Loads when you scroll to it. Unloads after 5 minutes in the background.

Symbol & Footprint

Schematic Symbol

Open full view ↗
Loads when you scroll to it. Unloads after 5 minutes in the background.

PCB Footprint

Open full view ↗
Loads when you scroll to it. Unloads after 5 minutes in the background.
Loads when you scroll to it. Unloads after 5 minutes in the background.
Download PDF
Contents

README

markdown

LMX2531LQX2570E

Texas Instruments · Clock Generators, PLLs, Frequency Synthesizers · WQFN-36(6x6)

LMX2531LQX2570E from Texas Instruments, in a WQFN-36(6x6). Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin Name Type Function
1 VccDIG power_in Power supply for the digital LDO circuitry; input may range from 2.8 to 3.2 V, with bypass capacitors placed as close as possible to this pin and ground.
2 NC unconnected No connect; do not ground.
3 GND power_in Ground.
4 NC unconnected No connect; do not ground.
5 NC unconnected No connect; do not ground.
6 VregBUF power_out Internally regulated voltage for the VCO buffer circuitry; connect to ground with a capacitor.
7 NC unconnected No connect; do not ground.
8 DATA input MICROWIRE serial data input (high-impedance CMOS) that must not exceed 2.75 V; data is clocked in MSB first and the last bits clocked in form the control or register select bits.
9 CLK input MICROWIRE clock input (high-impedance CMOS) that must not exceed 2.75 V; data is clocked into the shift register on the rising edge.
10 LE input MICROWIRE latch enable input (high-impedance CMOS) that must not exceed 2.75 V; data in the shift register is loaded into the selected latch register when LE goes high.
11 CE input Chip enable input (high-impedance CMOS) that must not exceed 2.75 V; when CE is brought high the device is powered up.
12 NC unconnected No connect; do not ground.
13 NC unconnected No connect; do not ground.
14 NC unconnected No connect; do NOT ground, and the pad above these pins should also not be grounded.
15 NC unconnected No connect; do NOT ground, and the pad above these pins should also not be grounded.
16 VccVCO power_in Power supply for the VCO regulator circuitry; input may range from 2.8 to 3.2 V, with bypass capacitors placed as close as possible to this pin and ground.
17 VregVCO power_out Internally regulated voltage for VCO circuitry, not intended to drive an external load; connect to ground with a capacitor and some series resistance.
18 VrefVCO power_out Internal reference voltage for the VCO LDO, not intended to drive an external load; connect to ground with a capacitor.
19 GND power_in Ground for the VCO circuitry.
20 GND power_in Ground for the VCO output buffer circuitry.
21 Fout output Buffered RF output for the VCO.
22 VccBUF power_in Power supply for the VCO buffer circuitry; input may range from 2.8 to 3.2 V, with bypass capacitors placed as close as possible to this pin and ground.
23 Vtune input Tuning voltage input for the VCO, connected to the CPout pin through an external passive loop filter.
24 CPout output Charge pump output for the PLL, connected to Vtune through an external passive loop filter.
25 FLout output Open-drain NMOS output used for FastLock or as a general-purpose output; a pull-up resistor is needed when the open-drain state is used.
26 VregPLL1 power_out Internally regulated voltage for the PLL charge pump, not intended to drive an external load; connect to ground with a capacitor.
27 VccPLL power_in Power supply for the PLL; input may range from 2.8 to 3.2 V, with bypass capacitors placed as close as possible to this pin and ground.
28 VregPLL2 power_out Internally regulated voltage for the RF digital circuitry, not intended to drive an external load; connect to ground with a capacitor.
29 NC unconnected No connect; do not ground.
30 Ftest/LD output Multiplexed CMOS output typically used to monitor the PLL lock condition; its output level is set by VOH and VOL, not by the supply voltage.
31 OSCin input Oscillator input.
32 OSCin* input Oscillator complementary input; when a single-ended source is used, a bypass capacitor should be placed as close as possible to this pin and connected to ground.
33 Test output Test pin for test purposes; should be grounded for normal operation.
34 GND power_in Ground.
35 NC unconnected No connect; do not ground.
36 VregDIG power_out Internally regulated voltage for the LDO digital circuitry.
37 EP passive Exposed pad (from the footprint; not named in the datasheet pin table).

Key specifications

Parameter Value
Manufacturer Texas Instruments
Package WQFN-36(6x6)
Category Clock/Timing
Pins 37

CAD (KiCad official)

  • Symbol: LMX2531LQX2570E
  • Footprint: Package_DFN_QFN:QFN-36-1EP_6x6mm_P0.5mm_EP3.7x3.7mm
  • 3D model: WQFN-36(6x6) (KiCad packages3D, STEP)
  • 3D model files: lmx2531lqx2570e-etched.step / lmx2531lqx2570e-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); lmx2531lqx2570e.step / lmx2531lqx2570e.glb are the bare package body.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Texas Instruments datasheet (47 pp, sha256 640d071469707184, retrieved 2026-10-12, tier: lcsc)
  • Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-haiku-5-5 (text), consensus claude-sonnet-5-5 (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF