOUT LOW VOLTAGE (LV) OSC +V 1 TC7662BCOA TC7662BEOA BOOST CAP + GND CAP – VOUT LOW VOLTAGE (LV) OSC PIN CONFIGURATION (DIP and SOIC)

ORDERING INFORMATION

Part No. Package Range TC7662BCOA 8-Pin SOIC 0 °C to +70°C TC7662BCPA 8-Pin Plastic DIP 0 °C to +70°C TC7662BEOA 8-Pin SOIC – 40 °C to +85°C TC7662BEPA 8-Pin Plastic DIP – 40 °C to +85°C TC7660EV Evaluation Kit for Charge Pump Family TC7662B-8 9/11/96 EVALUATION KIT AVAILABLE

4-84 TELCOM SEMICONDUCTOR, INC. ELECTRICAL CHARACTERISTICS: V+ = 5V, TA = +25°C, OSC = Free running, Test Circuit Figure 2, Unless Otherwise Specified. Symbol Parameter Test Conditions Min Typ Max Unit I+ Supply Current (Note 3) R L = ∞ , +25°C — 80 160 µA (Boost pin OPEN OR GND) 0 °C ≤ TA ≤ +70°C — — 180 µA I+ Supply Current 0 °C ≤ TA ≤ +70°C — — 300 µA (Boost pin = V+) – 40 °C ≤ TA ≤ +85°C 350 – 55°C ≤ TA ≤ +125°C 400 V+H Supply Voltage Range, High R L = 10 kΩ , LV Open, TMIN ≤ TA ≤ TMAX 3.0 — 15 V (Note 4) V+L Supply Voltage Range, Low R L = 10 kΩ , LV to GND, TMIN ≤ TA ≤ TMAX 1.5 — 3.5 V R OUT Output Source Resistance I OUT = 20 mA, 0°C ≤ TA ≤ +70°C — 65 100 Ω IOUT = 20 mA, – 40°C ≤ TA ≤ +85°C — — 120 Ω IOUT = 20 mA, - 55°C ≤ TA ≤ +125°C — — 150 Ω IOUT = 3 mA, V+ = 2V, LV to GND , — — 250 Ω 0°C ≤ TA ≤ +70°C IOUT = 3 mA, V+ = 2V, LV to GND , — — 300 Ω IOUT = 3 mA, V+ = 2V, LV to GND , — — 400 Ω fOSC Oscillator Frequency C OSC = 0, Pin 1 Open or GND 5 10 — kHz Pin 1 = V+ 35 PEff Power Efficiency R L = 5 kΩ 96 96 — % TMIN ≤ TA ≤ TMAX 95 97 VOUT Eff Voltage Conversion Efficiency R L = ∞ 99 99.9 — % ZOSC Oscillator Impedance V + = 2V — 1 — M Ω V+ = 5V — 100 — k Ω NOTES: 1. Connecting any terminal to voltages greater than V+ or less than GND may cause destructive latch-up. It is recommended that no inputs from sources operating from external supplies be applied prior to “power up” of the TC7662B. 2. Derate linearly above 50°C by 5.5 mW/°C. 3. In the test circuit, there is no external capacitor applied to pin 7. However, when the device is plugged into a test socket, there is usually a very small but finite stray capacitance present, of the order of 5pF. 4. The TC7662B can operate without an external diode over the full temperature and voltage range. This device will function in existing designs which incorporate an external diode with no degradation in overall circuit performance. ABSOLUTE MAXIMUM RATINGS* LV, Boost and OSC Inputs Voltage (Note 1) Current Into LV (Note 1) Output Short Duration Power Dissipation (TA ≤ 70°C) (Note 2) Operating Temperature Range *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 operation sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. TC7662B CHARGE PUMP DC-TO-DC VOLTAGE CONVERTER

4-90 TELCOM SEMICONDUCTOR, INC. TC7662B CHARGE PUMP DC-TO-DC VOLTAGE CONVERTER TYPICAL CHARACTERISTICS Supply Current vs. Temperature (with Boost Pin = VIN) 1000 200 400 600 800 -40 -20 0 20 40 100 60 80 IDD (µA) TEMPERATURE ( °C) VIN = 12V Without Load 10K Load Voltage Conversion 101.0 100.5 100.0 99.5 99.0 98.5 98.011 2 111098756423 VOLTAGE CONVERSION EFFICIENCY (%) INPUT VOLTAGE V IN (V) Output Voltage vs. Output Current -10 -12 OUTPUT VOLTAGE V OUT (V) OUTPUT CURRENT (mA) VIN = 5V IOUT = 20mA TA = 25°C Supply Current vs. Temperature 200 150 125 175 100 SUPPLY CURRENT I DD (µA) TEMPERATURE ( °C) 0 100 9080706040 503010 20 Output Source Resistance vs. Supply Voltage 100 OUTPUT SOURCE RESISTANCE ( Ω ) SUPPLY VOLTAGE (V) Output Source Resistance vs. Temperature 100 -40 -20 0 20 40 100 60 80 OUTPUT SOURCE RESISTANCE ( Ω ) TEMPERATURE ( °C) VIN = 2.5V VIN = 5.5V -40 -20 0 20 40 100 60 80 VIN = 12.5V VIN = 5.5V TA = 25°C

4-91TELCOM SEMICONDUCTOR, INC. TC7662B CHARGE PUMP DC-TO-DC VOLTAGE CONVERTER TYPICAL CHARACTERISTICS (Cont.) Unloaded Osc Freq vs. Temperature -40 -20 0 20 40 100 60 80 OSCILLATOR FREQUENCY (kHz) TEMPERATURE ( °C) VIN = 12V VIN = 5V Unloaded Osc Freq vs. Temperature with Boost Pin = VIN60 -40 -20 0 20 40 100 60 80 OSCILLATOR FREQUENCY (kHz) TEMPERATURE ( °C) VIN = 12V VIN = 5V