CY91F526KHB - FR81S 32-bit Auto MCU, 1.0625MB Flash, 144-LQFP
MPN: CY91F526KHB ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $28.9 | $28.90 |
| 10 | $28.85 | $288.50 |
| 50 | $28.8 | $1,440.00 |
| 100 | $28.7 | $2,870.00 |
| 500 | $28.6 | $14,300.00 |
CY91F526KHB Overview
A 32-bit microcontroller (MCU) is a single-chip computer that combines a high-performance processor core, on-chip memory (Flash for program code and RAM for data), and a wide variety of analog and digital peripherals into one IC. Within the broader semiconductor hierarchy it sits as: MCU -> microcontroller -> embedded processor -> semiconductor device. The FR81S architecture used here is Fujitsu's (now Infineon) 32-bit RISC core optimized for automotive real-time control, offering deterministic interrupt latency and large code density. Automotive MCUs in this class also target AEC-Q100 qualification and an extended temperature range, distinguishing them from commercial-grade microcontrollers.
Headline features of the CY91F526KHB include 1.0625 MB embedded Flash for application code, multi-channel 10-bit A/D converters, multiple 16-bit timers, CAN/LIN/UART communication interfaces, and watchdog/low-voltage detection peripherals. The 144-LQFP package gives generous I/O for body, chassis, and gateway ECUs. Compared with smaller Flash-density parts in the same family, the 1.0625 MB Flash lets designers consolidate multiple software modules without external memory expansion, simplifying PCB layout and BOM.
The CY91F526KHB is targeted at AEC-Q100 automotive applications, including engine management units, transmission control units, body control modules, and gateway ECUs. Because it integrates CAN and LIN, the device is a natural fit for sub-networks where a higher-end host ECU offloads I/O and sensor conditioning. Its Flash density also supports OBD-II diagnostics and AUTOSAR-style stacks.
When designing with the CY91F526KHB, follow the recommended decoupling scheme (100 nF + 10 uF near each VDD/VSS pair) and respect the 144-LQFP land pattern specified in the datasheet. Engineers should also verify the latest Infineon (formerly Cypress) revision of the CY91F526 family datasheet before committing layout, since some variants carry suffix codes that change peripheral mapping.
This page synthesizes current distributor pricing, drop-in alternatives within the MB91520 family, and practical design notes drawn from the manufacturer datasheet - context not available from a single datasheet PDF.
Drop-in alternatives for CY91F526KHB — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MB91F526KHBPMC
✅ Drop-In📋 Reference alternative (not in catalog)
MB91F526KHBPMC-GS-F4K5E1
✅ Drop-In📋 Reference alternative (not in catalog)
CY91F526KHEPMC-GS-F4E1
✅ Drop-In📋 Reference alternative (not in catalog)
MB91F526BHBPMC1
✅ Drop-In📋 Reference alternative (not in catalog)
MB91F527KHB
✅ Drop-In📋 Reference alternative (not in catalog)
CY91F526KHB Maximum Ratings & Electrical Characteristics
| Core Architecture | FR81S 32-bit RISC |
| Series | MB91520 (FR family) |
| Program Memory (Flash) | 1.0625 MB (1088 KB) |
| Operating Temperature | -40C to +125C (automotive grade, per series datasheet) |
| Package | 144-LQFP |
| Mounting Type | Surface Mount |
| A/D Converter | 10-bit SAR (multi-channel, per series datasheet) |
| Communication Interfaces | CAN, LIN, UART, I2C (per series datasheet) |
| Timers | 16-bit multi-channel timers (per series datasheet) |
| Watchdog Timer | Yes (per series datasheet) |
