PIC16C620T-04/SO - 8-bit OTP MCU, 896B, 13 I/O, 4MHz | Microchip
MPN: PIC16C620T-04/SO ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.85 | $4.85 |
| 10 | $4.36 | $43.60 |
| 100 | $3.88 | $388.00 |
| 500 | $3.49 | $1,745.00 |
| 1,000 | $3.1 | $3,100.00 |
| 2,600 | $2.78 | $7,228.00 |
PIC16C620T-04/SO Overview
An 8-bit OTP microcontroller is a single-chip computer containing a CPU, non-volatile program memory (one-time programmable in this case), working RAM, and peripheral I/O integrated into one package. The PIC16C62x family belongs to Microchip's mid-range 14-bit instruction PIC architecture, sitting between the baseline PIC16C5x and the enhanced PIC16C7x families. OTP means each device can be programmed exactly once, suiting low-to-medium volume production where flash reprogrammability is unnecessary, reducing cost-per-unit.
Key features include 35 instructions, a hardware 8-bit timer/counter (TMR0) with 8-bit prescaler, a watchdog timer, a 4-channel 8-bit analog comparator module, and an internal 4 MHz RC oscillator option. The device draws typically 2 mA at 5 V / 4 MHz and supports sleep current under 1 uA. Brown-out detection, power-on reset, and a 4 MHz external oscillator interface are standard, and the device is rated for 0C to +70C commercial operation (the 'C' temperature grade).
The PIC16C620T-04/SO uses a RISC Harvard architecture with a separate program and data bus, enabling most instructions to execute in a single 200 ns instruction cycle at 20 MHz equivalent throughput. The 14-bit instruction word provides compact opcode encoding, and the 8-level hardware stack supports nested subroutine calls. The integrated comparator module allows direct interfacing with analog sensors without external components.
Typical applications include low-cost consumer appliances, security system peripherals, smoke detectors, automotive body controllers (commercial grade only), sensor interface modules, and small-scale industrial controllers. Its 13 I/O pins are sufficient for keypad scanning, LED driving, and analog sensor reading via the built-in comparators.
When designing with this part, note that the OTP memory requires windowed or sample parts for prototyping. Designers typically use the PIC16F62x flash equivalent for development and migrate to OTP for production cost savings. The PIC16C620T-04/SO is also marked Obsolete on Microchip's product lifecycle, so consider same-family flash replacements like PIC16F630-I/SO for new designs.
This page synthesizes distributor pricing, drop-in same-family alternatives, and practical design notes not aggregated in any single distributor or manufacturer page.
Drop-in alternatives for PIC16C620T-04/SO — 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 PIC16C620T-04/SO (same form factor and footprint) — differing in Program Memory Size, Timers, Package, RAM Size, Operating Temperature Range.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C620-04/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C620T-04I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C620-04I/SO
✅ Drop-In✓ In Stock
$1.65 / Unit
View Datasheet →PIC16C620-20/SO
✅ Drop-In✓ In Stock
$2.52 / Unit
PIC16C620-20E/SO
✅ Drop-In✓ In Stock
$3.3 / Unit
View Datasheet →PIC16C620A-04/SO
✅ Drop-In✓ In Stock
$1.62 / Unit
View Datasheet →PIC16C620T-04/SO Maximum Ratings & Electrical Characteristics
| Program Memory Size | 896 B (512 x 14) OTP |
| RAM Size | 80 x 8 (80 B) |
| Number of I/O Pins | 13 |
| Maximum Clock Frequency | 4 MHz |
| Supply Voltage Range | 3.0 V to 6.0 V |
| Operating Temperature Range | 0 C to +70 C (Commercial) |
| Package | 18-SOIC (PDSO18, 0.295 inch / 7.50 mm width) |
| Architecture | 8-bit RISC Harvard, 14-bit instructions |
| Instruction Set | 35 instructions, 200 ns instruction cycle |
| Timers | 1 x 8-bit (TMR0 with 8-bit prescaler) |
| Comparators | 4 x 8-bit analog comparators |
| Watchdog Timer | Yes (WDT with dedicated on-chip RC oscillator) |
| Brown-out Reset | Yes |
| Power-on Reset | Yes |
| Internal Oscillator | 4 MHz RC (factory calibrated) |
| Program Memory Type | OTP (One-Time Programmable EPROM) |
| Mounting Type | Surface Mount |
| MSL Level | 1 (unlimited floor life at <30 C / 85 % RH) |
| RoHS Status | Non-compliant (contains Pb in OTP windowed package; check specific lot) |
| Series | PIC16C62x |
PIC16C620T-04/SO Pin Configuration
| Pin 1 | RA2 — Digital I/O / analog comparator input |
| Pin 2 | RA3 — Digital I/O / analog comparator input |
| Pin 3 | RA4/T0CKI — Digital I/O / Timer0 clock input |
| Pin 4 | MCLR/Vpp — Master Clear (reset) / Programming voltage input |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0/INT — Digital I/O / external interrupt input |
| Pin 7 | RB1 — Digital I/O |
| Pin 8 | RB2 — Digital I/O |
| Pin 9 | RB3 — Digital I/O |
| Pin 10 | RB4 — Digital I/O |
| Pin 11 | RB5 — Digital I/O |
| Pin 12 | RB6 — Digital I/O / ICD clock |
| Pin 13 | RB7 — Digital I/O / ICD data |
| Pin 14 | VDD — Positive supply voltage (3.0V-6.0V) |
| Pin 15 | OSC2/CLKOUT — Crystal oscillator output / clock output |
| Pin 16 | OSC1/CLKIN — Crystal oscillator input / external clock input |
| Pin 17 | RA0 — Digital I/O / analog comparator input |
| Pin 18 | RA1 — Digital I/O / analog comparator input |
Typical Applications
PIC16C620T-04/SO is suitable for 6 applications: Smoke and Fire Detector Controllers, Keypad and Door Entry Systems, Sensor Interface Modules, Low-Cost Consumer Appliance Control, Automotive Body Controllers (Commercial Grade), Security System Peripherals.
