TC7660SEOA - 20mA Super Charge Pump DC-DC Converter | Microchip
MPN: TC7660SEOA ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.35 | $1.35 |
| 10 | $1.21 | $12.10 |
| 100 | $1.08 | $108.00 |
| 500 | $0.97 | $485.00 |
| 1,000 | $0.86 | $860.00 |
| 3,000 | $0.76 | $2,280.00 |
TC7660SEOA Overview
A charge pump DC-DC converter is a type of switching voltage regulator that uses capacitors rather than magnetic inductors to store and transfer energy. Charge pumps sit within the broader hierarchy of DC-DC converters -> switching regulators -> power management ICs -> semiconductors. They are favored in low-power, noise-sensitive designs because they generate no magnetic EMI and require only two capacitors, making them ideal for compact analog front ends where a small negative supply rail is needed without the bulk of an inverting buck-boost converter.
Key features of the TC7660SEOA include pin-compatibility with the industry-standard 7660 footprint, a wide 1.5 V to 12 V input range that can be doubled to 12 V to 24 V using the internal oscillator doubling mode, and a typical quiescent current in the microamp range. The on-board CMOS oscillator nominally operates at 10 kHz, with an optional external clock input for synchronization. The device includes a BOOST pin reference, low output impedance (~55 ohm typical), and operates across the -40C to +85C commercial temperature range, suiting RS-232 drivers, op-amp negative rails, and portable instrumentation.
Internally, the TC7660SEOA uses CMOS transistors configured as an H-bridge switched-capacitor network clocked by the on-chip oscillator. During one clock phase, the flying capacitor is charged to +Vin; during the alternate phase, it is flipped and discharged into the reservoir capacitor at -Vin. The architecture avoids the switching spikes common to inductive converters, and its symmetrical pinout supports cascading two devices for voltage doubling.
Typical applications include generating the -5 V to -12 V rail for RS-232 transceivers, negative bias supplies for op-amps and LCD contrast, low-current analog signal conditioning, and portable data-acquisition systems. When designing with this device, keep the flying capacitor ESR low (typically 10 uF) and place reservoir capacitors close to pins 5 and 8 to minimize ripple and load-transient overshoot.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes that go beyond the manufacturer datasheet to help engineers select and source the TC7660SEOA with confidence.
Drop-in alternatives for TC7660SEOA — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with TC7660SEOA (same form factor and footprint) — differing in Internal Oscillator Frequency, Mounting Type, Operating Temperature Range, Output Current, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
TC7660SEPA
✅ Drop-In📋 Reference alternative (not in catalog)
TC7660SCPA
✅ Drop-In📋 Reference alternative (not in catalog)
TC7660SCOA
✅ Drop-In✓ In Stock
$0.81 / Unit
View Datasheet →ICL7660SIBAZ
✅ Drop-In📋 Reference alternative (not in catalog)
ICL7660AIBAZA
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1044ESA
✅ Drop-In📋 Reference alternative (not in catalog)
TC7660SEOA Maximum Ratings & Electrical Characteristics
| Topology | Charge Pump (Switched Capacitor), Inverting / Doubling |
| Input Voltage Range | +1.5 V to +12 V |
| Output Voltage | -Vin or 2Vin (selectable) |
| Output Current | 20 mA (typical) |
| Output Resistance | 55 ohm (typical) |
| Internal Oscillator Frequency | 10 kHz (nominal) |
| External Clock Input | Yes (OSC pin) |
| Operating Temperature Range | -40C to +85C |
| Package | 8-SOIC (0.154", 3.90 mm width) |
| Pin Count | 8 |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Number of External Capacitors Required | 2 (flying + reservoir) |
| Pin-Compatible With | Industry standard TC7660 / ICL7660 |
TC7660SEOA Pin Configuration
| Pin 1 | LV — Low-voltage pin; connect to GND for input above 3.5 V (doubler mode), or leave open for standard inverting mode |
| Pin 2 | CAP+ — Flying capacitor positive terminal |
| Pin 3 | GND — Ground reference |
| Pin 4 | CAP- — Flying capacitor negative terminal |
| Pin 5 | VOUT — Regulated negative output voltage (-Vin or 2Vin) |
| Pin 6 | VDD — Positive supply input (+1.5 V to +12 V) |
| Pin 7 | OSC — Oscillator control pin; tie to VDD for internal 10 kHz oscillator, or drive with external clock |
| Pin 8 | BOOST — Boost pin for cascading two TC7660S devices for higher output |
Typical Applications
TC7660SEOA is suitable for 6 applications: RS-232 Transceiver Negative Power Supply, Op-Amp Negative Rail Generator, LCD Display Contrast Bias Supply, Portable Instrumentation Negative Rail, Sensor Signal Conditioning Negative Bias, Vintage Audio and Synthesizer Circuit Power.