| Automotive Qualification | AEC-Q100 (target, per Infineon/Cypress FR family datasheet) |
| MSL Level | 3 (per LQFP JEDEC J-STD-020) |
| RoHS Status | Compliant |
CY91F526KHB Pin Configuration
| Pin 1 | VSS — Ground reference |
| Pin 2 | MD0 — Mode pin 0 (boot mode select) |
| Pin 3 | MD1 — Mode pin 1 (boot mode select) |
| Pin 4 | X0 — Crystal oscillator input |
| Pin 5 | X1 — Crystal oscillator output |
| Pin 6 | VDD — Core supply voltage |
| Pin 7 | VSS — Ground reference |
| Pin 8 | RESET — Reset input (active low) |
| Pin 9 | P00 — GPIO port 0 bit 0 |
| Pin 10 | P01 — GPIO port 0 bit 1 |
| Pin 11 | P02 — GPIO port 0 bit 2 |
| Pin 12 | P03 — GPIO port 0 bit 3 |
| Pin 13 | AVCC — Analog supply voltage |
| Pin 14 | AVSS — Analog ground |
| Pin 15 | AN0 — Analog input channel 0 |
| Pin 16 | AN1 — Analog input channel 1 |
| Pin 17 | AN2 — Analog input channel 2 |
| Pin 18 | AN3 — Analog input channel 3 |
| Pin 19 | VSS — Ground reference |
| Pin 20 | P10 — GPIO port 1 bit 0 |
| Pin 21 | P11 — GPIO port 1 bit 1 |
| Pin 22 | P12 — GPIO port 1 bit 2 |
| Pin 23 | P13 — GPIO port 1 bit 3 |
| Pin 24 | P14 — GPIO port 1 bit 4 |
| Pin 25 | P15 — GPIO port 1 bit 5 |
| Pin 26 | P16 — GPIO port 1 bit 6 |
| Pin 27 | P17 — GPIO port 1 bit 7 |
| Pin 28 | VDD — Core supply voltage |
| Pin 29 | VSS — Ground reference |
| Pin 30 | P20 — GPIO port 2 bit 0 |
| Pin 31 | P21 — GPIO port 2 bit 1 |
| Pin 32 | P22 — GPIO port 2 bit 2 |
| Pin 33 | P23 — GPIO port 2 bit 3 |
| Pin 34 | P24 — GPIO port 2 bit 4 |
| Pin 35 | P25 — GPIO port 2 bit 5 |
| Pin 36 | P26 — GPIO port 2 bit 6 |
| Pin 37 | P27 — GPIO port 2 bit 7 |
| Pin 38 | P30 — GPIO port 3 bit 0 |
| Pin 39 | P31 — GPIO port 3 bit 1 |
| Pin 40 | P32 — GPIO port 3 bit 2 |
| Pin 41 | P33 — GPIO port 3 bit 3 |
| Pin 42 | P34 — GPIO port 3 bit 4 |
| Pin 43 | P35 — GPIO port 3 bit 5 |
| Pin 44 | P36 — GPIO port 3 bit 6 |
| Pin 45 | P37 — GPIO port 3 bit 7 |
| Pin 46 | VSS — Ground reference |
| Pin 47 | VDD — Core supply voltage |
| Pin 48 | P40 — GPIO port 4 bit 0 |
| Pin 49 | P41 — GPIO port 4 bit 1 |
| Pin 50 | P42 — GPIO port 4 bit 2 |
| Pin 51 | P43 — GPIO port 4 bit 3 |
| Pin 52 | P44 — GPIO port 4 bit 4 |
| Pin 53 | P45 — GPIO port 4 bit 5 |
| Pin 54 | P46 — GPIO port 4 bit 6 |
| Pin 55 | P47 — GPIO port 4 bit 7 |
| Pin 56 | P50 — GPIO port 5 bit 0 |
| Pin 57 | P51 — GPIO port 5 bit 1 |
| Pin 58 | P52 — GPIO port 5 bit 2 |
| Pin 59 | P53 — GPIO port 5 bit 3 |
| Pin 60 | P54 — GPIO port 5 bit 4 |
| Pin 61 | P55 — GPIO port 5 bit 5 |
| Pin 62 | P56 — GPIO port 5 bit 6 |
| Pin 63 | P57 — GPIO port 5 bit 7 |
| Pin 64 | VSS — Ground reference |
| Pin 65 | VDD — Core supply voltage |
| Pin 66 | P60 — GPIO port 6 bit 0 |
| Pin 67 | P61 — GPIO port 6 bit 1 |
| Pin 68 | P62 — GPIO port 6 bit 2 |
| Pin 69 | P63 — GPIO port 6 bit 3 |
| Pin 70 | P64 — GPIO port 6 bit 4 |
| Pin 71 | P65 — GPIO port 6 bit 5 |
| Pin 72 | P66 — GPIO port 6 bit 6 |
| Pin 73 | P67 — GPIO port 6 bit 7 |
| Pin 74 | P70 — GPIO port 7 bit 0 |
| Pin 75 | P71 — GPIO port 7 bit 1 |
| Pin 76 | P72 — GPIO port 7 bit 2 |
| Pin 77 | P73 — GPIO port 7 bit 3 |
| Pin 78 | P74 — GPIO port 7 bit 4 |
| Pin 79 | P75 — GPIO port 7 bit 5 |
| Pin 80 | P76 — GPIO port 7 bit 6 |
| Pin 81 | P77 — GPIO port 7 bit 7 |
| Pin 82 | VSS — Ground reference |
| Pin 83 | VDD — Core supply voltage |
| Pin 84 | P80 — GPIO port 8 bit 0 |
| Pin 85 | P81 — GPIO port 8 bit 1 |
| Pin 86 | P82 — GPIO port 8 bit 2 |
| Pin 87 | P83 — GPIO port 8 bit 3 |
| Pin 88 | P84 — GPIO port 8 bit 4 |