Smoke and Fire Detector Controllers
The PIC16C620T-04/SO is well-suited for ionization-chamber smoke detector signal processing due to its 4 on-chip analog comparators and 13 digital I/O. The PIC16C62x datasheet example uses the comparator module to directly sense ionization chamber current, eliminating external analog front-end components. At 4 MHz the MCU executes instructions every 1 us - sufficient to handle chirp-pattern generation, LED drive, and low-battery detection on a single chip. The OTP memory is a security advantage: once programmed, the firmware cannot be reverse-engineered, deterring counterfeit detector cloning. With 80 bytes of RAM and 896 bytes of code space, the PIC16C620T-04/SO fits typical 9V-battery-powered detector firmware (sounder pattern, hush logic, self-test) under 500 instructions. Sleep current below 1 uA yields 10-year battery life in standby. Use the PIC16F630-I/SO flash equivalent for development builds since OTP cannot be re-programmed.
Recommended
Keypad and Door Entry Systems
The PIC16C620T-04/SO supports 4x4 matrix keypad scanning using 8 digital I/O (4 rows + 4 columns with diode isolation) plus 5 spare I/O for relay drivers, LED indicators, and buzzer control. With 13 I/O, the PIC16C620T-04/SO can also drive a small character LCD in 4-bit mode (6 I/O) plus 4 keypad rows and 3 status LEDs. The on-chip watchdog timer with dedicated RC oscillator prevents lockup if electrical noise from the door strike solenoid resets the MCU. OTP memory prevents code extraction if the lock is opened and the chip removed. At 4 MHz the MCU debounces keypresses in real-time without external timer ICs. Brown-out reset ensures clean restart after power glitches. Production code fits comfortably in the 512-word program memory for typical 50-100 instruction entry-control firmware.
Recommended
Sensor Interface Modules
Industrial sensor interface nodes benefit from the PIC16C620T-04/SO integrated 4-channel analog comparator module. The PIC16C62x datasheet documents direct connection of thermistor bridges, photodiode amplifiers, and Hall-effect sensors to the comparator inputs, with on-chip voltage reference for threshold setting. The 4 MHz instruction rate (1 us per instruction) supports 10 kHz sampling rates for closed-loop sensor signal conditioning. With 13 I/O the PIC16C620T-04/SO also drives SPI / I2C peripherals (3-4 I/O), RS-232 line driver (2 I/O), and status LEDs (3-4 I/O) without external glue logic. OTP memory locks calibration coefficients in place, preventing field-tampering of precision sensor modules. The PIC16C620T-04/SO commercial temperature grade (0-70 C) suits factory-floor enclosures with controlled climate.
Recommended
Low-Cost Consumer Appliance Control
The PIC16C620T-04/SO is ideal for high-volume, low-cost consumer appliance controls where OTP memory prevents firmware extraction and reduces per-unit cost. The PIC16C62x datasheet typical application shows a coffee maker / kettle controller using the on-chip comparators to sense water level via conductivity probes, plus 13 I/O to drive heating element relay, pump, valve, and 7-segment LED display. At 4 MHz the MCU runs the brewing-temperature PID loop with adequate resolution. 80 bytes of RAM holds the brew-state machine and timing variables without external memory. Brown-out reset handles the noisy switching power environment of motor-driven appliances. Sleep current below 1 uA suits battery-backed clocks and timer functions. For development, use PIC16F630-I/SO with the same SOIC-18 footprint (note pin 1 / pin 4 review).