RS-232 Transceiver Negative Power Supply
The TC7660SEOA generates -5 V to -12 V from a +5 V or +12 V logic rail to power RS-232 driver charge-pump capacitors and discrete RS-232 transceivers requiring a negative supply. Its 20 mA output is sufficient for most legacy MAX232-style interfaces and the on-board 10 kHz oscillator matches RS-232 charge-pump frequency requirements. Unlike switching buck regulators, the TC7660SEOA adds no magnetic EMI to the analog signal chain. Place a 10 uF flying capacitor between pins 2 and 4, and a 10 uF reservoir capacitor on pin 5 for typical 5 V-to-negative-5 V operation.
Recommended
Op-Amp Negative Rail Generator
Many dual-supply op-amps and instrumentation amplifiers require a small negative rail (typically -5 V to -12 V) for AC-coupled signal paths or true bipolar operation. The TC7660SEOA delivers up to 20 mA with 55 ohm output impedance, enough for a single op-amp channel or low-power ADC reference. The pin-compatible 8-SOIC footprint drops directly onto legacy ICL7660 layouts. Source: Microchip datasheet DS21465. Use the doubler mode (pin 1 to GND) when converting +12 V to -24 V for high-voltage op-amps.
Recommended
LCD Display Contrast Bias Supply
Character LCD modules and some TFT panels need a negative bias voltage (typically -5 V to -12 V) for contrast adjustment or gate driver bias. The TC7660SEOA generates this bias from the +5 V logic rail using only two capacitors, eliminating the need for an isolated inverting DC-DC converter. The 20 mA output current supports most 16x2 to 40x4 character LCD contrast requirements. Place the reservoir capacitor close to pin 5 to minimize contrast flicker on high-impedance LCD inputs.
Recommended
Portable Instrumentation Negative Rail
Battery-powered data-acquisition systems, handheld multimeters, and field instruments often need a small negative reference or op-amp supply from a single lithium cell. The TC7660SEOA accepts +1.5 V to +12 V input, making it compatible with single-cell Li-ion (3.7 V nominal) and two-cell alkaline (3 V) sources. With typical quiescent current in the microamp range, it extends battery life in low-duty-cycle measurements. The pin-compatible 8-SOIC footprint simplifies PCB layout in compact handheld enclosures.
Recommended
Sensor Signal Conditioning Negative Bias
Some pressure sensors, strain gauges, and piezoelectric sensors need a small negative bias to operate in their linear range. The TC7660SEOA provides a clean -5 V to -12 V bias from a +5 V or +12 V sensor excitation rail. Its low output impedance (~55 ohm) ensures stable bias under varying sensor loads, while the absence of switching inductor EMI prevents interference with sensitive analog measurement chains.
