Orderable parts
| Type number | Orderable part number | Ordering code (12NC) | Package | Buy from distributors |
|---|---|---|---|---|
| HEF4521BT | HEF4521BT,653 | 933406770653 | SOT109-1 | Order product |
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Click here for more informationHEF4521BT
24-stage frequency divider and oscillator
The HEF4521B consists of a chain of 24 toggle flip-flops with an overriding asynchronous master reset input (MR), and an input circuit that allows three modes of operation. The single inverting stage (A2 to Y2) functions as: a crystal oscillator, an input buffer for an external oscillator or in combination with A1 as an RC oscillator. The crystal oscillator operates in Low-power mode when pins VSS1 and VDD1 are supplied via external resistors.
Each flip-flop divides the frequency of the previous flip-flop by two, consequently the HEF4521B counts up to 224 = 16777216. The counting advances on the HIGH-to-LOW transition of the clock (A2). The outputs from each of the last seven stages (218 to 224) are available for additional flexibility.
It operates over a recommended VDD power supply range of 3 V to 15 V referenced to VSS (usually ground). Unused inputs must be connected to VDD, VSS, or another input.
Alternatives
Features and benefits
Wide supply voltage range from 3.0 V to 15.0 V
CMOS low power dissipation
High noise immunity
Low power crystal oscillator operation
Fully static operation
5 V, 10 V, and 15 V parametric ratings
Standardized symmetrical output characteristics
Complies with JEDEC standard JESD 13-B
- ESD protection:
HBM: ANSI/ESDA/JEDEC JS-001 class 2 exceeds 2000 V
CDM: ANSI/ESDA/JEDEC JS-002 class C3 exceeds 1000 V
Specified from -40 °C to +85 °C
Parametrics
| Type number | VCC (V) | Output drive capability (mA) | Logic switching levels | tpd (ns) | Power dissipation considerations | Tamb (°C) | Package name |
|---|---|---|---|---|---|---|---|
| HEF4521BT | 3.0 - 15 | ± 2.4 | CMOS | 220 | medium | -40~85 | SO16 |
PCB Symbol, Footprint and 3D Model
| Model Name | Description |
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Package
| Type number | Orderable part number, (Ordering code (12NC)) | Status | Marking | Package | Package information | Reflow-/Wave soldering | Packing |
|---|---|---|---|---|---|---|---|
| HEF4521BT | HEF4521BT,653 (933406770653) |
Active | HEF4521BT |
SO16 (SOT109-1) |
SOT109-1 |
SO-SOJ-REFLOW
SO-SOJ-WAVE WAVE_BG-BD-1 |
Not available |
All type numbers in the table below are discontinued.
| Type number | Orderable part number, (Ordering code (12NC)) | Status | Marking | Package | Package information | Reflow-/Wave soldering | Packing |
|---|---|---|---|---|---|---|---|
| HEF4521BT | HEF4521BT,652 (933406770652) |
Withdrawn / End-of-life | HEF4521BT |
SO16 (SOT109-1) |
SOT109-1 |
SO-SOJ-REFLOW
SO-SOJ-WAVE WAVE_BG-BD-1 |
SOT109-1_652 |
Environmental information
| Type number | Orderable part number | Chemical content | RoHS | RHF-indicator |
|---|---|---|---|---|
| HEF4521BT | HEF4521BT,653 | HEF4521BT |
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All type numbers in the table below are discontinued.
| Type number | Orderable part number | Chemical content | RoHS | RHF-indicator |
|---|---|---|---|---|
| HEF4521BT | HEF4521BT,652 | HEF4521BT |
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Documentation (10)
| File name | Title | Type | Date |
|---|---|---|---|
| HEF4521B | 24-stage frequency divider and oscillator | Data sheet | 2024-08-19 |
| AN11051 | Pin FMEA HEF4000 family | Application note | 2019-01-09 |
| SOT109-1 | 3D model for products with SOT109-1 package | Design support | 2020-01-22 |
| Nexperia_package_poster | Nexperia package poster | Leaflet | 2020-05-15 |
| SO16_SOT109-1_mk | plastic, small outline package; 16 leads; 1.27 mm pitch; 9.9 mm x 3.9 mm x 1.35 mm body | Marcom graphics | 2017-01-28 |
| SOT109-1 | plastic, small outline package; 16 leads; 1.27 mm pitch; 9.9 mm x 3.9 mm x 1.75 mm body | Package information | 2023-11-07 |
| HEF4521BT_Nexperia_Product_Reliability | HEF4521BT Nexperia Product Reliability | Quality document | 2024-06-16 |
| SO-SOJ-REFLOW | Footprint for reflow soldering | Reflow soldering | 2009-10-08 |
| SO-SOJ-WAVE | Footprint for wave soldering | Wave soldering | 2009-10-08 |
| WAVE_BG-BD-1 | Wave soldering profile | Wave soldering | 2021-09-08 |
Support
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Models
| File name | Title | Type | Date |
|---|---|---|---|
| SOT109-1 | 3D model for products with SOT109-1 package | Design support | 2020-01-22 |
PCB Symbol, Footprint and 3D Model
| Model Name | Description |
|---|---|
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Ordering, pricing & availability
| Type number | Orderable part number | Ordering code (12NC) | Status | Packing | Packing Quantity | Buy online |
|---|---|---|---|---|---|---|
| HEF4521BT | HEF4521BT,653 | 933406770653 | Active | Not available | 2,500 | Order product |
Sample
As a Nexperia customer you can order samples via our sales organization.
If you do not have a direct account with Nexperia our network of global and regional distributors is available and equipped to support you with Nexperia samples. Check out the list of official distributors.
How does it work?
The interactive datasheets are based on the Nexperia MOSFET precision electrothermal models. With our interactive datasheets you can simply specify your own conditions interactively. Start by changing the values of the conditions. You can do this by using the sliders in the condition fields. By dragging the sliders you will see how the MOSFET will perform at the new conditions set.
HEF4521BT
24-stage frequency divider and oscillator
Buy from Nexperia
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