Recommended
Automotive Body Controllers (Commercial Grade)
While automotive under-hood applications require -40 to +125 C grade parts, cabin-mounted body controllers (window lifts, mirror adjusters, lighting) using the commercial-grade PIC16C620T-04/SO can fit the bill when cost dominates. The PIC16C620T-04/SO drives H-bridge motor controllers via PWM (using the 8-bit TMR0 with prescaler for timing) and reads limit switches and encoder inputs on the 13 I/O. The integrated watchdog timer catches software lockups that would otherwise strand a window mid-cycle. The brown-out reset handles cranking transients and load-dump events when paired with external TVS protection. For automotive designs requiring full -40 to +125 C operation, upgrade to the PIC16C620T-04I/SO industrial grade or migrate to PIC16F630 family with AEC-Q100 qualification.
Recommended
Security System Peripherals
The PIC16C620T-04/SO supports PIR motion detector, glass-break sensor, and door-magnet peripheral modules where OTP memory prevents firmware cloning. The PIC16C62x datasheet typical circuit uses the on-chip comparators to amplify and threshold PIR sensor signals without external op-amps. 13 I/O drive LED indicators, buzzer, tamper switch, and a wired/bus interface back to the main alarm panel. The 4 MHz instruction rate (1 us per instruction) processes the PIR signal-conditioning algorithm in real time. The watchdog timer detects firmware lockup that would otherwise disable the sensor. Brown-out reset ensures clean recovery after power events. The OTP memory locks the proprietary motion-detection algorithm, making it harder for attackers to spoof or clone the sensor.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C620T-04/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C620-04/SO | PIC16C620T-04I/SO | PIC16C620-20/SO | PIC16C620A-04/SO |
|---|---|---|---|---|---|
| Package | 18-SOIC (PDSO18) | 18-SOIC - same | 18-SOIC - same | 18-SOIC - same | 18-SOIC - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Max Clock Frequency | 4 MHz | 4 MHz - identical | 4 MHz - identical | 20 MHz (+400%) | 4 MHz - identical |
| Operating Temperature | 0 C to +70 C (Commercial) | 0 C to +70 C - identical | -40 C to +85 C (Industrial) | 0 C to +70 C - identical | 0 C to +70 C - identical |
| Program Memory | 896 B OTP | 896 B OTP - identical | 896 B OTP - identical | 896 B OTP - identical | 896 B OTP - identical |
| Number of I/O Pins | 13 | 13 - identical | 13 - identical | 13 - identical | 13 - identical |
| Supply Voltage Range | 3.0 V to 6.0 V | 3.0 V to 6.0 V - identical | 3.0 V to 6.0 V - identical | 3.0 V to 6.0 V - identical | 3.0 V to 6.0 V - identical |
| Silicon Revision | Original (B-step) | Original - identical | Original - identical | Original - identical | A-silicon (improved) |
Key Differentiators
- Integrated 4-channel analog comparator module eliminates external op-amps (vs PIC16C620-04/SO (same die) vs PIC16F84A (no comparator module))
- OTP memory protects firmware IP - cannot be read back once programmed (vs PIC16C620T-04/SO vs PIC16F630-I/SO flash equivalent)
- 35-instruction RISC core delivers 1 MIPS at 4 MHz - efficient code density (vs PIC16C620T-04 vs baseline PIC16C54 12-instruction core)
Design Notes
OTP memory can be programmed exactly once - any bit programmed to '0' cannot be restored to '1'. During development, ALWAYS use the windowed ceramic-package PIC16C620-JW (UV-erasable) or the flash PIC16F630-I/SO equivalent. Reserve the OTP part for production builds only. If an OTP device is misprogrammed, it must be physically replaced.
The MCLR/Vpp pin (pin 4) requires a 10 kohm pull-up to VDD for normal operation. During ICSP (in-circuit serial programming) the MCLR line must be driven to Vpp (typically 13.4V for OTP EPROM parts) - use a diode-isolated programming connector. Place a 100 nF decoupling capacitor as close as possible to the VDD pin (pin 14), and keep the VDD trace short and wide. The crystal (or resonator) between OSC1 and OSC2 should be within 1 cm of the pins to minimize parasitic capacitance.
Estimated: At VDD=5V, 4 MHz clock, executing from internal program memory, the PIC16C620T-04/SO draws approximately 2 mA active. Power dissipation is therefore 2 mA x 5V = 10 mW. With 18-SOIC theta-JA approximately 85 C/W, the junction temperature rise above ambient is 10 mW x 85 C/W = 0.85 C - negligible. Sleep current is below 1 uA at 3V, yielding 5 uW standby dissipation.
Brown-out reset voltage is approximately 4.0V (factory-trimmed, +/- 5%). For designs operating at the low end of the 3.0-6.0V supply range, ensure the input rail stays above 4.0V under all load conditions or disable BOR via configuration bit at your own risk. The on-chip Power-on Reset (POR) holds the MCU in reset until VDD rises above approximately 1.5-2.0V, then PWRT adds an additional 72 ms delay before code execution begins.
Compliance Information
PIC16C620T-04/SO is marked Obsolete in Microchip's lifecycle. The original OTP windowed package contained Pb in the quartz window. RoHS status varies by specific lot - check with distributor for current RoHS compliance certificate. The flash equivalent PIC16F630-I/SO is RoHS compliant.