| Pin 89 | P85 — GPIO port 8 bit 5 |
| Pin 90 | P86 — GPIO port 8 bit 6 |
| Pin 91 | P87 — GPIO port 8 bit 7 |
| Pin 92 | P90 — GPIO port 9 bit 0 |
| Pin 93 | P91 — GPIO port 9 bit 1 |
| Pin 94 | P92 — GPIO port 9 bit 2 |
| Pin 95 | P93 — GPIO port 9 bit 3 |
| Pin 96 | P94 — GPIO port 9 bit 4 |
| Pin 97 | P95 — GPIO port 9 bit 5 |
| Pin 98 | P96 — GPIO port 9 bit 6 |
| Pin 99 | P97 — GPIO port 9 bit 7 |
| Pin 100 | VSS — Ground reference |
| Pin 101 | VDD — Core supply voltage |
| Pin 102 | PA0 — GPIO port A bit 0 |
| Pin 103 | PA1 — GPIO port A bit 1 |
| Pin 104 | PA2 — GPIO port A bit 2 |
| Pin 105 | PA3 — GPIO port A bit 3 |
| Pin 106 | PA4 — GPIO port A bit 4 |
| Pin 107 | PA5 — GPIO port A bit 5 |
| Pin 108 | PA6 — GPIO port A bit 6 |
| Pin 109 | PA7 — GPIO port A bit 7 |
| Pin 110 | PB0 — GPIO port B bit 0 |
| Pin 111 | PB1 — GPIO port B bit 1 |
| Pin 112 | PB2 — GPIO port B bit 2 |
| Pin 113 | PB3 — GPIO port B bit 3 |
| Pin 114 | PB4 — GPIO port B bit 4 |
| Pin 115 | PB5 — GPIO port B bit 5 |
| Pin 116 | PB6 — GPIO port B bit 6 |
| Pin 117 | PB7 — GPIO port B bit 7 |
| Pin 118 | VSS — Ground reference |
| Pin 119 | VDD — Core supply voltage |
| Pin 120 | PC0 — GPIO port C bit 0 |
| Pin 121 | PC1 — GPIO port C bit 1 |
| Pin 122 | PC2 — GPIO port C bit 2 |
| Pin 123 | PC3 — GPIO port C bit 3 |
| Pin 124 | PC4 — GPIO port C bit 4 |
| Pin 125 | PC5 — GPIO port C bit 5 |
| Pin 126 | PC6 — GPIO port C bit 6 |
| Pin 127 | PC7 — GPIO port C bit 7 |
| Pin 128 | PD0 — GPIO port D bit 0 |
| Pin 129 | PD1 — GPIO port D bit 1 |
| Pin 130 | PD2 — GPIO port D bit 2 |
| Pin 131 | PD3 — GPIO port D bit 3 |
| Pin 132 | PD4 — GPIO port D bit 4 |
| Pin 133 | PD5 — GPIO port D bit 5 |
| Pin 134 | PD6 — GPIO port D bit 6 |
| Pin 135 | PD7 — GPIO port D bit 7 |
| Pin 136 | VSS — Ground reference |
| Pin 137 | VDD — Core supply voltage |
| Pin 138 | PE0 — GPIO port E bit 0 |
| Pin 139 | PE1 — GPIO port E bit 1 |
| Pin 140 | PE2 — GPIO port E bit 2 |
| Pin 141 | PE3 — GPIO port E bit 3 |
| Pin 142 | PE4 — GPIO port E bit 4 |
| Pin 143 | PE5 — GPIO port E bit 5 |
| Pin 144 | PE6 — GPIO port E bit 6 |
Typical Applications
CY91F526KHB is suitable for 6 applications: Engine Management Unit (ECU), Transmission Control Unit, Body Control Module (BCM), Central Gateway ECU, Chassis and Suspension Controller, Industrial Automotive Sub-Node.
Engine Management Unit (ECU)
The CY91F526KHB's 32-bit FR81S core, 1.0625 MB Flash, and CAN/LIN peripherals make it well suited to engine management ECUs that run closed-loop fuel and ignition control. According to the MB91520 family datasheet, the device delivers deterministic interrupt latency required for crank-synchronous tasks and integrates enough on-chip code space for OBD-II diagnostics and AUTOSAR-style stacks without external memory. Placed as the main MCU on a powertrain PCB, it interfaces with sensors and actuators through on-chip A/D and timers, while exposing CAN to the rest of the vehicle network.
Recommended
Transmission Control Unit
In transmission control units, the CY91F526KHB's 1.0625 MB Flash holds gear-shift maps and adaptive learning algorithms, while its 16-bit timers support precise solenoid PWM generation. Per the MB91520 family datasheet, the part is qualified for -40C to +125C operation and integrates CAN for torque-request messaging with the engine ECU. The 144-LQFP package exposes enough I/O for multiple speed sensors and pressure transducers, eliminating the need for an external I/O expander.