Recommended
Vintage Audio and Synthesizer Circuit Power
Vintage audio circuits, Eurorack synthesizer modules, and guitar effect pedals often use legacy +/-15 V op-amp supplies but need a small negative rail when running from a single +9 V or +12 V battery. The TC7660SEOA generates the negative rail from the positive battery voltage, enabling single-supply operation of classic bipolar audio designs. The pin-compatible 8-SOIC footprint drops directly into legacy ICL7660 designs from the 1980s.
Recommended
Recommended Products Summary
Engineering reference data for TC7660SEOA — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | TC7660SEPA | TC7660SCPA | TC7660SCOA | ICL7660SIBAZ | ICL7660AIBAZA | MAX1044ESA |
|---|---|---|---|---|---|---|---|
| Package | 8-SOIC (0.154", 3.90 mm) | 8-PDIP | 8-PDIP | 8-CERDIP | 8-SOIC (pin-compatible) | 8-SOIC (pin-compatible) | 8-SOIC (pin-compatible) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Renesas Electronics | Renesas Electronics | Maxim Integrated |
| Input Voltage Range | +1.5 V to +12 V | +1.5 V to +12 V | +1.5 V to +12 V | +1.5 V to +12 V | +1.5 V to +12 V | +1.5 V to +12 V | +1.5 V to +12 V |
| Output Current | 20 mA | 20 mA | 20 mA | 20 mA | 20 mA | 20 mA | 20 mA |
| Output Voltage | -Vin or 2Vin | -Vin or 2Vin | -Vin or 2Vin | -Vin or 2Vin | -Vin or 2Vin | -Vin or 2Vin | -Vin or 2Vin |
| Oscillator Frequency | 10 kHz typical | 10 kHz typical | 10 kHz typical | 10 kHz typical | 10 kHz typical | 10 kHz typical | 10 kHz typical |
| Pin 1 Function | LV (functional) | LV (functional) | LV (functional) | LV (functional) | LV (functional) | NC (no connect) | LV (functional) |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
Key Differentiators
- SMT 8-SOIC package option with same die as 8-PDIP TC7660SEPA (vs TC7660SEPA)
- Pin 1 LV pin functional vs NC on some ICL7660 AI variants (vs ICL7660AIBAZA)
- True Microchip-manufactured Super Charge Pump version (vs MAX1044ESA)
Design Notes
Place the flying capacitor (typically 10 uF low-ESR ceramic) between pins 2 (CAP+) and 4 (CAP-) as close as possible to the IC, keeping traces short and matched. Place the reservoir capacitor (10 uF) on pin 5 (VOUT) close to the device. Source: Microchip TC7660 datasheet DS21465. Long traces introduce parasitic inductance that degrades output regulation and increases ripple.
Pin 1 (LV) must be left open or tied to VDD for standard inverting mode below 3.5 V input; tie to GND for doubler mode above 3.5 V input. Connecting pin 1 incorrectly prevents oscillation. Source: Microchip datasheet DS21465. Also, do not exceed the 12 V absolute maximum on VDD (pin 6) - transients above 13 V will damage the CMOS transistors.
At +5 V input and 20 mA load, the TC7660SEOA dissipates approximately 100 mW into the 8-SOIC package, well within the 470 mW absolute maximum at 25C. The 8-SOIC has theta_JA around 170 C/W. Estimated: at 70C ambient, junction temperature rises about 17C above ambient at 20 mA load. No heatsink required for typical RS-232 and op-amp supply applications.
The internal 10 kHz oscillator operates in the audible range, which can couple into sensitive audio circuits. For audio applications, drive pin 7 (OSC) with an external clock above 20 kHz to push switching noise above the audible band. Source: Microchip datasheet DS21465. Decouple pin 6 (VDD) with a 0.1 uF ceramic capacitor in parallel with the 10 uF bulk capacitor to suppress switching noise.
Compliance Information
RoHS and REACH compliant per Microchip product page. Not AEC-Q100 qualified - this is a commercial-grade part. For automotive applications, source AEC-Q100 qualified alternatives or implement additional qualification testing.