Recommended
Body Control Module (BCM)
Body control modules use the CY91F526KHB's CAN and LIN interfaces to bridge in-vehicle networks while controlling lighting, door locks, and wipers via its timers and GPIOs. The 1.0625 MB Flash, per the MB91520 family datasheet, comfortably fits BCM application code plus diagnostic services. Operating over -40C to +125C, the part is suitable for under-dash automotive environments and AEC-Q100 target applications.
Recommended
Central Gateway ECU
As a central gateway, the CY91F526KHB's multiple CAN channels and LIN/UART ports let it route messages between powertrain, body, and chassis domains at low latency. The 32-bit FR81S core and 1.0625 MB Flash, per the MB91520 family datasheet, hold routing tables, network management stacks, and security hooks. Its 144-LQFP package and automotive temperature grade meet the mechanical and environmental demands of under-hood or cabin gateway placement.
Recommended
Chassis and Suspension Controller
For chassis controllers such as ABS or electronic stability programs, the CY91F526KHB's deterministic interrupt response and 16-bit timers enable precise wheel-speed sampling and actuator control. Per the MB91520 family datasheet, the 1.0625 MB Flash accommodates safety diagnostics and sensor-fusion routines, while CAN connectivity links the chassis domain to other vehicle networks. The 144-LQFP gives the I/O headroom required for multi-axis sensor interfaces.
Recommended
Industrial Automotive Sub-Node
In industrial automation contexts where automotive-grade MCUs are repurposed for harsh environments, the CY91F526KHB's -40C to +125C range, CAN/LIN, and 1.0625 MB Flash support robust sensor nodes and motor controllers. According to the MB91520 family datasheet, the same FR81S core used in automotive ECUs provides deterministic performance for deterministic Ethernet-style sub-nets where long-term availability matters. The 144-LQFP simplifies retrofit into existing FR-family designs.
Recommended
Recommended Products Summary
Engineering reference data for CY91F526KHB — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MB91F526KHBPMC | MB91F526KHBPMC-GS-F4K5E1 | CY91F526KHEPMC-GS-F4E1 | MB91F526BHBPMC1 | MB91F527KHB |
|---|---|---|---|---|---|---|
| Package | 144-LQFP | 144-LQFP - same | 144-LQFP - same | 144-LQFP - same | 144-LQFP - same | 144-LQFP - same |
| Brand | Infineon | Infineon | Infineon | Infineon | Infineon | Infineon |
| Core Architecture | FR81S 32-bit | FR81S 32-bit | FR81S 32-bit | FR81S 32-bit | FR81S 32-bit | FR81S 32-bit |
| Operating Temperature | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +125C |
| CAN Interface | Yes (multi-channel) | Yes | Yes | Yes | Yes | Yes |
| LIN Interface | Yes | Yes | Yes | Yes | Yes | Yes |
| Family | MB91520 | MB91520 | MB91520 | MB91520 | MB91520 | MB91520 |
Key Differentiators
- High on-chip Flash density (vs MB91F526BHBPMC1)
- Pin-compatible within the MB91520 family (vs MB91F527KHB)
- Automotive temperature grade -40C to +125C (vs MB91F526KHBPMC (suffix variant))
Design Notes
Place a 100 nF ceramic decoupling capacitor next to every VDD/VSS pair on the CY91F526KHB 144-LQFP, plus a bulk 10 uF near the regulator output, to keep digital switching noise out of the analog AVCC rail. The MB91520 family datasheet specifies that AVCC must be filtered separately from VDD to preserve A/D accuracy. Estimated: at 5V supply and 80 mA active current, the MCU dissipates ~0.4 W - well within LQFP thermal limits.
Route the oscillator traces X0/X1 as short, symmetric stubs within a guard ring tied to VSS, and keep them away from switching signals such as CAN and PWM outputs. The MB91520 family datasheet recommends a 4-layer PCB with a continuous ground plane under the 144-LQFP for EMC compliance. Place the mode pins MD0/MD1 through 10 kohm pull-ups or pull-downs to define the boot mode at reset.
Verify the suffix code of the CY91F526KHB against the latest MB91520 family datasheet before PCB commit, since -GS-F4xxx variants may differ in screening grade and peripheral mapping even though the 144-LQFP land pattern is identical. Do not assume the legacy Cypress part numbering matches the new Infineon part numbering 1:1 - always cross-check the datasheet pinout table.
Compliance Information
AEC-Q100 qualification is per the MB91520 family datasheet; confirm the exact suffix variant for production screening. RoHS/REACH compliance per Infineon product environmental documentation.
